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Kumar A, Chakravorty S, Yang T, Russo TA, Newton SM, Klebba PE. Siderophore-mediated iron acquisition by Klebsiella pneumoniae. J Bacteriol 2024; 206:e0002424. [PMID: 38591913 PMCID: PMC11112993 DOI: 10.1128/jb.00024-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/05/2024] [Indexed: 04/10/2024] Open
Abstract
Microbes synthesize and secrete siderophores, that bind and solubilize precipitated or otherwise unavailable iron in their microenvironments. Gram (-) bacterial TonB-dependent outer membrane receptors capture the resulting ferric siderophores to begin the uptake process. From their similarity to fepA, the structural gene for the Escherichia coli ferric enterobactin (FeEnt) receptor, we identified four homologous genes in the human and animal ESKAPE pathogen Klebsiella pneumoniae (strain Kp52.145). One locus encodes IroN (locus 0027 on plasmid pII), and three other loci encode other FepA orthologs/paralogs (chromosomal loci 1658, 2380, and 4984). Based on the crystal structure of E. coli FepA (1FEP), we modeled the tertiary structures of the K. pneumoniae FepA homologs and genetically engineered individual Cys substitutions in their predicted surface loops. We subjected bacteria expressing the Cys mutant proteins to modification with extrinsic fluorescein maleimide (FM) and used the resulting fluorescently labeled cells to spectroscopically monitor the binding and transport of catecholate ferric siderophores by the four different receptors. The FM-modified FepA homologs were nanosensors that defined the ferric catecholate uptake pathways in pathogenic strains of K. pneumoniae. In Kp52.145, loci 1658 and 4984 encoded receptors that primarily recognized and transported FeEnt; locus 0027 produced a receptor that principally bound and transported FeEnt and glucosylated FeEnt (FeGEnt); locus 2380 encoded a protein that bound ferric catecholate compounds but did not detectably transport them. The sensors also characterized the uptake of iron complexes, including FeGEnt, by the hypervirulent, hypermucoviscous K. pneumoniae strain hvKp1. IMPORTANCE Both commensal and pathogenic bacteria produce small organic chelators, called siderophores, that avidly bind iron and increase its bioavailability. Klebsiella pneumoniae variably produces four siderophores that antagonize host iron sequestration: enterobactin, glucosylated enterobactin (also termed salmochelin), aerobactin, and yersiniabactin, which promote colonization of different host tissues. Abundant evidence links bacterial iron acquisition to virulence and infectious diseases. The data we report explain the recognition and transport of ferric catecholates and other siderophores, which are crucial to iron acquisition by K. pneumoniae.
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Affiliation(s)
- Ashish Kumar
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
- Department of Rare Blood and Musculoskeletal Disorders, Sanofi, Cambridge, Massachusetts, USA
| | - Somnath Chakravorty
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
- Jacobs School of Medicine, University at Buffalo, Buffalo, New York, USA
| | - Taihao Yang
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Thomas A. Russo
- Jacobs School of Medicine, University at Buffalo, Buffalo, New York, USA
- Veterans Administration, Western New York Healthcare System, Buffalo, New York, USA
| | - Salete M. Newton
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Phillip E. Klebba
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
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2
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Hou G, Ahmad S, Li Y, Yan D, Yang S, Chen S, Qiu Z, Yu X, Li N, Li Y, Liang Y, Leng Q, Qu Y. Epidemiological, Virulence, and Antibiotic Resistance Analysis of Klebsiella pneumoniae, a Major Source of Threat to Livestock and Poultry in Some Regions of Xinjiang, China. Animals (Basel) 2024; 14:1433. [PMID: 38791650 PMCID: PMC11117231 DOI: 10.3390/ani14101433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 05/03/2024] [Accepted: 05/07/2024] [Indexed: 05/26/2024] Open
Abstract
Klebsiella pneumoniae (K. pneumoniae) is recognized as a zoonotic pathogen with an increasing threat to livestock and poultry. However, research on K. pneumoniae of animal origin remains limited. To address the gap, a comprehensive investigation was carried out by collecting a total of 311 samples from the farms of four animal species (dairy cow, chicken, sheep, and pig) in selected areas of Xinjiang, China. Isolates were identified by khe gene amplification and 16S rRNA gene sequencing. Genotyping of K. pneumonia isolates was performed using wzi typing and multilocus sequence typing (MLST). PCR was employed to identify virulence and resistance genes. An antibiotic susceptibility test was conducted using the Kirby-Bauer method. The findings revealed an isolation of 62 K. pneumoniae strains, with an average isolation rate of 19.94%, with the highest proportion originating from cattle sources (33.33%). Over 85.00% of these isolates harbored six virulence genes (wabG, uge, fimH, markD, entB, and ureA); while more than 75.00% of isolates possessed four resistance genes (blaTEM, blaSHV, oqxA, and gyrA). All isolates exhibited complete resistance to ampicillin and demonstrated substantial resistance to sulfisoxazole, amoxicillin/clavulanic acid, and enrofloxacin, with an antibiotic resistance rate of more than 50%. Furthermore, 48.39% (30/62) of isolates were classified as multidrug-resistant (MDR) strains, with a significantly higher isolation rate observed in the swine farms (66.67%) compared to other farms. Genetic characterization revealed the classification of the 62 isolates into 30 distinct wzi allele types or 35 different sequence types (STs). Notably, we identified K. pneumoniae strains of dairy and swine origin belonging to the same ST42 and wzi33-KL64 types, as well as strains of dairy and chicken origin belonging to the same wzi31-KL31-K31 type. These findings emphasize the widespread occurrence of drug-resistant K. pneumoniae across diverse animal sources in Xinjiang, underscoring the high prevalence of multidrug resistance. Additionally, our results suggest the potential for animal-to-animal transmission of K. pneumoniae and there was a correlation between virulence genes and antibiotic resistance genes. Moreover, the current study provides valuable data on the prevalence, antibiotic resistance, and genetic diversity of K. pneumoniae originating from diverse animal sources in Xinjiang, China.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Qingwen Leng
- College of Animal Science and Technology, Shihezi University, Shihezi 832003, China; (G.H.); (S.A.); (Y.L.); (D.Y.); (S.Y.); (S.C.); (Z.Q.); (X.Y.); (N.L.); (Y.L.); (Y.L.)
| | - Yonggang Qu
- College of Animal Science and Technology, Shihezi University, Shihezi 832003, China; (G.H.); (S.A.); (Y.L.); (D.Y.); (S.Y.); (S.C.); (Z.Q.); (X.Y.); (N.L.); (Y.L.); (Y.L.)
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3
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Kochan TJ, Nozick SH, Valdes A, Mitra SD, Cheung BH, Lebrun-Corbin M, Medernach RL, Vessely MB, Mills JO, Axline CMR, Nelson JA, VanGosen EM, Ward TJ, Ozer EA, van Duin D, Chen L, Kreiswirth BN, Long SW, Musser JM, Bulman ZP, Wunderink RG, Hauser AR. Klebsiella pneumoniae clinical isolates with features of both multidrug-resistance and hypervirulence have unexpectedly low virulence. Nat Commun 2023; 14:7962. [PMID: 38042959 PMCID: PMC10693551 DOI: 10.1038/s41467-023-43802-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 11/21/2023] [Indexed: 12/04/2023] Open
Abstract
Klebsiella pneumoniae has been classified into two types, classical K. pneumoniae (cKP) and hypervirulent K. pneumoniae (hvKP). cKP isolates are highly diverse and important causes of nosocomial infections; they include globally disseminated antibiotic-resistant clones. hvKP isolates are sensitive to most antibiotics but are highly virulent, causing community-acquired infections in healthy individuals. The virulence phenotype of hvKP is associated with pathogenicity loci responsible for siderophore and hypermucoid capsule production. Recently, convergent strains of K. pneumoniae, which possess features of both cKP and hvKP, have emerged and are cause of much concern. Here, we screen the genomes of 2,608 multidrug-resistant K. pneumoniae isolates from the United States and identify 47 convergent isolates. We perform phenotypic and genomic characterization of 12 representative isolates. These 12 convergent isolates contain a variety of antimicrobial resistance plasmids and virulence plasmids. Most convergent isolates contain aerobactin biosynthesis genes and produce more siderophores than cKP isolates but not more capsule. Unexpectedly, only 1 of the 12 tested convergent isolates has a level of virulence consistent with hvKP isolates in a murine pneumonia model. These findings suggest that additional studies should be performed to clarify whether convergent strains are indeed more virulent than cKP in mouse and human infections.
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Affiliation(s)
- Travis J Kochan
- Laboratory of Respiratory and Special Pathogens, Division of Bacterial, Parasitic, and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, USA.
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
| | - Sophia H Nozick
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Aliki Valdes
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Sumitra D Mitra
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Bettina H Cheung
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Marine Lebrun-Corbin
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Rachel L Medernach
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Madeleine B Vessely
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Jori O Mills
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Christopher M R Axline
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Julia A Nelson
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Ethan M VanGosen
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Timothy J Ward
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Egon A Ozer
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - David van Duin
- Division of Infectious Diseases, University of North Carolina, Chapel Hill, NC, USA
| | - Liang Chen
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, USA
| | - Barry N Kreiswirth
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, USA
| | - S Wesley Long
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital Research Institute, Houston, TX, USA
| | - James M Musser
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital Research Institute, Houston, TX, USA
| | - Zackery P Bulman
- College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Richard G Wunderink
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Simpson Querrey Institute for Epigenetics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Alan R Hauser
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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4
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Maciejewska B, Squeglia F, Latka A, Privitera M, Olejniczak S, Switala P, Ruggiero A, Marasco D, Kramarska E, Drulis-Kawa Z, Berisio R. Klebsiella phage KP34gp57 capsular depolymerase structure and function: from a serendipitous finding to the design of active mini-enzymes against K. pneumoniae. mBio 2023; 14:e0132923. [PMID: 37707438 PMCID: PMC10653864 DOI: 10.1128/mbio.01329-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 07/19/2023] [Indexed: 09/15/2023] Open
Abstract
IMPORTANCE In this work, we determined the structure of Klebsiella phage KP34p57 capsular depolymerase and dissected the role of individual domains in trimerization and functional activity. The crystal structure serendipitously revealed that the enzyme can exist in a monomeric state once deprived of its C-terminal domain. Based on the crystal structure and site-directed mutagenesis, we localized the key catalytic residues in an intra-subunit deep groove. Consistently, we show that C-terminally trimmed KP34p57 variants are monomeric, stable, and fully active. The elaboration of monomeric, fully active phage depolymerases is innovative in the field, as no previous example exists. Indeed, mini phage depolymerases can be combined in chimeric enzymes to extend their activity ranges, allowing their use against multiple serotypes.
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Affiliation(s)
- Barbara Maciejewska
- Department of Pathogen Biology and Immunology, University of Wrocław, Wrocław, Poland
| | - Flavia Squeglia
- Institute of Biostructures and Bioimaging, CNR, Napoli, Italy
| | - Agnieszka Latka
- Department of Pathogen Biology and Immunology, University of Wrocław, Wrocław, Poland
| | - Mario Privitera
- Institute of Biostructures and Bioimaging, CNR, Napoli, Italy
| | - Sebastian Olejniczak
- Department of Pathogen Biology and Immunology, University of Wrocław, Wrocław, Poland
| | - Paulina Switala
- Department of Pathogen Biology and Immunology, University of Wrocław, Wrocław, Poland
| | | | - Daniela Marasco
- Department of Pharmacy, University of Naples Federico II, Napoli, Italy
| | - Eliza Kramarska
- Institute of Biostructures and Bioimaging, CNR, Napoli, Italy
| | - Zuzanna Drulis-Kawa
- Department of Pathogen Biology and Immunology, University of Wrocław, Wrocław, Poland
| | - Rita Berisio
- Institute of Biostructures and Bioimaging, CNR, Napoli, Italy
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5
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Sultana T, Duffin RN, Blair VL, Andrews PC. Gallium reactivates first and second generation quinolone antibiotics towards drug-resistant Klebsiella pneumoniae. Chem Commun (Camb) 2023; 59:11093-11096. [PMID: 37642496 DOI: 10.1039/d3cc02916f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Herein, we report on a series of homoleptic [GaL3] and heteroleptic organometallic [GaMe2L] complexes of inactive quinolone antibiotics; nalidixic acid, oxolinic acid and norfloxacin with their antibacterial activity (MIC 0.024-0.781 μM) towards four multi-drug resistant strains of Klebsiella pneumoniae through complexation to gallium.
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Affiliation(s)
- Tania Sultana
- School of Chemistry, Monash University, Clayton, Melbourne, VIC 3800, Australia.
| | - Rebekah N Duffin
- School of Chemistry, Monash University, Clayton, Melbourne, VIC 3800, Australia.
| | - Victoria L Blair
- School of Chemistry, Monash University, Clayton, Melbourne, VIC 3800, Australia.
| | - Philip C Andrews
- School of Chemistry, Monash University, Clayton, Melbourne, VIC 3800, Australia.
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6
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Chu WHW, Tan YH, Tan SY, Chen Y, Yong M, Lye DC, Kalimuddin S, Archuleta S, Gan YH. Acquisition of regulator on virulence plasmid of hypervirulent Klebsiella allows bacterial lifestyle switch in response to iron. mBio 2023; 14:e0129723. [PMID: 37530523 PMCID: PMC10470599 DOI: 10.1128/mbio.01297-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 06/08/2023] [Indexed: 08/03/2023] Open
Abstract
Hypervirulent Klebsiella pneumoniae causes liver abscess and potentially devastating metastatic complications. The majority of Klebsiella-induced liver abscess are caused by the CG23-I sublineage of hypervirulent Klebsiella pneumoniae. This and some other lineages possess a >200-kb virulence plasmid. We discovered a novel protein IroP nestled in the virulence plasmid-encoded salmochelin operon that cross-regulates and suppresses the promoter activity of chromosomal type 3 fimbriae (T3F) gene transcription. IroP is itself repressed by iron through the ferric uptake regulator. Iron-rich conditions increase T3F and suppress capsule mucoviscosity, leading to biofilm formation and cell adhesion. Conversely, iron-poor conditions cause a transcriptional switch to hypermucoid capsule production and T3F repression. The likely acquisition of iroP on mobile genetic elements and successful adaptive integration into the genetic circuitry of a major lineage of hypervirulent K. pneumoniae reveal a powerful example of plasmid chromosomal cross talk that confers an evolutionary advantage. Our discovery also addresses the conundrum of how the hypermucoid capsule that impedes adhesion could be regulated to facilitate biofilm formation and colonization. The acquired ability of the bacteria to alternate between a state favoring dissemination and one that favors colonization in response to iron availability through transcriptional regulation offers novel insights into the evolutionary success of this pathogen. IMPORTANCE Hypervirulent Klebsiella pneumoniae contributes to the majority of monomicrobial-induced liver abscess infections that can lead to several other metastatic complications. The large virulence plasmid is highly stable in major lineages, suggesting that it provides survival benefits. We discovered a protein IroP encoded on the virulence plasmid that suppresses expression of the type 3 fimbriae. IroP itself is regulated by iron, and we showed that iron regulates hypermucoid capsule production while inversely regulating type 3 fimbriae expression through IroP. The acquisition and integration of this inverse transcriptional switch between fimbriae and capsule mucoviscosity shows an evolved sophisticated plasmid-chromosomal cross talk that changes the behavior of hypervirulent K. pneumoniae in response to a key nutrient that could contribute to the evolutionary success of this pathogen.
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Affiliation(s)
- Wilson H. W. Chu
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Yi Han Tan
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Si Yin Tan
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Yahua Chen
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Melvin Yong
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - David C. Lye
- National Centre for Infectious Diseases, Singapore, Singapore
- Tan Tock Seng Hospital, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Shirin Kalimuddin
- Department of Infectious Diseases, Singapore General Hospital, Singapore, Singapore
- Program in Emerging Infectious Disease, Duke-NUS Medical School, Singapore, Singapore
| | - Sophia Archuleta
- Division of Infectious Diseases, Department of Medicine, National University Hospital, National University Health System, Singapore, Singapore
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Yunn-Hwen Gan
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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7
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Cui F, Fan R, Wang D, Li J, Li T. Research progress on iron uptake pathways and mechanisms of foodborne microorganisms and their application in the food sector. Crit Rev Food Sci Nutr 2023:1-19. [PMID: 37099732 DOI: 10.1080/10408398.2023.2204491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Iron is one of the essential nutrients for almost all microorganisms. Under iron-limited conditions, bacteria can secrete siderophores to the outside world to absorb iron for survival. This process requires the coordinated action of energy-transducing proteins, transporters, and receptors. The spoilage factors of some spoilage bacteria and the pathogenic mechanism of pathogenic bacteria are also closely related to siderophores. Meanwhile, some siderophores have also gradually evolved toward beneficial aspects. First, a variety of siderophores are classified into three aspects. In addition, representative iron uptake systems of Gram-negative and Gram-positive bacteria are described in detail to understand the common and specific pathways of iron uptake by various bacteria. In particular, the causes of siderophore-induced bacterial pathogenicity and the methods and mechanisms of inhibiting bacterial iron absorption under the involvement of siderophores are presented. Then, the application of siderophores in the food sector is mainly discussed, such as improving the food quality of dairy products and meat, inhibiting the attack of pathogenic bacteria on food, improving the plant growth environment, and promoting plant growth. Finally, this review highlights the unresolved fate of siderophores in the iron uptake system and emphasizes further development of siderophore-based substitutes for traditional drugs, new antibiotic-resistance drugs, and vaccines in the food and health sectors.
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Affiliation(s)
- Fangchao Cui
- College of Food Science and Technology, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Rongsen Fan
- College of Food Science and Technology, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Dangfeng Wang
- College of Food Science and Technology, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
- College of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Jianrong Li
- College of Food Science and Technology, Bohai University, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Tingting Li
- Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, Dalian, China
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8
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Kot B, Piechota M, Szweda P, Mitrus J, Wicha J, Grużewska A, Witeska M. Virulence analysis and antibiotic resistance of Klebsiella pneumoniae isolates from hospitalised patients in Poland. Sci Rep 2023; 13:4448. [PMID: 36932105 PMCID: PMC10023695 DOI: 10.1038/s41598-023-31086-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 03/06/2023] [Indexed: 03/19/2023] Open
Abstract
Klebsiella pneumoniae (KP) is a nosocomial pathogen causing difficult-to-treat infections. The presence of virulence genes and antibiotic resistance of 109 KP isolates from hospitalized patients were investigated. Among them, 68.8% were multi-drug resistant (MDR) and 59.6% produced extended-spectrum beta-lactamases (ESBLs). Metallo-β-lactamases (MBLs) were produced by 22% of isolates (mainly from anus), including 16.5% of isolates producing New Delhi metallo-β-lactamase (NDM-1). The genes encoding adhesins (fimH-91.7%, mrkD-96.3%), enterobactin (entB-100%) and yersiniabactin (irp-1-88%) were frequently identified. The genes encoding salmochelin (iroD-9.2%, iroN-7.3%) and colibactin (clbA, clbB-0.9%) were identified rarely. Iron acquisition system-related kfu gene and wcaG gene involved in capsule production were identified in 6.4% and 11% of isolates, respectively. The rmpA gene associated with hypermucoviscosity was present in 6.4% of isolates. In 19.2% of isolates magA gene was detected, specific for K1 capsule serotype, while 22.9% of isolates showed K2 capsule serotype. The rmpA, iroD or iroN genes being diagnostic biomarkers for hypervirulent KP (hvKP) were detected in 16.5% of isolates. We found that 55.5% of hvKP were MDR and produced ESBLs, thus hospital KP isolates pose a serious threat to the healthcare system.
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Affiliation(s)
- Barbara Kot
- Institute of Biological Sciences, Faculty of Exact and Natural Sciences, Siedlce University of Natural Sciences and Humanities, 14 Bolesława Prusa Str., 08-110, Siedlce, Poland.
| | - Małgorzata Piechota
- Institute of Biological Sciences, Faculty of Exact and Natural Sciences, Siedlce University of Natural Sciences and Humanities, 14 Bolesława Prusa Str., 08-110, Siedlce, Poland
| | - Piotr Szweda
- Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdańsk University of Technology, 11/12 G. Narutowicza Str., 80-233, Gdańsk, Poland
| | - Joanna Mitrus
- Institute of Biological Sciences, Faculty of Exact and Natural Sciences, Siedlce University of Natural Sciences and Humanities, 14 Bolesława Prusa Str., 08-110, Siedlce, Poland
| | - Jolanta Wicha
- Medical Microbiological Laboratory, Our Lady of Perpetual Help Hospital, 1/3 Gdyńska Str., 05-200, Wołomin, Poland
| | - Agata Grużewska
- Institute of Agriculture and Horticulture, Faculty of Agrobioengineering and Animal Husbandry, Siedlce University of Natural Sciences and Humanities, 12 Bolesława Prusa Str., 08-110, Siedlce, Poland
| | - Małgorzata Witeska
- Department of Ichthyology and Biotechnology in Aquaculture, Institute of Animal Science, Warsaw University of Life Sciences, Ciszewskiego 8, 02-786, Warsaw, Poland
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9
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Namikawa H, Oinuma KI, Yamada K, Kaneko Y, Kakeya H, Shuto T. Predictors of hypervirulent Klebsiella pneumoniae infections: a systematic review and meta-analysis. J Hosp Infect 2023; 134:153-160. [PMID: 36813165 DOI: 10.1016/j.jhin.2023.02.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 01/26/2023] [Accepted: 02/08/2023] [Indexed: 02/24/2023]
Abstract
BACKGROUND Hypervirulent Klebsiella pneumoniae (hvKp) infections confer notable morbidity and mortality. Differential diagnosis to determine whether the infections are caused by either the hvKp or classical K. pneumoniae (cKp) strain is particularly important for undertaking optimal clinical care and infection control efforts. AIM To identify and assess the potential predictors of hvKp infections. METHODS PubMed, Web of Science, and Cochrane Library databases were searched for all relevant publications from January 2000 to March 2022. The search terms included a combination of the following terms: (i) Klebsiella pneumoniae or K. pneumoniae and (ii) hypervirulent or hypervirulence. A meta-analysis of factors for which risk ratio was reported in three or more studies was conducted, and at least one statistically significant association was identified. FINDINGS In this systematic review of 11 observational studies, a total of 1392 patients with K. pneumoniae infection and 596 (42.8%) with hvKp strains were evaluated. In the meta-analysis, diabetes mellitus and liver abscess (pooled risk ratio: 2.61 (95% confidence interval: 1.79-3.80) and 9.04 (2.58-31.72), respectively; all P < 0.001) were predictors of hvKp infections. CONCLUSION For patients with a history of the abovementioned predictors, prudent management, including the search for multiple sites of infection and/or metastatic spread and the enforcement of an early and appropriate source control procedure, should be initiated in consideration of the potential presence of hvKp. We believe that this research highlights the urgent need for increasing clinical awareness of the management of hvKp infections.
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Affiliation(s)
- H Namikawa
- Department of Medical Education and General Practice, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan.
| | - K-I Oinuma
- Department of Bacteriology, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan; Research Center for Infectious Disease Sciences, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
| | - K Yamada
- Research Center for Infectious Disease Sciences, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan; Department of Infection Control Science, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
| | - Y Kaneko
- Department of Bacteriology, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan; Research Center for Infectious Disease Sciences, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
| | - H Kakeya
- Research Center for Infectious Disease Sciences, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan; Department of Infection Control Science, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
| | - T Shuto
- Department of Medical Education and General Practice, Osaka Metropolitan University, Graduate School of Medicine, Osaka, Japan
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10
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Presence of Polyketide Synthase (PKS) Gene and Counterpart Virulence Determinants in Klebsiella pneumoniae Strains Enhances Colorectal Cancer Progression In-Vitro. Microorganisms 2023; 11:microorganisms11020443. [PMID: 36838407 PMCID: PMC9965769 DOI: 10.3390/microorganisms11020443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/07/2023] [Accepted: 01/08/2023] [Indexed: 02/12/2023] Open
Abstract
Klebsiella pneumoniae (K. pneumoniae) colonizes the human gut and is a causative factor of pyogenic liver abscess (PLA). Retrospective studies conducted on K. pneumoniae PLA patients revealed subsequent CRC development in later years of their life with increasing prevalence of these strains harbouring polyketide synthase (PKS) genes. To our knowledge there are no known studies directly implicating K. pneumoniae with CRC to date. Our aims are to characterize K. pneumoniae isolates from CRC patients and investigate its effects on cell proliferation in vitro. K. pneumoniae isolates were characterized by screening virulence genes including polyketide synthase (PKS), biofilm assay, antibiotic susceptibility, and string test to determine hypervirulent (hvKp) strains. Solubilised antigens of selected K. pneumoniae isolates were co-cultured with primary colon cell lines and CRC cell lines (Stage I-IV) for 48 h. The enhancement of proliferation was measured through MTT and ECIS assay. Twenty-five percent of K. pneumoniae isolates were PKS-positive out of which 50% were hvKp strains. The majority of the isolates were from the more virulent serotype of K1 (30%) and K2 (50%). PKS-positive K. pneumoniae isolates did not possess genes to confer carbapenem resistance but instead were more highly associated with siderophore genes (aerobactin, enterobactin, and yersiniabactin) and allantoin metabolism genes (allS, allS2). Cell proliferation in primary colon, SW1116 (Stage I), and SW480 (Stage II) CRC cell lines were enhanced when co-cultured with PKS-positive K. pneumoniae antigens. ECIS revealed enhanced cell proliferation upon recurrent antigen exposure. This demonstrates the possible role that PKS-positive K. pneumoniae has in exacerbating CRC progression.
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11
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Chen Q, Zhang Y, Zhang L, Xian S, Huang L, Ding X, Wu H, Xia H, Yang X, Cai X. Liver abscess complicated with multiple organ invasive infection caused by hematogenous disseminated hypervirulent Klebsiella pneumoniae: A case report. Open Med (Wars) 2023; 18:20230694. [PMID: 37034501 PMCID: PMC10080706 DOI: 10.1515/med-2023-0694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/13/2023] [Accepted: 03/19/2023] [Indexed: 04/11/2023] Open
Abstract
Hypervirulent Klebsiella pneumoniae (hvKp) causes increasing infections in healthy individuals from the community. In severe cases, it can cause multiple organ infection with invasive metastasis of blood sources, seriously threatening the patients' life. Rapid and accurate diagnosis of the pathogen becomes the key to timely antibiotic treatment to improve the prognosis. This article reports a case of liver abscess complicated with multiple organ invasive infection caused by hematogenous-disseminated hvKp. K. pneumoniae was identified by culture and metagenomic next-generation sequencing (mNGS) using blood and liver abscess drainage fluid. The isolates from the two samples were subsequently identified with high homology (99.999%) by whole genome sequencing. In addition, multiple virulence genes were detected in the two isolates and the string test was positive, indicating hvKp with hypermucoviscosity phenotype. Multiple antibiotic treatments were given. The conditions of the patient were stable but the temperature remained high. Surgical drainage treatment was performed, and the patient's body temperature immediately dropped to normal. He finally recovered after 6 months of follow-up. mNGS using body fluids can facilitate the rapid diagnosis of pathogens. For hvKp infection, choosing a better antibiotic therapy and receiving surgical drainage can significantly improve the prognosis of the patient.
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Affiliation(s)
- Qingyun Chen
- Department of Respiratory and Critical Care Medicine, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China
| | - Ye Zhang
- Department of Scientific Affairs, Hugobiotech Co., Ltd., Beijing 100176, China
| | - Lei Zhang
- Department of Respiratory and Critical Care Medicine, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China
| | - Shaojing Xian
- Department of Respiratory and Critical Care Medicine, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China
| | - Linhui Huang
- Department of Respiratory and Critical Care Medicine, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China
| | - Xiuxiu Ding
- Department of Respiratory and Critical Care Medicine, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China
| | - Hua Wu
- Clinical Laboratory, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China
| | - Han Xia
- Department of Scientific Affairs, Hugobiotech Co., Ltd., Beijing 100176, China
| | - Xuying Yang
- Department of Scientific Affairs, Hugobiotech Co., Ltd., Beijing 100176, China
| | - Xingjun Cai
- Department of Respiratory and Critical Care Medicine, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570311, China
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12
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Dai P, Hu D. The making of hypervirulent Klebsiella pneumoniae. J Clin Lab Anal 2022; 36:e24743. [PMID: 36347819 PMCID: PMC9757020 DOI: 10.1002/jcla.24743] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/01/2022] [Accepted: 10/09/2022] [Indexed: 10/08/2023] Open
Abstract
Klebsiella pneumoniae is a notorious bacterium in clinical practice. Virulence, carbapenem-resistance and their convergence among K. pneumoniae are extensively discussed in this article. Hypervirulent K. pneumoniae (HvKP) has spread from the Asian Pacific Rim to the world, inducing various invasive infections, such as pyogenic liver abscess, endophthalmitis, and meningitis. Furthermore, HvKP has acquired more and more drug resistance. Among multidrug-resistant HvKP, hypervirulent carbapenem-resistant K. pneumoniae (Hv-CRKP), and carbapenem-resistant hypervirulent K. pneumoniae (CR-HvKP) are both devastating for their extreme drug resistance and virulence. The hypervirulence of HvKP is primarily attributed to hypercapsule, macromolecular exopolysaccharides, or excessive siderophores, although it has many other factors, for example, lipopolysaccharides, fimbriae, and porins. In contrast with classical determination of HvKP, that is, animal lethality test, molecular determination could be an optional and practical method after improvement. HvKP, including Hv-CRKP and CR-HvKP, has been progressing. R-M and CRISPR-Cas systems may play pivotal roles in such evolutions. Hv-CRKP and CR-HvKP, in particular the former, should be of severe concern due to their being more and more prevalent.
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Affiliation(s)
- Piaopiao Dai
- Department of Laboratory MedicineTaizhou Municipal HospitalTaizhouChina
| | - Dakang Hu
- Department of Laboratory MedicineTaizhou Municipal HospitalTaizhouChina
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13
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Wu J, Chen J, Wang Y, Meng Q, Zhao J. Siderophore iucA of hypermucoviscous Klebsiella pneumoniae promotes liver damage in mice by inducing oxidative stress. Biochem Biophys Rep 2022; 32:101376. [PMID: 36340868 PMCID: PMC9634269 DOI: 10.1016/j.bbrep.2022.101376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 10/25/2022] [Accepted: 10/26/2022] [Indexed: 11/06/2022] Open
Abstract
The hypermucoviscosity/hypervirulent K. pneumoniae (hvKP) is a dominant cause of pyogenic liver abscess (PLA) and has contributed to the endemicity of disease in Asian country. The siderophore aerobactin (iucA) is highly expressed in hvKP and acting virulence role during hvKP infection. However, its role in the PLA is poorly understood. We constructed iucA deletion mutant (ΔiucA-hvKP852) and used animal study to characterize the role of siderophore iucA in K. pneumoniae liver abscess. The animal experiments showed that ΔiucA-hvKP852 strain had lower virulence in mice compared to hvKP852 wild type strain. At 24 h after infection, only two of ten mice developed liver abscess during infection with ΔiucA-hvKP852 strain, while nine of ten mice infected with wild type hvKP852 strain showed multiple lesions of liver abscess. The liver tissue infected with ΔiucA-hvKP852 exhibited low reactive oxygen stress levels compared to those infected by wild type hvKP852 strain (P < 0.05). The results suggest that siderophore iucA play an important role in the liver abscess by inducing oxidative stress. iucA positive strains produces more siderophore than iucA negative hvK. pneumoniae. Siderophore production is positively related with Oxidative stress in hvK. pneumoniae. iucA enhances oxidative stress in liver and forms liver abscess during hvK. pneumoniae infection.
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Affiliation(s)
- Jinyin Wu
- Wu Lien Teh Institute, Department of Microbiology, Harbin Medical University, 157, Baojian Road, Nangang District, Harbin, 150081, China
| | - Jie Chen
- Wu Lien Teh Institute, Department of Microbiology, Harbin Medical University, 157, Baojian Road, Nangang District, Harbin, 150081, China
| | - Ying Wang
- Wu Lien Teh Institute, Department of Microbiology, Harbin Medical University, 157, Baojian Road, Nangang District, Harbin, 150081, China
| | - Qingtai Meng
- Wu Lien Teh Institute, Department of Microbiology, Harbin Medical University, 157, Baojian Road, Nangang District, Harbin, 150081, China
| | - Jizi Zhao
- Wu Lien Teh Institute, Department of Microbiology, Harbin Medical University, 157, Baojian Road, Nangang District, Harbin, 150081, China,Heilongjiang Provincial Key Laboratory of Infection and Immunity, Pathogen Biology, Harbin, China,Corresponding author. Wu Lien Teh Institute, Department of Microbiology, Harbin Medical University, 157, Baojian Road, Nangang District, Harbin, 150081, China.
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14
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Sydow K, Eger E, Schwabe M, Heiden SE, Bohnert JA, Franzenburg S, Jurischka C, Schierack P, Schaufler K. Geno- and Phenotypic Characteristics of a Klebsiella pneumoniae ST20 Isolate with Unusual Colony Morphology. Microorganisms 2022; 10:microorganisms10102063. [PMID: 36296341 PMCID: PMC9606995 DOI: 10.3390/microorganisms10102063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/10/2022] [Accepted: 10/16/2022] [Indexed: 11/16/2022] Open
Abstract
Klebsiella pneumoniae is a common member of the intestinal flora of vertebrates. In addition to opportunistic representatives, hypervirulent (hvKp) and antibiotic-resistant K. pneumoniae (ABR-Kp) occur. While ABR-Kp isolates often cause difficult-to-treat diseases due to limited therapeutic options, hvKp is a pathotype that can infect healthy individuals often leading to recurrent infection. Here, we investigated the clinical K. pneumoniae isolate PBIO3459 obtained from a blood sample, which showed an unusual colony morphology. By combining whole-genome and RNA sequencing with multiple in vitro and in vivo virulence-associated assays, we aimed to define the respective Klebsiella subtype and explore the unusual phenotypic appearance. We demonstrate that PBIO3459 belongs to sequence type (ST)20 and carries no acquired resistance genes, consistent with phenotypic susceptibility tests. In addition, the isolate showed low-level virulence, both at genetic and phenotypic levels. We thus suggest that PBIO3459 is an opportunistic (commensal) K. pneumoniae isolate. Genomic comparison of PBIO3459 with closely related ABR-Kp ST20 isolates revealed that they differed only in resistance genes. Finally, the unusual colony morphology was mainly associated with carbohydrate and amino acid transport and metabolism. In conclusion, our study reveals the characteristics of a Klebsiella sepsis isolate and suggests that opportunistic representatives likely acquire and accumulate antibiotic resistances that subsequently enable their emergence as ABR-Kp pathogens.
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Affiliation(s)
- Katharina Sydow
- Pharmaceutical Microbiology, Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
| | - Elias Eger
- Institute of Infection Medicine, Christian-Albrecht University Kiel and University Medical Center Schleswig-Holstein, 24105 Kiel, Germany
| | - Michael Schwabe
- Pharmaceutical Microbiology, Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
| | - Stefan E. Heiden
- Pharmaceutical Microbiology, Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
| | - Jürgen A. Bohnert
- Friedrich Loeffler-Institute of Medical Microbiology, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Sören Franzenburg
- Institute of Clinical Molecular Biology, Christian-Albrecht University Kiel and University Medical Center Schleswig-Holstein, 24105 Kiel, Germany
| | - Christoph Jurischka
- Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, 01968 Senftenberg, Germany
| | - Peter Schierack
- Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, 01968 Senftenberg, Germany
| | - Katharina Schaufler
- Pharmaceutical Microbiology, Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
- Institute of Infection Medicine, Christian-Albrecht University Kiel and University Medical Center Schleswig-Holstein, 24105 Kiel, Germany
- Correspondence: ; Tel.: +49-3834-420-4869
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15
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Characterization of Novel Bacteriophage vB_KpnP_ZX1 and Its Depolymerases with Therapeutic Potential for K57 Klebsiella pneumoniae Infection. Pharmaceutics 2022; 14:pharmaceutics14091916. [PMID: 36145665 PMCID: PMC9505181 DOI: 10.3390/pharmaceutics14091916] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/04/2022] [Accepted: 09/08/2022] [Indexed: 11/17/2022] Open
Abstract
A novel temperate phage vB_KpnP_ZX1 was isolated from hospital sewage samples using the clinically derived K57-type Klebsiella pneumoniae as a host. Phage vB_KpnP_ZX1, encoding three lysogen genes, the repressor, anti-repressor, and integrase, is the fourth phage of the genus Uetakevirus, family Podoviridae, ever discovered. Phage vB_KpnP_ZX1 did not show ideal bactericidal effect on K. pneumoniae 111-2, but TEM showed that the depolymerase Dep_ZX1 encoded on the short tail fiber protein has efficient capsule degradation activity. In vitro antibacterial results show that purified recombinant Dep_ZX1 can significantly prevent the formation of biofilm, degrade the formed biofilm, and improve the sensitivity of the bacteria in the biofilm to the antibiotics kanamycin, gentamicin, and streptomycin. Furthermore, the results of animal experiments show that 50 µg Dep_ZX1 can protect all K. pneumoniae 111-2-infected mice from death, whereas the control mice infected with the same dose of K. pneumoniae 111-2 all died. The degradation activity of Dep_ZX1 on capsular polysaccharide makes the bacteria weaken their resistance to immune cells, such as complement-mediated serum killing and phagocytosis, which are the key factors for its therapeutic action. In conclusion, Dep_ZX1 is a promising anti-virulence agent for the K57-type K. pneumoniae infection or biofilm diseases.
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16
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Han R, Niu M, Liu S, Mao J, Yu Y, Du Y. The effect of siderophore virulence genes entB and ybtS on the virulence of Carbapenem-resistant Klebsiella pneumoniae. Microb Pathog 2022; 171:105746. [PMID: 36064103 DOI: 10.1016/j.micpath.2022.105746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 07/27/2022] [Accepted: 08/29/2022] [Indexed: 11/25/2022]
Abstract
OBJECTIVE With the detection rate increasing each year, highly resistant and virulent CRKP has been a serious challenge to clinical treatment because of the high morbidity and mortality. Considering the virulence of CRKP is closely related to over-expression of siderophore, the high detection rate of entB and ybtS genes in highly virulent CRKP may be an important reason for the high virulence phenotype of CRKP. Therefore, in this study, single/double knockout and complemented strains of siderophore virulence genes entB and ybtS were constructed to clarify the effect of siderophore virulence genes on the virulence of CRKP. METHODS 1.The wire drawing experiment, mucus phenotype screening experiment, and PCR amplification were used to screen the target strain WT. the entB gene deletion strain △entB and the complementation strain C-△entB, ybtS gene deletion strain ΔybtS and complementation strain C-ΔybtS, entB and ybtS double gene deletion strain ΔentB + ybtS and complementation strain C-ΔentB + ybtS,were constructed by CrispR-Cas9 gene editing technology. PCR method was used to test whether the knockout and complementation were successful. 2. The colony morphology and mucus phenotype of the experimental strains were observed and the siderophore ability of the experimental strains was tested. Then the growth curves, biofilm-forming ability, and anti-serum killing ability of the strains were determined. 3. In order to understand the virulence of the experimental strain, the mouse intraperitoneal infection model was established to draw the survival curves and determine LD50 of experiment strains. Then to clarify the colonization ability of the experimental strains in the lung and liver of mice, the pathological biopsies were used to observe histopathological changes and ELISA method was used to determine the inflammatory factors IL-1β, LI-3 and TNF-α. RESULTS 1 CRKP-27 was screened as the target strain WT, which is characterized by positive wire drawing test, strong mucus, strong virulence and carrying both entB and ybtS genes. The single/double knockout and complemented strains of siderophore virulence genes entB and ybtS were successfully constructed. 2 Siderophore virulence genes entB and ybtS had no significant effect on the colony morphology, mucus phenotype (drawing test) and biofilm formation ability of CRKP strains. The CRKP strains with entB and ybtS genes could significantly increase siderophore production. Although both the entB and ybtS genes could impair the growth rate of the CRKP strain, the role of ybtS gene was relatively slow. entB and ybtS genes enhanced the antiserum killing ability of CRKP strains. 3 The presence of entB and ybtS genes reduced the survival rate of mice infected with CRKP strains. Histopathological changes and inflammatory factor levels in the lungs and livers of infected mice were enhanced by the presence of entB and ybtS genes. Mice infected with the same strain had higher histopathological changes and levels of inflammatory factors in the lungs than in the livers. CONCLUSIONS 1.The siderophore virulence genes entB and ybtS have no significant effect on the colony morphology, mucus phenotype and biofilm formation ability of CRKP strains.2.The siderophore virulence genes entB and ybtS can significantly enhance the virulence of the CRKP strain, but weaken its growth ability.
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Affiliation(s)
- Ruihui Han
- Yunnan Key Laboratory of Laboratory Medicine, Kunming, 650032, China; Yunnan Province Clinical Research Center for Laboratory Medicine, Kunming, 650032, China; Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China
| | - Min Niu
- Yunnan Key Laboratory of Laboratory Medicine, Kunming, 650032, China; Yunnan Province Clinical Research Center for Laboratory Medicine, Kunming, 650032, China; Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China
| | - Shumin Liu
- Yunnan Key Laboratory of Laboratory Medicine, Kunming, 650032, China; Yunnan Province Clinical Research Center for Laboratory Medicine, Kunming, 650032, China; Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China
| | - Jian Mao
- Yunnan Key Laboratory of Laboratory Medicine, Kunming, 650032, China; Yunnan Province Clinical Research Center for Laboratory Medicine, Kunming, 650032, China; Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China
| | - Yan Yu
- YAN'AN Hospital of Kunming City, China
| | - Yan Du
- Yunnan Key Laboratory of Laboratory Medicine, Kunming, 650032, China; Yunnan Province Clinical Research Center for Laboratory Medicine, Kunming, 650032, China; Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China.
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17
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Li F, Zheng W, Yu J, Zhao L. Klebsiella pneumoniae liver abscess with purulent meningitis and endogenous endophthalmitis: A case report. Front Surg 2022; 9:894929. [PMID: 36090343 PMCID: PMC9448882 DOI: 10.3389/fsurg.2022.894929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 07/21/2022] [Indexed: 11/20/2022] Open
Abstract
This is a rare but typical case of a Klebsiella pneumoniae liver abscess with migratory infections including purulent meningitis and endogenous endophthalmitis. The patient had a chief complaint of 7 days of fever, 4 days of blurry vision, and 4 h of glossolalia. Ultrasound scan and computed tomography (CT) suggested a liver abscess. Both blood and drainage fluid cultures grew K. pneumoniae with a high mucosal phenotype. The patient was finally diagnosed with a K. pneumoniae liver abscess, purulent meningitis, and endogenous K. pneumoniae endophthalmitis in the right eye. Ultrasound-guided percutaneous catheter drainage (PCD) of the liver abscess was performed, and meropenem was used to control infection. The patient was given 0.1 ml of vancomycin (10 g/L) and 0.1 ml of ceftazidime (20 g/L) were by intravitreal injection for the treatment of endophthalmitis. The infection was gradually controlled after such treatments. The patient was discharged from our hospital with an improved condition. However, during the time of follow-up, she developed complications due to severe pneumonia and eventually died in a local hospital. This case revealed that a rapid diagnosis followed by appropriate treatment would improve prognosis and prevent severe metastatic complications.
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Affiliation(s)
- Fang Li
- Department of Stroke Center, Dalian Municipal Central Hospital, Dalian, China
| | - Wenfei Zheng
- Department of Critical Care Medicine, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Jian Yu
- Department of Critical Care Medicine, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
- Correspondence: Zhao Linyan Yu Jian
| | - Linyan Zhao
- Department of Critical Care Medicine, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
- Correspondence: Zhao Linyan Yu Jian
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18
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Characterization of Hypervirulent Klebsiella pneumoniae (Hv-Kp): Correlation of Virulence with Antimicrobial Susceptibility. Int J Microbiol 2022; 2022:4532707. [PMID: 36032181 PMCID: PMC9410983 DOI: 10.1155/2022/4532707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 06/23/2022] [Accepted: 07/20/2022] [Indexed: 11/17/2022] Open
Abstract
Introduction Hypervirulent K. pneumoniae (Hv-Kp) is an emerging variant of classical K. pneumoniae (C-Kp) that exhibits hypermucoviscocity and possesses multiple siderophores as virulence factors and is known to cause serious debilitating infections in immunocompetent individuals. Aim and objective. The aim of this study is to identify C-Kp and Hv-Kp strains and detect their virulence factors and antimicrobial susceptibility patterns. Materials and Methods A total of 129 K. pneumoniae isolates from different clinical samples were used for the identification and differentiation of classical K. pneumoniae (C-Kp) and hypervirulent K. pneumoniae (Hv-Kp) to correlate their virulence with antimicrobial susceptibility patterns and identify their risk factors. Hypermucoviscosity was determined by a string test (>5 mm of string length). The aerobactin gene was detected by PCR. Results and Conclusion. In total, 13.9% (18/129) were Hv-Kp and 86.1% (111/129) were C-Kp. Only 50% (9/18) of the Hv-Kp isolates were hypermucoviscous. C-Kp was significantly more resistant to antimicrobials than Hv-Kp. Among C-Kp, 75.7% were ESBL producers and 76.6% were multidrug resistant while in Hv-Kp, 44.44% were both ESBL producers and multidrug-resistant which is statistically significant (P < 0.01). Diabetes was a common risk factor for C-Kp infections whereas, respiratory disorders like COPD and prolonged ICU stay were the risk factors for Hv-Kp infections. The mortality rate among patients with Hv-Kp infections (87.5%) was significantly high when compared to that of C-Kp infections (35.7%) (P < 0.001). A majority of hypermucoviscous K. pneumoniae isolates were multidrug resistant (65.2%). Although the prevalence of Hv-Kp infections was low, a high percentage of them were multidrug resistant with a significantly high mortality rate. Hence, it is important to efficiently identify Hv-Kp strains from clinical samples and determine their antimicrobial susceptibility patterns, so as to provide immediate and effective treatment and to prevent possible outbreaks.
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19
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Kochan TJ, Nozick SH, Medernach RL, Cheung BH, Gatesy SWM, Lebrun-Corbin M, Mitra SD, Khalatyan N, Krapp F, Qi C, Ozer EA, Hauser AR. Genomic surveillance for multidrug-resistant or hypervirulent Klebsiella pneumoniae among United States bloodstream isolates. BMC Infect Dis 2022; 22:603. [PMID: 35799130 PMCID: PMC9263067 DOI: 10.1186/s12879-022-07558-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 06/21/2022] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Klebsiella pneumoniae strains have been divided into two major categories: classical K. pneumoniae, which are frequently multidrug-resistant and cause hospital-acquired infections in patients with impaired defenses, and hypervirulent K. pneumoniae, which cause severe community-acquired and disseminated infections in normal hosts. Both types of infections may lead to bacteremia and are associated with significant morbidity and mortality. The relative burden of these two types of K. pneumoniae among bloodstream isolates within the United States is not well understood. METHODS We evaluated consecutive K. pneumoniae isolates cultured from the blood of hospitalized patients at Northwestern Memorial Hospital (NMH) in Chicago, Illinois between April 2015 and April 2017. Bloodstream isolates underwent whole genome sequencing, and sequence types (STs), capsule loci (KLs), virulence genes, and antimicrobial resistance genes were identified in the genomes using the bioinformatic tools Kleborate and Kaptive. Patient demographic, comorbidity, and infection information, as well as the phenotypic antimicrobial resistance of the isolates were extracted from the electronic health record. Candidate hypervirulent isolates were tested in a murine model of pneumonia, and their plasmids were characterized using long-read sequencing. We also extracted STs, KLs, and virulence and antimicrobial resistance genes from the genomes of bloodstream isolates submitted from 33 United States institutions between 2007 and 2021 to the National Center for Biotechnology Information (NCBI) database. RESULTS Consecutive K. pneumoniae bloodstream isolates (n = 104, one per patient) from NMH consisted of 75 distinct STs and 51 unique capsule loci. The majority of these isolates (n = 58, 55.8%) were susceptible to all tested antibiotics except ampicillin, but 17 (16.3%) were multidrug-resistant. A total of 32 (30.8%) of these isolates were STs of known high-risk clones, including ST258 and ST45. In particular, 18 (17.3%) were resistant to ceftriaxone (of which 17 harbored extended-spectrum beta-lactamase genes) and 9 (8.7%) were resistant to meropenem (all of which harbored a carbapenemase genes). Four (3.8%) of the 104 isolates were hypervirulent K. pneumoniae, as evidenced by hypermucoviscous phenotypes, high levels of virulence in a murine model of pneumonia, and the presence of large plasmids similar to characterized hypervirulence plasmids. These isolates were cultured from patients who had not recently traveled to Asia. Two of these hypervirulent isolates belonged to the well characterized ST23 lineage and one to the re-emerging ST66 lineage. Of particular concern, two of these isolates contained plasmids with tra conjugation loci suggesting the potential for transmission. We also analyzed 963 publicly available genomes of K. pneumoniae bloodstream isolates from locations within the United States. Of these, 465 (48.3%) and 760 (78.9%) contained extended-spectrum beta-lactamase genes or carbapenemase genes, respectively, suggesting a bias towards submission of antibiotic-resistant isolates. The known multidrug-resistant high-risk clones ST258 and ST307 were the predominant sequence types. A total of 32 (3.3%) of these isolates contained aerobactin biosynthesis genes and 26 (2.7%) contained at least two genetic features of hvKP strains, suggesting elevated levels of virulence. We identified 6 (0.6%) isolates that were STs associated with hvKP: ST23 (n = 4), ST380 (n = 1), and ST65 (n = 1). CONCLUSIONS Examination of consecutive isolates from a single center demonstrated that multidrug-resistant high-risk clones are indeed common, but a small number of hypervirulent K. pneumoniae isolates were also observed in patients with no recent travel history to Asia, suggesting that these isolates are undergoing community spread in the United States. A larger collection of publicly available bloodstream isolate genomes also suggested that hypervirulent K. pneumoniae strains are present but rare in the USA; however, this collection appears to be heavily biased towards highly antibiotic-resistant isolates (and correspondingly away from hypervirulent isolates).
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Affiliation(s)
- Travis J Kochan
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA.
| | - Sophia H Nozick
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Rachel L Medernach
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA.,Division of Infectious Diseases, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Bettina H Cheung
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Samuel W M Gatesy
- Division of Infectious Diseases, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Marine Lebrun-Corbin
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Sumitra D Mitra
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Natalia Khalatyan
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Fiorella Krapp
- Division of Infectious Diseases, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Chao Qi
- Department of Pathology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Egon A Ozer
- Division of Infectious Diseases, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA.,Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Alan R Hauser
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA.,Division of Infectious Diseases, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
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20
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Zhang Y, Xu Y, Huang Y. Virulence Genotype and Correlation of Clinical Severeness with Presence of the Type VI Secretion System in Klebsiella pneumoniae Isolates Causing Bloodstream Infections. Infect Drug Resist 2022; 15:1487-1497. [PMID: 35411154 PMCID: PMC8994602 DOI: 10.2147/idr.s353858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 03/26/2022] [Indexed: 11/23/2022] Open
Abstract
Background Klebsiella pneumoniae (K. pneumoniae) causes bloodstream infection (BSI), which is responsible for a high rate of morbidity and mortality among different populations. In mainland China, data on the correlation and features of the type VI secretion system (T6SS) gene cluster in K. pneumoniae is currently scarce. As a result, we conducted a prospective investigation to determine the involvement of the T6SS in K. pneumoniae pathogenicity and antibiotic resistance. Methods In this prospective analysis, we enrolled 119 individuals who had been diagnosed with K. pneumoniae bloodstream infection between July 2019 and January 2021 and acquired demographic and clinical data from their medical records. The virulence genes rmpA, rmpA2, aerobactin, iroB, hcp, vgrG, and icmF were tested for K1 and K2, antimicrobial susceptibility. Five T6SS-positive and five T6SS-negative isolates were chosen for the competition, serum resistance, and biofilm formation experiments to further gain insights regarding the microbiological properties of T6SS-positive K. pneumoniae isolates. Results Among 119 isolates obtained from patients with BSIs, 20 (16.8%) were T6SS positive K. pneumoniae. T6SS positive strains had four virulence genes and a greater K1 capsular serotypes rate than T6SS negative bacteria. Among hvKP isolates, the T6SS positive rate was substantially greater than the T6SS negative rate (P = 0.001). T6SS-positive K. pneumoniae strains had a lower rate of antimicrobial resistance in comparison to T6SS-negative bacteria. T6SS-positive isolates may be more competitive with Escherichia coli than T6SS-negative isolates. T6SS-positive isolates, on the other hand, did not show stronger biofilm-forming activity or a higher survival rate in the presence of normal human serum in comparison to T6SS-negative isolates. Conclusion T6SS-positive K. pneumoniae was common in people who had BSIs. In T6SS‐containing K. pneumoniae, the system may play a major role in bacterial competition.
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Affiliation(s)
- Yin Zhang
- Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China
| | - Yuanhong Xu
- Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China
| | - Ying Huang
- Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China
- Correspondence: Ying Huang; Yuanhong Xu, Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China, Email ;
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21
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Genetic Diversity and Pathogenic Features in Klebsiella pneumoniae Isolates from Patients with Pyogenic Liver Abscess and Pneumonia. Microbiol Spectr 2022; 10:e0264621. [PMID: 35352958 PMCID: PMC9045331 DOI: 10.1128/spectrum.02646-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
While Klebsiella pneumoniae is a common cause of nosocomial and community-acquired infections, including pneumonia and pyogenic liver abscess, little is known about the population structure of this bacterium. In this study, we investigated the prevalence and molecular characteristics of K. pneumoniae isolates from carriers, pyogenic liver abscess patients, and pneumonia patients, and genomic and phenotypic assays were used to determine the differences among the isolates. A total of 232 K. pneumoniae isolates were subtyped into 74 sequence types (STs). The isolates from different sources had their own STs, and the predominant subtypes in liver abscess and pneumonia patients were ST23 and ST11, respectively. Pangenome analysis also distinguished three phylogroups that were consistent with the isolate sources. The isolates collected from liver abscess patients carried significantly more virulence factors, and those from pneumonia patients harbored significantly more resistance genes and replicons. Almost all isolate STs (93/97 [95.88%]) from liver abscesses strongly correlated with the virulence factor salmochelin, while most pneumonia isolate STs (52/53 [98.11%]) from pneumonia did not correlate with salmochelin. The isolates collected from liver abscesses showed higher virulence in the cytotoxicity and mouse models. These data provide genomic support for the proposal that isolates collected from carriers, liver abscess patients, and pneumonia patients have distinct genomic features. Isolates from the different sources are largely nonoverlapping, suggesting that different patients may be infected via different sources. Further studies on the pathogenic mechanisms of salmochelin and other virulence factors will be required. IMPORTANCE While Klebsiella pneumoniae is a common cause of nosocomial and community-acquired infections, including pneumonia and pyogenic liver abscess, little is known about the population structure of this bacterium. We collected 232 isolates from carriers, pyogenic liver abscess patients, and pneumonia patients, and the isolates from different sources had their own sequence types. Pangenome analysis also distinguished three phylogroups that were consistent with the isolate sources. The isolates collected from liver abscess patients carried significantly more virulence factors, and those from pneumonia patients harbored significantly more resistance genes and replicons. Besides, there was a strong link between salmochelin and liver abscess. The isolates collected from liver abscesses also showed higher virulence in the cytotoxicity and mouse models. Isolates collected from different sources have distinct genomic features, suggesting that different patients may be infected via different sources.
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22
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Kumar A, Yang T, Chakravorty S, Majumdar A, Nairn BL, Six DA, Marcondes Dos Santos N, Price SL, Lawrenz MB, Actis LA, Marques M, Russo TA, Newton SM, Klebba PE. Fluorescent sensors of siderophores produced by bacterial pathogens. J Biol Chem 2022; 298:101651. [PMID: 35101443 PMCID: PMC8921320 DOI: 10.1016/j.jbc.2022.101651] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/25/2022] Open
Abstract
Siderophores are iron-chelating molecules that solubilize Fe3+ for microbial utilization and facilitate colonization or infection of eukaryotes by liberating host iron for bacterial uptake. By fluorescently labeling membrane receptors and binding proteins, we created 20 sensors that detect, discriminate, and quantify apo- and ferric siderophores. The sensor proteins originated from TonB-dependent ligand-gated porins (LGPs) of Escherichia coli (Fiu, FepA, Cir, FhuA, IutA, BtuB), Klebsiella pneumoniae (IroN, FepA, FyuA), Acinetobacter baumannii (PiuA, FepA, PirA, BauA), Pseudomonas aeruginosa (FepA, FpvA), and Caulobacter crescentus (HutA) from a periplasmic E. coli binding protein (FepB) and from a human serum binding protein (siderocalin). They detected ferric catecholates (enterobactin, degraded enterobactin, glucosylated enterobactin, dihydroxybenzoate, dihydroxybenzoyl serine, cefidericol, MB-1), ferric hydroxamates (ferrichromes, aerobactin), mixed iron complexes (yersiniabactin, acinetobactin, pyoverdine), and porphyrins (hemin, vitamin B12). The sensors defined the specificities and corresponding affinities of the LGPs and binding proteins and monitored ferric siderophore and porphyrin transport by microbial pathogens. We also quantified, for the first time, broad recognition of diverse ferric complexes by some LGPs, as well as monospecificity for a single metal chelate by others. In addition to their primary ferric siderophore ligands, most LGPs bound the corresponding aposiderophore with ∼100-fold lower affinity. These sensors provide insights into ferric siderophore biosynthesis and uptake pathways in free-living, commensal, and pathogenic Gram-negative bacteria.
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Affiliation(s)
- Ashish Kumar
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Taihao Yang
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Somnath Chakravorty
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA; Department of Medicine, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo School of Medicine, Buffalo, New York, USA
| | - Aritri Majumdar
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Brittany L Nairn
- Department of Biological Sciences, Bethel University, St. Paul, Minnesota, USA
| | - David A Six
- Department of Biology, Venatorx Pharmaceuticals, Inc, Malvern, Pennsylvania, USA
| | - Naara Marcondes Dos Santos
- Departamento de Microbiologia, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil
| | - Sarah L Price
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, Kentucky, USA
| | - Matthew B Lawrenz
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, Kentucky, USA
| | - Luis A Actis
- Department of Microbiology, Miami University, Oxford, Ohio, USA
| | - Marilis Marques
- Departamento de Microbiologia, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil
| | - Thomas A Russo
- Department of Medicine, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo School of Medicine, Buffalo, New York, USA
| | - Salete M Newton
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA
| | - Phillip E Klebba
- Department of Biochemistry & Molecular Biophysics, Kansas State University, Manhattan, Kansas, USA.
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23
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Roberge N, Neville N, Douchant K, Noordhof C, Boev N, Sjaarda C, Sheth PM, Jia Z. Broad-Spectrum Inhibitor of Bacterial Polyphosphate Homeostasis Attenuates Virulence Factors and Helps Reveal Novel Physiology of Klebsiella pneumoniae and Acinetobacter baumannii. Front Microbiol 2021; 12:764733. [PMID: 34764949 PMCID: PMC8576328 DOI: 10.3389/fmicb.2021.764733] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/04/2021] [Indexed: 12/26/2022] Open
Abstract
Acinetobacter baumannii and Klebsiella pneumoniae currently rank amongst the most antibiotic-resistant pathogens, responsible for millions of infections each year. In the wake of this crisis, anti-virulence therapeutics targeting bacterial polyphosphate (polyP) homeostasis have been lauded as an attractive alternative to traditional antibiotics. In this work, we show that the small molecule gallein, a known G-protein βγ subunit modulator, also recently proven to have dual-specificity polyphosphate kinase (PPK) inhibition in Pseudomonas aeruginosa, in turn exhibits broad-spectrum PPK inhibition in other priority pathogens. Gallein treatment successfully attenuated virulence factors of K. pneumoniae and A. baumannii including biofilm formation, surface associated motility, and offered protection against A. baumannii challenge in a Caenorhabditis elegans model of infection. This was highlighted most importantly in the critically understudied A. baumannii, where gallein treatment phenocopied a ppk1 knockout strain of a previously uncharacterized PPK1. Subsequent analysis revealed a unique instance of two functionally and phenotypically distinct PPK1 isoforms encoded by a single bacterium. Finally, gallein was administered to a defined microbial community comprising over 30 commensal species of the human gut microbiome, demonstrating the non-disruptive properties characteristic of anti-virulence treatments as microbial biodiversity was not adversely influenced. Together, these results emphasize that gallein is a promising avenue for the development of broad-spectrum anti-virulence therapeutics.
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Affiliation(s)
- Nathan Roberge
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
| | - Nolan Neville
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
| | - Katya Douchant
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada.,Gastrointestinal Disease Research Unit (GIDRU), Department of Medicine, Queen's University, Kingston, ON, Canada
| | - Curtis Noordhof
- Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada.,Gastrointestinal Disease Research Unit (GIDRU), Department of Medicine, Queen's University, Kingston, ON, Canada
| | - Nadejda Boev
- Queen's Genomics Lab at Ongwanada (Q-GLO), Ongwanada Resource Center, Kingston, ON, Canada
| | - Calvin Sjaarda
- Queen's Genomics Lab at Ongwanada (Q-GLO), Ongwanada Resource Center, Kingston, ON, Canada.,Department of Psychiatry, Queen's University, Kingston, ON, Canada
| | - Prameet M Sheth
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada.,Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada.,Gastrointestinal Disease Research Unit (GIDRU), Department of Medicine, Queen's University, Kingston, ON, Canada.,Division of Microbiology, Kingston Health Science Center, Kingston, ON, Canada
| | - Zongchao Jia
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
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24
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Ballén V, Gabasa Y, Ratia C, Ortega R, Tejero M, Soto S. Antibiotic Resistance and Virulence Profiles of Klebsiella pneumoniae Strains Isolated From Different Clinical Sources. Front Cell Infect Microbiol 2021; 11:738223. [PMID: 34540722 PMCID: PMC8440954 DOI: 10.3389/fcimb.2021.738223] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/16/2021] [Indexed: 11/26/2022] Open
Abstract
Klebsiella pneumoniae is a Gram-negative bacterium capable of colonizing, invading, and causing infections in different anatomical sites of the human body. Its ability to evade the immune system, its increasing antimicrobial resistance and the emergence of hypervirulent pathotypes have become a major challenge in the medical field. In this study, 127 strains from different clinical sources (urine, respiratory tract or blood) were characterized for antimicrobial resistance, the presence of virulence factor genes, serum resistance, hypermucoviscosity and the ability to form biofilms. Specific characteristics of the uropathogenic strains were examined and compared with the other clinical groups. Differences were found between urine and the other groups of strains. Urine strains showed the highest antibiotic resistance (64.91%) compared to blood (63.64%) or respiratory strains (51.35%) as well as the highest extended-spectrum beta-lactamases (ESBL) production. These strains also showed statistically significant high resistance to fosfomycin (24.56%) compared to the other groups (p = 0.008). Regarding virulence, 84.21% of the urine strains presented the uge gene, showing a statistically significant difference (p = 0.03) compared to the other clinical sources, indicating a possible role of this gene in the development of urinary tract infection. In addition, 46% of biofilm-forming strains belonged to the urine sample group (p = 0.043). In conclusion, K. pneumoniae strains isolated from urine samples showed higher antimicrobial resistance, ESBL production, and biofilm-forming ability compared to those isolated from respiratory or blood samples. The rapid spread of clinical strains with these characteristics is of concern, and new therapeutic alternatives are essential to mitigate their harmful effects.
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Affiliation(s)
- Victoria Ballén
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Yaiza Gabasa
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Carlos Ratia
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Raquel Ortega
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Marc Tejero
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Sara Soto
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
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25
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Functionalized Chitosan Nanomaterials: A Jammer for Quorum Sensing. Polymers (Basel) 2021; 13:polym13152533. [PMID: 34372136 PMCID: PMC8348235 DOI: 10.3390/polym13152533] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 07/23/2021] [Accepted: 07/25/2021] [Indexed: 12/02/2022] Open
Abstract
The biggest challenge in the present-day healthcare scenario is the rapid emergence and spread of antimicrobial resistance due to the rampant use of antibiotics in daily therapeutics. Such drug resistance is associated with the enhancement of microbial virulence and the acquisition of the ability to evade the host’s immune response under the shelter of a biofilm. Quorum sensing (QS) is the mechanism by which the microbial colonies in a biofilm modulate and intercept communication without direct interaction. Hence, the eradication of biofilms through hindering this communication will lead to the successful management of drug resistance and may be a novel target for antimicrobial chemotherapy. Chitosan shows microbicidal activities by acting electrostatically with its positively charged amino groups, which interact with anionic moieties on microbial species, causing enhanced membrane permeability and eventual cell death. Therefore, nanoparticles (NPs) prepared with chitosan possess a positive surface charge and mucoadhesive properties that can adhere to microbial mucus membranes and release their drug load in a constant release manner. As the success in therapeutics depends on the targeted delivery of drugs, chitosan nanomaterial, which displays low toxicity, can be safely used for eradicating a biofilm through attenuating the quorum sensing (QS). Since the anti-biofilm potential of chitosan and its nano-derivatives are reported for various microorganisms, these can be used as attractive tools for combating chronic infections and for the preparation of functionalized nanomaterials for different medical devices, such as orthodontic appliances. This mini-review focuses on the mechanism of the downregulation of quorum sensing using functionalized chitosan nanomaterials and the future prospects of its applications.
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26
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Namikawa H, Niki M, Niki M, Oinuma KI, Yamada K, Nakaie K, Tsubouchi T, Tochino Y, Takemoto Y, Kaneko Y, Kakeya H, Shuto T. Siderophore production as a biomarker for Klebsiella pneumoniae strains that cause sepsis: A pilot study. J Formos Med Assoc 2021; 121:848-855. [PMID: 34272150 DOI: 10.1016/j.jfma.2021.06.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 06/21/2021] [Accepted: 06/25/2021] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND/PURPOSE Klebsiella pneumoniae bacteremia-induced sepsis is a clinically important condition with a high mortality rate and various known virulence factors. However, studies on the association of these virulence factors with the occurrence of K. pneumoniae bacteremia-induced sepsis are scarce. We aimed to investigate clinical variables and virulence factors in patients with K. pneumoniae bacteremia-induced sepsis. METHODS We retrospectively reviewed the medical records of 76 patients with K. pneumoniae bacteremia between January 2012 and July 2017. Patients were divided into sepsis (n = 25) and non-sepsis (n = 51) groups. Patient background characteristics, antimicrobial regimens, and prognosis were evaluated. We assessed the distribution of virulence factors related to K. pneumoniae, such as mucoviscosity, capsular polysaccharide, and siderophores. Siderophore production levels were determined by measuring the orange halo zone on chrome azurol S agar plate assay. RESULTS There were no intergroup differences in male-to-female ratio and age. Multivariable analysis revealed that siderophore production level (p < 0.01) was an independent predictor of K. pneumoniae bacteremia-induced sepsis. Furthermore, the optimal cut-off point of siderophore production to predict sepsis was 9.6 mm (sensitivity, 86%; specificity, 76%; AUC, 0.81). CONCLUSION Siderophore production was an independent predictor of sepsis caused by K. pneumoniae bacteremia. The optimal cut-off point for siderophore production for sepsis occurrence prediction was 9.6 mm. To improve outcomes, patients with K. pneumoniae bacteremia-induced sepsis with high siderophore production levels should be managed prudently.
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Affiliation(s)
- Hiroki Namikawa
- Department of Medical Education and General Practice, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan.
| | - Makoto Niki
- Department of Infection Control and Prevention, Osaka City University Hospital, 1-5-7 Asahi-machi, Abeno-ku, Osaka, 545-8586, Japan
| | - Mamiko Niki
- Department of Bacteriology, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan; Research Center for Infectious Disease Sciences (RCIDS), Osaka City University Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Ken-Ichi Oinuma
- Department of Bacteriology, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan; Research Center for Infectious Disease Sciences (RCIDS), Osaka City University Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Koichi Yamada
- Department of Infection Control and Prevention, Osaka City University Hospital, 1-5-7 Asahi-machi, Abeno-ku, Osaka, 545-8586, Japan; Research Center for Infectious Disease Sciences (RCIDS), Osaka City University Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan; Department of Infection Control Science, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Kiyotaka Nakaie
- Department of Infection Control and Prevention, Osaka City University Hospital, 1-5-7 Asahi-machi, Abeno-ku, Osaka, 545-8586, Japan; Department of Infection Control Science, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Taishi Tsubouchi
- Department of Bacteriology, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan; Research Center for Infectious Disease Sciences (RCIDS), Osaka City University Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan; Toneyama Institute for Tuberculosis Research, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Yoshihiro Tochino
- Department of Medical Education and General Practice, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Yasuhiko Takemoto
- Department of Medical Education and General Practice, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Yukihiro Kaneko
- Department of Bacteriology, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan; Research Center for Infectious Disease Sciences (RCIDS), Osaka City University Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Hiroshi Kakeya
- Department of Infection Control and Prevention, Osaka City University Hospital, 1-5-7 Asahi-machi, Abeno-ku, Osaka, 545-8586, Japan; Research Center for Infectious Disease Sciences (RCIDS), Osaka City University Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan; Department of Infection Control Science, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
| | - Taichi Shuto
- Department of Medical Education and General Practice, Osaka City University, Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan
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27
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Khasheii B, Mahmoodi P, Mohammadzadeh A. Siderophores: Importance in bacterial pathogenesis and applications in medicine and industry. Microbiol Res 2021; 250:126790. [PMID: 34098495 DOI: 10.1016/j.micres.2021.126790] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 05/14/2021] [Accepted: 05/24/2021] [Indexed: 12/21/2022]
Abstract
Iron is an essential element for all microorganisms. Siderophores are low-weight, high-affinity iron chelating molecules produced in response to iron deficiency by Gram-positive and Gram-negative bacteria which also known as essential virulence factors of bacteria. Several studies have indicated that defective production and/or function of these molecules as well as iron acquisition systems in pathogens are associated with a reduction in pathogenicity of bacteria. Because of their potential role in various biological pathways, siderophores have been received special attention as secondary metabolites. Siderophores can detect iron levels in a variety of environments with a biosensor function. In medicine, siderophores are used to deliver antibiotics (Trojan horse strategy) to resistant bacteria and to treat diseases such as cancer and malaria. In this review, we discuss the iron acquisition pathways in Gram-positive and -negative bacteria, importance of siderophore production in pathogenesis of bacteria, classification of siderophores, and main applications of siderophores in medicine and industry.
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Affiliation(s)
- Behnoush Khasheii
- Department of Pathobiology, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran
| | - Pezhman Mahmoodi
- Department of Pathobiology, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran.
| | - Abdolmajid Mohammadzadeh
- Department of Pathobiology, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran
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28
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Klebba PE, Newton SMC, Six DA, Kumar A, Yang T, Nairn BL, Munger C, Chakravorty S. Iron Acquisition Systems of Gram-negative Bacterial Pathogens Define TonB-Dependent Pathways to Novel Antibiotics. Chem Rev 2021; 121:5193-5239. [PMID: 33724814 PMCID: PMC8687107 DOI: 10.1021/acs.chemrev.0c01005] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Iron is an indispensable metabolic cofactor in both pro- and eukaryotes, which engenders a natural competition for the metal between bacterial pathogens and their human or animal hosts. Bacteria secrete siderophores that extract Fe3+ from tissues, fluids, cells, and proteins; the ligand gated porins of the Gram-negative bacterial outer membrane actively acquire the resulting ferric siderophores, as well as other iron-containing molecules like heme. Conversely, eukaryotic hosts combat bacterial iron scavenging by sequestering Fe3+ in binding proteins and ferritin. The variety of iron uptake systems in Gram-negative bacterial pathogens illustrates a range of chemical and biochemical mechanisms that facilitate microbial pathogenesis. This document attempts to summarize and understand these processes, to guide discovery of immunological or chemical interventions that may thwart infectious disease.
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Affiliation(s)
- Phillip E Klebba
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Salete M C Newton
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - David A Six
- Venatorx Pharmaceuticals, Inc., 30 Spring Mill Drive, Malvern, Pennsylvania 19355, United States
| | - Ashish Kumar
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Taihao Yang
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Brittany L Nairn
- Department of Biological Sciences, Bethel University, 3900 Bethel Drive, St. Paul, Minnesota 55112, United States
| | - Colton Munger
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Somnath Chakravorty
- Jacobs School of Medicine and Biomedical Sciences, SUNY Buffalo, Buffalo, New York 14203, United States
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29
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Hu X, Cai Y, Wang Y, Wang R, Wang J, Zhang B. Imaging of bioluminescent Klebsiella pneumoniae induced pulmonary infection in an immunosuppressed mouse model. J Int Med Res 2020; 48:300060520956473. [PMID: 33044099 PMCID: PMC7556177 DOI: 10.1177/0300060520956473] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Objective To establish a mouse model of bioluminescent Klebsiella pneumoniae-induced lung infection, under different infection states after pretreatment with various dosages of cyclophosphamide (CTX). Methods A K. pneumoniae strain carrying the luxCDABE operon was used to infect immunocompetent mice (intraperitoneal injection of saline at 4 days and 1 day prior to experimental lung infection) and immunodeficient mice (50 mg/kg CTX at 4 days and 50 mg/kg CTX at 1 day prior to lung infection; or 150 mg/kg CTX at 4 days and 100 mg/kg CTX at 1 day prior to lung infection). Disease progression was monitored in living mice using a bioluminescence imaging system. The bioluminescent images, bacterial loads in lungs, blood cytological changes and histopathology of lungs were analysed. Results K. pneumoniae-induced lung infection models were established in mice pretreated with CTX. Different doses of CTX led to different severities of lung infection. Mice pretreated with 150/100 mg/kg CTX were more suitable for real-time monitoring as they had more typical bioluminescent images of lung infection, more obvious changes in the bioluminescent intensity values, more bacterial colonies in the lungs and more distinct pulmonary pathological changes. Conclusions A stable bioluminescent K. pneumonia-induced lung infection model was successfully established in mice pretreated with CTX, which can be semi-quantitatively monitored in real-time.
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Affiliation(s)
- Xing Hu
- Medical School of Chinese PLA, Beijing, China
| | - Yun Cai
- Medical School of Chinese PLA, Beijing, China.,Department of Pharmacy, Centre of Medicine Clinical Research, PLA General Hospital, Beijing, China
| | - Yuhang Wang
- Medical School of Chinese PLA, Beijing, China
| | - Rui Wang
- Department of Pharmacy, Centre of Medicine Clinical Research, PLA General Hospital, Beijing, China
| | - Jin Wang
- Department of Pharmacy, Centre of Medicine Clinical Research, PLA General Hospital, Beijing, China
| | - Bo Zhang
- Medical School of Chinese PLA, Beijing, China.,Department of Respiratory Medicine, Air Force General Hospital, PLA, Beijing, China
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30
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Wang G, Zhao G, Chao X, Xie L, Wang H. The Characteristic of Virulence, Biofilm and Antibiotic Resistance of Klebsiella pneumoniae. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17176278. [PMID: 32872324 PMCID: PMC7503635 DOI: 10.3390/ijerph17176278] [Citation(s) in RCA: 145] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 08/18/2020] [Accepted: 08/26/2020] [Indexed: 02/07/2023]
Abstract
Klebsiella pneumoniae is an important gram-negative opportunistic pathogen that causes a variety of infectious diseases, including urinary tract infections, bacteremia, pneumonia, and liver abscesses. With the emergence of multidrug-resistant (MDR) and hypervirulent K. pneumoniae (hvKP) strains, the rapid spread of these clinical strains in geography is particularly worrying. However, the detailed mechanisms of virulence and antibiotic resistance in K. pneumoniae are still not very clear. Therefore, studying and elucidating the pathogenic mechanisms and drug resistance mechanism of K. pneumoniae infection are important parts of current medical research. In this paper, we systematically summarized the virulence, biofilm, and antibiotic tolerance mechanisms of K. pneumoniae, and explored the application of whole genome sequencing and global proteomics, which will provide new clues for clinical treatment of K. pneumoniae.
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Affiliation(s)
| | | | | | - Longxiang Xie
- Correspondence: (L.X.); (H.W.); Tel.: +86-0371-22892960 (L.X.)
| | - Hongju Wang
- Correspondence: (L.X.); (H.W.); Tel.: +86-0371-22892960 (L.X.)
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31
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Structural and Functional Studies of a Klebsiella Phage Capsule Depolymerase Tailspike: Mechanistic Insights into Capsular Degradation. Structure 2020; 28:613-624.e4. [PMID: 32386574 DOI: 10.1016/j.str.2020.04.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 03/09/2020] [Accepted: 04/17/2020] [Indexed: 01/01/2023]
Abstract
Capsule polysaccharide is a major virulence factor of Klebsiella pneumoniae, a nosocomial pathogen associated with a wide range of infections. It protects bacteria from harsh environmental conditions, immune system response, and phage infection. To access cell wall-located receptors, some phages possess tailspike depolymerases that degrade the capsular polysaccharide. Here, we present the crystal structure of a tailspike against Klebsiella, KP32gp38, whose primary sequence shares no similarity to other proteins of known structure. In the trimeric structure of KP32gp38, each chain contains a flexible N-terminal domain, a right-handed parallel β helix domain and two β sandwiches with carbohydrate binding features. The crystal structure and activity assays allowed us to locate the catalytic site. Also, our data provide experimental evidence of a branching architecture of depolymerases in KP32 Klebsiella viruses, as KP32gp38 displays nanomolar affinity to another depolymerase from the same phage, KP32gp37. Results provide a structural framework for enzyme engineering to produce serotype-broad-active enzyme complexes against K. pneumoniae.
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32
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Choby JE, Howard-Anderson J, Weiss DS. Hypervirulent Klebsiella pneumoniae - clinical and molecular perspectives. J Intern Med 2020; 287:283-300. [PMID: 31677303 PMCID: PMC7057273 DOI: 10.1111/joim.13007] [Citation(s) in RCA: 244] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/24/2019] [Accepted: 10/01/2019] [Indexed: 12/29/2022]
Abstract
Hypervirulent Klebsiella pneumoniae (hvKp) has emerged as a concerning global pathogen. hvKp is more virulent than classical K. pneumoniae (cKp) and capable of causing community-acquired infections, often in healthy individuals. hvKp is carried in the gastrointestinal tract, which contributes to its spread in the community and healthcare settings. First recognized in Asia, hvKp arose as a leading cause of pyogenic liver abscesses. In the decades since, hvKp has spread globally and causes a variety of infections. In addition to liver abscesses, hvKp is distinct from cKp in its ability to metastasize to distant sites, including most commonly the eye, lung and central nervous system (CNS). hvKp has also been implicated in primary extrahepatic infections including bacteremia, pneumonia and soft tissue infections. The genetic determinants of hypervirulence are often found on large virulence plasmids as well as chromosomal mobile genetic elements which can be used as biomarkers to distinguish hvKp from cKp clinical isolates. These distinct virulence determinants of hvKp include up to four siderophore systems for iron acquisition, increased capsule production, K1 and K2 capsule types, and the colibactin toxin. Additionally, hvKp strains demonstrate hypermucoviscosity, a phenotypic description of hvKp in laboratory conditions that has become a distinguishing feature of many hypervirulent isolates. Alarmingly, multidrug-resistant hypervirulent strains have emerged, creating a new challenge in combating this already dangerous pathogen.
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Affiliation(s)
- J E Choby
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA.,Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA, USA.,Yerkes National Primate Research Center, Emory University School of Medicine, Atlanta, GA, USA
| | - J Howard-Anderson
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - D S Weiss
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA.,Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA, USA.,Yerkes National Primate Research Center, Emory University School of Medicine, Atlanta, GA, USA.,Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA.,Research Service, Atlanta VA Medical Center, Decatur, GA, USA
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33
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Chua MD, Bogdan AC, Guttman JA. Klebsiella pneumoniae Redistributes Katanin Severing Proteins and Alters Astral Microtubules during Mitosis. Anat Rec (Hoboken) 2019; 303:1859-1864. [PMID: 31595676 DOI: 10.1002/ar.24286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 07/31/2019] [Accepted: 08/28/2019] [Indexed: 11/09/2022]
Abstract
Klebsiella pneumoniae has become a growing concern within hospitals due to multidrug resistant strains and increasing mortality rates. Recently, we showed that at the subcellular level, K. pneumoniae compromises the integrity of the epithelia by disassembling the microtubule networks of cells through the actions of katanin microtubule severing proteins. In this study, we report on the observation that mitotic cells are targeted by K. pneumoniae and that during infections, the katanin proteins are excluded from the microtubule organizing centers of dividing cells, resulting in the alteration of the microtubule cytoskeleton. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1859-1864, 2020. © 2019 American Association for Anatomy.
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Affiliation(s)
- Michael D Chua
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Alexander C Bogdan
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Julian A Guttman
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
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34
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Contribution of Capsule to Virulence and Antibiotic Sensitivity of Klebsiella ozaenae Identified by Phenotypic and Molecular Methods. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2019. [DOI: 10.22207/jpam.13.3.50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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35
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Hamam SS, El Kholy RM, Zaki MES. Study of Various Virulence Genes, Biofilm Formation and Extended-Spectrum β-lactamase Resistance in Klebsiella pneumoniae Isolated from Urinary Tract Infections. Open Microbiol J 2019. [DOI: 10.2174/1874285801913010249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Objective:
The aims of the current study were to evaluate the capacity of K. pneumoniae isolated from hospital-acquired urinary tract infection to form biofilm, the relation of this capacity to various virulence genes and the prevalence of Extended Spectrum β-lactamases (ESBL) among these isolates by phenotypic and genotypic methods.
Material and Methods:
The study included 100 non-duplicate strains of K. pneumoniae isolated from 100 different urine samples from patients with hospital-acquired urinary tract infection. The isolated strains were studied for biofilm formation, ESBL production by phenotypic methods. Molecular studies were applied for the detection of ESβLs genes blaTEM, blaSHV, blaCTX-M and for detection of virulence genes fimH, uge, rmpA, mag A, wzy, kfa and aerobactin genes.
Result:
The majority of the isolates had the capacity to form a biofilm (81%), with ESBL prevalence rate 41%. The most prevalent gene among ESBL producing K. pneumoniae was blaCTX-M (73.2%) followed by blaSHV (53.6%) and blaTEM (51.2%). Among the virulence genes studied in K. pneumoniae isolates, the most prevalent gene was fimH (76%), uge (70%). There was significant association between ESBL production, and resistance to amikacin, cefepime, ceftazidime, gentamicin, imipenem and meropenem and biofilm production in K. pneumoniae isolates. There was significant association between blaCTX-M, blaSHV, fimH, mag, kfa, wzy, rmpA and aerobactin and biofilm production in K. pneumoniae.
Conclusion:
The present study highlights the prevalence of virulence genes among biofilm-forming strains of K. pneumoniae isolated from hospital-acquired urinary tract infection. Moreover, there was association between biofilm formation and ESBL production. Further studies are required to elucidate the clinical impact of the association of these different mechanisms.
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36
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Li G, Sun S, Zhao ZY, Sun Y. The pathogenicity of rmpA or aerobactin-positive Klebsiella pneumoniae in infected mice. J Int Med Res 2019; 47:4344-4352. [PMID: 31328596 PMCID: PMC6753543 DOI: 10.1177/0300060519863544] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Objectives To investigate the pathogenicity of Klebsiella
pneumoniae (KPN) possessing rmpA
or the aerobactin gene in infected mice. Methods BALB/c mice were divided into four groups (n = 10 per group) and
infected with: string test-positive and
rmpA-positive or aerobactin-positive KPN (group
1), string test-negative but rmpA-positive KPN
(group 2), string test-negative but aerobactin-positive KPN
(group 3), or string test- and
rmpA/aerobactin-negative KPN (group 4). Mouse
survival time was compared among groups, and the infection of
livers, spleens, lungs, and kidneys and KPN growth were assessed
in infected mice. Results Compared with the negative group (group 4), the survival rates of
mice infected with rmpA- or aerobactin-positive
KPN (groups 1–3) were significantly lower, their multi-organ
injuries were significantly more severe, and bacterial
enumeration was significantly higher. Conclusions Despite being string test-negative, aerobactin- or
rmpA-positive KPN still exhibit high
virulence and anti-immune effect activity. Therefore, the
combination of the string test and gene detection of aerobactin
and rmpA will be helpful in screening
hypervirulent KPN.
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Affiliation(s)
- Guili Li
- Department of Clinical Laboratory, Affiliated Hospital of Shandong Medical College, Shandong, China
| | - Shuhong Sun
- Department of Clinical Laboratory, Liny People's Hospital, Shandong, China
| | - Zhong Yuan Zhao
- Department of Clinical Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Yunfang Sun
- Department of Microbiology, Shandong Medical College, Linyi, Shandong, China
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Abstract
Hypervirulent K. pneumoniae (hvKp) is an evolving pathotype that is more virulent than classical K. pneumoniae (cKp). hvKp usually infects individuals from the community, who are often healthy. Infections are more common in the Asian Pacific Rim but are occurring globally. hvKp infection frequently presents at multiple sites or subsequently metastatically spreads, often requiring source control. hvKp has an increased ability to cause central nervous system infection and endophthalmitis, which require rapid recognition and site-specific treatment. The genetic factors that confer hvKp's hypervirulent phenotype are present on a large virulence plasmid and perhaps integrative conjugal elements. Increased capsule production and aerobactin production are established hvKp-specific virulence factors. Similar to cKp, hvKp strains are becoming increasingly resistant to antimicrobials via acquisition of mobile elements carrying resistance determinants, and new hvKp strains emerge when extensively drug-resistant cKp strains acquire hvKp-specific virulence determinants, resulting in nosocomial infection. Presently, clinical laboratories are unable to differentiate cKp from hvKp, but recently, several biomarkers and quantitative siderophore production have been shown to accurately predict hvKp strains, which could lead to the development of a diagnostic test for use by clinical laboratories for optimal patient care and for use in epidemiologic surveillance and research studies.
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Affiliation(s)
- Thomas A Russo
- Department of Medicine, University at Buffalo-State University of New York, Buffalo, New York, USA
- Department of Microbiology and Immunology, University at Buffalo-State University of New York, Buffalo, New York, USA
- The Witebsky Center for Microbial Pathogenesis, University at Buffalo-State University of New York, Buffalo, New York, USA
- The Veterans Administration Western New York Healthcare System, Buffalo, New York, USA
| | - Candace M Marr
- Department of Medicine, University at Buffalo-State University of New York, Buffalo, New York, USA
- Erie County Medical Center, Buffalo, New York, USA
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Caneiras C, Lito L, Melo-Cristino J, Duarte A. Community- and Hospital-Acquired Klebsiella pneumoniae Urinary Tract Infections in Portugal: Virulence and Antibiotic Resistance. Microorganisms 2019; 7:microorganisms7050138. [PMID: 31100810 PMCID: PMC6560439 DOI: 10.3390/microorganisms7050138] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/30/2019] [Accepted: 05/15/2019] [Indexed: 11/23/2022] Open
Abstract
Klebsiella pneumoniae is a clinically relevant pathogen and a frequent cause of hospital-acquired (HA) and community-acquired (CA) urinary tract infections (UTI). The increased resistance of this pathogen is leading to limited therapeutic options. To investigate the epidemiology, virulence, and antibiotic resistance profile of K. pneumoniae in urinary tract infections, we conducted a multicenter retrospective study for a total of 81 isolates (50 CA-UTI and 31 HA-UTI) in Portugal. The detection and characterization of resistance and virulence determinants were performed by molecular methods (PCR, PCR-based replicon typing, and multilocus sequence typing (MLST)). Out of 50 CA-UTI isolates, six (12.0%) carried β-lactamase enzymes, namely blaTEM-156 (n = 2), blaTEM-24 (n = 1), blaSHV-11 (n = 1), blaSHV-33 (n = 1), and blaCTX-M-15 (n = 1). All HA-UTI were extended-spectrum β-lactamase (ESBL) producers and had a multidrug resistant profile as compared to the CA-UTI isolates, which were mainly resistant to ciprofloxacin, levofloxacin, tigecycline, and fosfomycin. In conclusion, in contrast to community-acquired isolates, there is an overlap between virulence and multidrug resistance for hospital-acquired UTI K. pneumoniae pathogens. The study is the first to report different virulence characteristics for hospital and community K. pneumoniae pathogens, despite the production of β-lactamase and even with the presence of CTX-M-15 ESBL, a successful international ST15 clone, which were identified in both settings. This highlights that a focus on genomic surveillance should remain a priority in the hospital environment.
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Affiliation(s)
- Cátia Caneiras
- Microbiology and Immunology Department, Interdisciplinary Research Centre Egas Moniz (CiiEM), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal.
- Institute of Environmental Health (ISAMB), Faculty of Medicine, Universidade de Lisboa, 1649-028 Lisboa, Portugal.
| | - Luis Lito
- Laboratory of Microbiology, Centro Hospitalar Lisboa Norte, 1649-035 Lisboa, Portugal.
| | - José Melo-Cristino
- Laboratory of Microbiology, Centro Hospitalar Lisboa Norte, 1649-035 Lisboa, Portugal.
- Institute of Microbiology, Institute of Molecular Medicine, Faculty of Medicine, Universidade de Lisboa,1649-028 Lisboa, Portugal.
| | - Aida Duarte
- Microbiology and Immunology Department, Interdisciplinary Research Centre Egas Moniz (CiiEM), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal.
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Bengoechea JA, Sa Pessoa J. Klebsiella pneumoniae infection biology: living to counteract host defences. FEMS Microbiol Rev 2019; 43:123-144. [PMID: 30452654 PMCID: PMC6435446 DOI: 10.1093/femsre/fuy043] [Citation(s) in RCA: 256] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 11/16/2018] [Indexed: 12/26/2022] Open
Abstract
Klebsiella species cause a wide range of diseases including pneumonia, urinary tract infections (UTIs), bloodstream infections and sepsis. These infections are particularly a problem among neonates, elderly and immunocompromised individuals. Klebsiella is also responsible for a significant number of community-acquired infections. A defining feature of these infections is their morbidity and mortality, and the Klebsiella strains associated with them are considered hypervirulent. The increasing isolation of multidrug-resistant strains has significantly narrowed, or in some settings completely removed, the therapeutic options for the treatment of Klebsiella infections. Not surprisingly, this pathogen has then been singled out as an 'urgent threat to human health' by several organisations. This review summarises the tremendous progress that has been made to uncover the sophisticated immune evasion strategies of K. pneumoniae. The co-evolution of Klebsiella in response to the challenge of an activated immune has made Klebsiella a formidable pathogen exploiting stealth strategies and actively suppressing innate immune defences to overcome host responses to survive in the tissues. A better understanding of Klebsiella immune evasion strategies in the context of the host-pathogen interactions is pivotal to develop new therapeutics, which can be based on antagonising the anti-immune strategies of this pathogen.
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Affiliation(s)
- José A Bengoechea
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Joana Sa Pessoa
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast BT9 7BL, UK
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40
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Roe CC, Vazquez AJ, Esposito EP, Zarrilli R, Sahl JW. Diversity, Virulence, and Antimicrobial Resistance in Isolates From the Newly Emerging Klebsiella pneumoniae ST101 Lineage. Front Microbiol 2019; 10:542. [PMID: 31001209 PMCID: PMC6454207 DOI: 10.3389/fmicb.2019.00542] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 03/01/2019] [Indexed: 11/13/2022] Open
Abstract
The global dissemination of Klebsiella pneumoniae and Klebsiella pneumoniae carbapenemase (KPC) has been largely attributed to a few high-risk sequence types (STs) (ST258, ST11, ST512) associated with human disease. ST101 is an emerging clone that has been identified in different parts of the world with the potential to become a global, persistent public health threat. Recent research suggests the ST101 lineage is associated with an 11% increase in mortality rate in comparison to non-ST101 infections. In this study, we generated a high-quality, near-finished genome assembly of a multidrug-resistant (MDR) isolate from Italy (isolate 4743) that is a single locus variant of ST101 (ST1685). We demonstrate that the 4743 genome contains virulence features such as an integrative conjugative element carrying the yersiniabactin siderophore (ICEKp3), the mannose-resistant Klebsiella-like (type III) fimbriae cluster (mrkABCDFHIJ), the ferric uptake system (kfuABC), the yersiniabactin receptor gene fyuA, a capsular K type K17, and an O antigen type of O1. K. pneumoniae 4743 carries the blaKPC-2 carbapenemase gene along with genes conferring resistance to aminoglycosides, beta-lactams, fluoroquinolones, fosfomycin, macrolides, lincosamides, and streptogramin B. A comparative genomics analysis of 44 ST101 genomes as well as newly sequenced isolate 4743 identified variable antimicrobial resistance (AMR) resistance profiles and incompatibility plasmid types, but similar virulence factor profiles. Using Bayesian methodologies, we estimate the common ancestor for the ST101 lineage emerged in 1990 (95% HPD: 1965 to 2007) and isolates within the lineage acquired bla KPC after the divergence from its parental clonal group and dissemination. The identification of virulence factors and antibiotic resistance genes acquired by this newly emerging clone provides insight into the reported increased mortality rates and highlights its potential success as a persistent nosocomial pathogen. With a combination of both colistin resistance, carbapenem resistance, and several known virulence factors, the ST101 genetic repertoire may be a "perfect storm" allowing for a newly emerging, high-risk, extensively antibiotic resistant clone. This high-risk clone appears adept at acquiring resistance and may perpetuate the dissemination of extensive antimicrobial resistance. Greater focus on the acquisition of virulence factors and antibiotic resistance genes is crucial for understanding the spread of antibiotic resistance.
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Affiliation(s)
- Chandler C. Roe
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Adam J. Vazquez
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Eliana Pia Esposito
- Department of Public Health, University of Naples Federico II, Naples, Italy
| | - Raffaele Zarrilli
- Department of Public Health, University of Naples Federico II, Naples, Italy
| | - Jason W. Sahl
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
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Chakravorty S, Shipelskiy Y, Kumar A, Majumdar A, Yang T, Nairn BL, Newton SM, Klebba PE. Universal fluorescent sensors of high-affinity iron transport, applied to ESKAPE pathogens. J Biol Chem 2019; 294:4682-4692. [PMID: 30679312 DOI: 10.1074/jbc.ra118.006921] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/18/2019] [Indexed: 11/06/2022] Open
Abstract
Sensitive assays of biochemical specificity, affinity, and capacity are valuable both for basic research and drug discovery. We created fluorescent sensors that monitor high-affinity binding reactions and used them to study iron acquisition by ESKAPE bacteria, which are frequently responsible for antibiotic-resistant infections. By introducing site-directed Cys residues in bacterial iron transporters and modifying them with maleimide fluorophores, we generated living cells or purified proteins that bind but do not transport target compounds. These constructs sensitively detected ligand concentrations in solution, enabling accurate, real-time spectroscopic analysis of membrane transport by other cells. We assessed the efficacy of these "fluorescent decoy" (FD) sensors by characterizing active iron transport in the ESKAPE bacteria. The FD sensors monitored uptake of both ferric siderophores and hemin by the pathogens. An FD sensor for a particular ligand was universally effective in observing the uptake of that compound by all organisms we tested. We adapted the FD sensors to microtiter format, where they allow high-throughput screens for chemicals that block iron uptake, without genetic manipulations of the virulent target organisms. Hence, screening assays with FD sensors facilitate studies of mechanistic biochemistry, as well as discovery of chemicals that inhibit prokaryotic membrane transport. With appropriate design, FD sensors are potentially applicable to any pro- or eukaryotic high-affinity ligand transport process.
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Affiliation(s)
- Somnath Chakravorty
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Yan Shipelskiy
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Ashish Kumar
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Aritri Majumdar
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Taihao Yang
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Brittany L Nairn
- the Department of Biological Sciences, Bethel University, St. Paul, Minnesota 55112
| | - Salete M Newton
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
| | - Phillip E Klebba
- From the Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506 and
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Fu Y, Xu M, Liu Y, Li A, Zhou J. Virulence and genomic features of a bla CTX-M-3 and bla CTX-M-14 coharboring hypermucoviscous Klebsiella pneumoniae of serotype K2 and ST65. Infect Drug Resist 2019; 12:145-159. [PMID: 30655681 PMCID: PMC6322562 DOI: 10.2147/idr.s187289] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Background Capsular serotype K2 Klebsiella pneumoniae of sequence type (ST) 65 has been recognized as a hypervirulent clone. Simultaneous presence of different blaCTX-M genes has never been reported in this clone. In the present study, the genetic characteristics and virulence phenotype of a CTX-M-3 and CTX-M-14 coproducing ST65 K. pneumoniae human isolate, KP_06, that caused an intracranial infection, are evaluated. Methods The potential virulence of KP_06 was assayed by in vitro and in vivo methods. The molecular biology and whole-genome sequencing technology were used to analyze the genomic features associated with the virulence of this strain. Results The KP_06 exhibited typical features of hypervirulent K. pneumoniae (hvKP), showing hypermucoviscosity phenotype and belonging to K2 and ST65. Apart from virulence genes linked to hvKP, including rmpA, rmpA2, and clb cluster and genes encoding siderophores, it was found to harbor a ~170 kb pLVPK-like virulence plasmid. In contrast to most hvKP, KP_06 was resistant to cephalosporins and the coexistence of blaCTX-M-3 and blaCTX-M-14 was detected. Further experiments demonstrated that this strain was classified as a nonbiofilm producer and serum sensitivity (grade 1) and killed only 30% of Galleria mellonella inoculated with 1×106 colony-forming unit of the specimen within 48 hours, suggesting relatively low virulence. Comparative genomic analysis of KP_06 with five K2 hypermucoviscous K. pneumoniae (HMKP) revealed seven unique orthologies with varied function in this strain. Intriguingly, the virulence genes identified in KP-06 were unexpectedly more diverse than those observed in five other K2 HMKP strains. Conclusion Our data support the notion that neither virulence-associated genes (clusters) nor the pLVPK-like virulence plasmid is sufficient for the hypervirulence of K. pneumoniae. Future studies aiming to explore the virulence of K. pneumoniae should take genome-based profile together with experimental work. The detailed mechanism involving in the impaired virulence of KP_06 remains to be further explored.
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Affiliation(s)
- Yiqi Fu
- Department of Respiratory Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China,
| | - Min Xu
- Key Laboratory of Clinical In Vitro Diagnostic Techniques of Zhejiang Province, Center of Clinical Laboratory, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Yanchao Liu
- Key Laboratory of Clinical In Vitro Diagnostic Techniques of Zhejiang Province, Center of Clinical Laboratory, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Ang Li
- Department of Precision Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jianying Zhou
- Department of Respiratory Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China,
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Draft Whole-Genome Sequences of Seven Isolates of Klebsiella pneumoniae from New Zealand Sea Lions. Microbiol Resour Announc 2018; 7:MRA01270-18. [PMID: 30533818 PMCID: PMC6256617 DOI: 10.1128/mra.01270-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 10/22/2018] [Indexed: 01/12/2023] Open
Abstract
Klebsiella pneumoniae is a Gram-negative bacterium that may cause infection in a broad range of hosts. We report here the genome sequences of seven K. pneumoniae isolates from New Zealand sea lions. Klebsiella pneumoniae is a Gram-negative bacterium that may cause infection in a broad range of hosts. We report here the genome sequences of seven K. pneumoniae isolates from New Zealand sea lions.
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Dorman MJ, Feltwell T, Goulding DA, Parkhill J, Short FL. The Capsule Regulatory Network of Klebsiella pneumoniae Defined by density-TraDISort. mBio 2018; 9:e01863-18. [PMID: 30459193 PMCID: PMC6247091 DOI: 10.1128/mbio.01863-18] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 10/08/2018] [Indexed: 01/04/2023] Open
Abstract
Klebsiella pneumoniae infections affect infants and the immunocompromised, and the recent emergence of hypervirulent and multidrug-resistant K. pneumoniae lineages is a critical health care concern. Hypervirulence in K. pneumoniae is mediated by several factors, including the overproduction of extracellular capsule. However, the full details of how K. pneumoniae capsule biosynthesis is achieved or regulated are not known. We have developed a robust and sensitive procedure to identify genes influencing capsule production, density-TraDISort, which combines density gradient centrifugation with transposon insertion sequencing. We have used this method to explore capsule regulation in two clinically relevant Klebsiella strains, K. pneumoniae NTUH-K2044 (capsule type K1) and K. pneumoniae ATCC 43816 (capsule type K2). We identified multiple genes required for full capsule production in K. pneumoniae, as well as putative suppressors of capsule in NTUH-K2044, and have validated the results of our screen with targeted knockout mutants. Further investigation of several of the K. pneumoniae capsule regulators identified-ArgR, MprA/KvrB, SlyA/KvrA, and the Sap ABC transporter-revealed effects on capsule amount and architecture, serum resistance, and virulence. We show that capsule production in K. pneumoniae is at the center of a complex regulatory network involving multiple global regulators and environmental cues and that the majority of capsule regulatory genes are located in the core genome. Overall, our findings expand our understanding of how capsule is regulated in this medically important pathogen and provide a technology that can be easily implemented to study capsule regulation in other bacterial species.IMPORTANCE Capsule production is essential for K. pneumoniae to cause infections, but its regulation and mechanism of synthesis are not fully understood in this organism. We have developed and applied a new method for genome-wide identification of capsule regulators. Using this method, many genes that positively or negatively affect capsule production in K. pneumoniae were identified, and we use these data to propose an integrated model for capsule regulation in this species. Several of the genes and biological processes identified have not previously been linked to capsule synthesis. We also show that the methods presented here can be applied to other species of capsulated bacteria, providing the opportunity to explore and compare capsule regulatory networks in other bacterial strains and species.
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Affiliation(s)
- Matthew J Dorman
- Wellcome Sanger Institute, Hinxton, Cambridgeshire, United Kingdom
| | - Theresa Feltwell
- Wellcome Sanger Institute, Hinxton, Cambridgeshire, United Kingdom
| | - David A Goulding
- Wellcome Sanger Institute, Hinxton, Cambridgeshire, United Kingdom
| | - Julian Parkhill
- Wellcome Sanger Institute, Hinxton, Cambridgeshire, United Kingdom
| | - Francesca L Short
- Wellcome Sanger Institute, Hinxton, Cambridgeshire, United Kingdom
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
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Wang X, Xie Y, Li G, Liu J, Li X, Tian L, Sun J, Ou HY, Qu H. Whole-Genome-Sequencing characterization of bloodstream infection-causing hypervirulent Klebsiella pneumoniae of capsular serotype K2 and ST374. Virulence 2018; 9:510-521. [PMID: 29338592 PMCID: PMC5955473 DOI: 10.1080/21505594.2017.1421894] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Hypervirulent K. pneumoniae variants (hvKP) have been increasingly reported worldwide, causing metastasis of severe infections such as liver abscesses and bacteremia. The capsular serotype K2 hvKP strains show diverse multi-locus sequence types (MLSTs), but with limited genetics and virulence information. In this study, we report a hypermucoviscous K. pneumoniae strain, RJF293, isolated from a human bloodstream sample in a Chinese hospital. It caused a metastatic infection and fatal septic shock in a critical patient. The microbiological features and genetic background were investigated with multiple approaches. The Strain RJF293 was determined to be multilocis sequence type (ST) 374 and serotype K2, displayed a median lethal dose (LD50) of 1.5 × 102 CFU in BALB/c mice and was as virulent as the ST23 K1 serotype hvKP strain NTUH-K2044 in a mouse lethality assay. Whole genome sequencing revealed that the RJF293 genome codes for 32 putative virulence factors and exhibits a unique presence/absence pattern in comparison to the other 105 completely sequenced K. pneumoniae genomes. Whole genome SNP-based phylogenetic analysis revealed that strain RJF293 formed a single clade, distant from those containing either ST66 or ST86 hvKP. Compared to the other sequenced hvKP chromosomes, RJF293 contains several strain-variable regions, including one prophage, one ICEKp1 family integrative and conjugative element and six large genomic islands. The sequencing of the first complete genome of an ST374 K2 hvKP clinical strain should reinforce our understanding of the epidemiology and virulence mechanisms of this bloodstream infection-causing hvKP with clinical significance.
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Affiliation(s)
- Xiaoli Wang
- a Department of Critical Care Medicine , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Yingzhou Xie
- b State Key Laboratory of Microbial Metabolism , Joint International Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University , Shanghai , China
| | - Gang Li
- c Department of Laboratory Medicine , Jinshan Hospital, Shanghai Medical College, Fudan University , Shanghai , China.,d Department of Laboratory Medicine , Huashan Hospital, Shanghai Medical College, Fudan University , Shanghai , China
| | - Jialin Liu
- a Department of Critical Care Medicine , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Xiaobin Li
- b State Key Laboratory of Microbial Metabolism , Joint International Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University , Shanghai , China
| | - Lijun Tian
- a Department of Critical Care Medicine , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Jingyong Sun
- e Department of Clinical Microbiology , Ruijin Hospital, Shanghai Jiaotong University School of Medicine , Shanghai , China
| | - Hong-Yu Ou
- b State Key Laboratory of Microbial Metabolism , Joint International Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University , Shanghai , China
| | - Hongping Qu
- a Department of Critical Care Medicine , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
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Identification of Biomarkers for Differentiation of Hypervirulent Klebsiella pneumoniae from Classical K. pneumoniae. J Clin Microbiol 2018; 56:JCM.00776-18. [PMID: 29925642 DOI: 10.1128/jcm.00776-18] [Citation(s) in RCA: 341] [Impact Index Per Article: 56.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 06/12/2018] [Indexed: 12/25/2022] Open
Abstract
A hypervirulent Klebsiella pneumoniae (hvKp) pathotype is undergoing global dissemination. In contrast to the usual health care-associated epidemiology of classical K. pneumoniae (cKp) infections, hvKp causes tissue-invasive infections in otherwise healthy individuals from the community, often involving multiple sites. An accurate test to identify hvKp strains is needed for improved patient care and epidemiologic studies. To fill this knowledge gap, clinical criteria or random blood isolates from North American and United Kingdom strain collections were used to assemble hvKp-rich (n = 85) and cKp-rich (n = 90) strain cohorts, respectively. The isolates were then assessed for multiple candidate biomarkers hypothesized to accurately differentiate the two cohorts. The genes peg-344, iroB, iucA, plasmid-borne rmpA gene ( prmpA), and prmpA2 all demonstrated >0.95 diagnostic accuracy for identifying strains in the hvKp-rich cohort. Next, to validate this epidemiological analysis, all strains were assessed experimentally in a murine sepsis model. peg-344, iroB, iucA, prmpA, and prmpA2 were all associated with a hazard ratio of >25 for severe illness or death, additionally supporting their utility for identifying hvKp strains. Quantitative siderophore production of ≥30 μg/ml also strongly predicted strains as members of the hvKp-rich cohort (accuracy, 0.96) and exhibited a hazard ratio of 31.7 for severe illness or death. The string test, a widely used marker for hvKp strains, performed less well, achieving an accuracy of only 0.90. Last, using the most accurate biomarkers to define hvKp, prevalence studies were performed on two Western strain collections. These data strongly support the utility of several laboratory markers for identifying hvKp strains with a high degree of accuracy.
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Dickson K, Liu S, Zhou J, Langille M, Holbein BE, Lehmann C. Selective sensitivity of the gut microbiome to iron chelators in polybacterial abdominal sepsis. Med Hypotheses 2018; 120:68-71. [PMID: 30220344 DOI: 10.1016/j.mehy.2018.08.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 07/16/2018] [Accepted: 08/23/2018] [Indexed: 01/09/2023]
Abstract
Iron chelation has been proposed as a potential therapy for polybacterial abdominal sepsis. Treatment with iron chelation is known to be able to attenuate bacterial growth. It is hypothesized that the different types of bacteria will exhibit variations in their sensitivity to iron chelation based on differences in their iron metabolism. Bacteria with weaker iron access systems might have their growth reduced initially, but stronger species may also be suppressed. Gram-positive and Gram-negative bacteria are known to possess different iron acquisition systems, which may affect their response to iron chelation. Bacteria which can produce siderophores are at a particular advantage for iron acquisition. Novel iron chelators, which do not act as xenosiderophores, may be effective in depriving these bacteria of iron. This has implications for the treatment of polybacterial sepsis, which might be enhanced if the sensitivity to iron chelation of the primary causative agents is known.
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Affiliation(s)
- Kayle Dickson
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada
| | - Simo Liu
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada
| | - Juan Zhou
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada
| | - Morgan Langille
- Department of Pharmacology, Dalhousie University, Halifax, Canada
| | - Bruce E Holbein
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Canada
| | - Christian Lehmann
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada; Department of Pharmacology, Dalhousie University, Halifax, Canada; Department of Microbiology and Immunology, Dalhousie University, Halifax, Canada.
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Rafat C, Messika J, Barnaud G, Dufour N, Magdoud F, Billard-Pomarès T, Gaudry S, Dreyfuss D, Branger C, Decré D, Ricard JD. Hypervirulent Klebsiella pneumoniae, a 5-year study in a French ICU. J Med Microbiol 2018; 67:1083-1089. [PMID: 29972348 DOI: 10.1099/jmm.0.000788] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
PURPOSE Hypervirulent Klebsiella pneumoniae (hvKp) has emerged as a leading cause of severe community-acquired pneumonia, liver abscess and disseminated infection in the Far East. Data regarding the incidence, clinical features and microbiological characteristics related to hvKp infections in the Western world are scarce. METHODOLOGY The incidence, clinical features and microbiological characteristics of hvKp infections were investigated through a 5-year survey conducted in a single French intensive care unit. K. pneumoniae strains were screened for hypermucoviscosity based on a string test. Multilocus sequence typing and multiplex PCR analysis targeting virulence genes were performed on string test-positive strains. RESULTS Over a 53-month period, a total of 59 infections due to K. pneumoniae were identified including 26 community-onset infections. Twelve hvKp infections were documented, accounting for 46.1 % of community-acquired K. pneumoniae. Community-acquired pneumonia (n=6), aspiration pneumonia (n=4) and liver abscess (n=2) represented initial sites and mode of infection. Compared to non-hvKp infections, patients with hvKp infections displayed higher rates of multi-organ failure (83.3 % vs 35.7 %; P=0.04), but mortality rates were not different (50 % vs 35 %; P=0.71). Strains K1/ST23 (n=5) and K2/ST86 (n=5) predominated. All hvKp strains displayed wild-type susceptibility. CONCLUSION hvKp represent a potentially underestimated cause of fatal infections in the Western world.
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Affiliation(s)
- Cédric Rafat
- 2Urgences Néphrologiques et Transplantation Rénale, Groupe hospitalier des Hôpitaux Universitaires de l'Est Parisien, Hôpital Tenon, Assistance Publique-Hôpitaux de Paris, Paris, France
- 1Service de Réanimation Médico-Chirurgicale, Hôpital Louis Mourier Assistance Publique-Hôpitaux de Paris, Colombes, France
| | - Jonathan Messika
- 1Service de Réanimation Médico-Chirurgicale, Hôpital Louis Mourier Assistance Publique-Hôpitaux de Paris, Colombes, France
- 3INSERM, IAME, UMR 1137, F-75018 Paris, France
- 4Univ Paris Diderot, IAME, UMR 1137, Sorbonne Paris Cité, F-75018 Paris, France
| | - Guilène Barnaud
- 5Service de Microbiologie, Hôpital Louis Mourier, Assistance Publique-Hôpitaux de Paris, Colombes, France
| | - Nicolas Dufour
- 1Service de Réanimation Médico-Chirurgicale, Hôpital Louis Mourier Assistance Publique-Hôpitaux de Paris, Colombes, France
- 6Service de Réanimation médico-chirurgicale, Centre Hospitalier René Dubos, F-95300 Pontoise, France
| | - Fatma Magdoud
- 5Service de Microbiologie, Hôpital Louis Mourier, Assistance Publique-Hôpitaux de Paris, Colombes, France
| | - Typhaine Billard-Pomarès
- 3INSERM, IAME, UMR 1137, F-75018 Paris, France
- 4Univ Paris Diderot, IAME, UMR 1137, Sorbonne Paris Cité, F-75018 Paris, France
- 5Service de Microbiologie, Hôpital Louis Mourier, Assistance Publique-Hôpitaux de Paris, Colombes, France
| | - Stéphane Gaudry
- 1Service de Réanimation Médico-Chirurgicale, Hôpital Louis Mourier Assistance Publique-Hôpitaux de Paris, Colombes, France
- 7Univ Paris Diderot, Sorbonne Paris Cité, ECEVE, UMRS 1123, F-75010 Paris, France
- 8INSERM, ECEVE, U1123, CIC-EC 1425, F-75010 Paris, France
| | - Didier Dreyfuss
- 1Service de Réanimation Médico-Chirurgicale, Hôpital Louis Mourier Assistance Publique-Hôpitaux de Paris, Colombes, France
- 3INSERM, IAME, UMR 1137, F-75018 Paris, France
- 4Univ Paris Diderot, IAME, UMR 1137, Sorbonne Paris Cité, F-75018 Paris, France
| | - Catherine Branger
- 3INSERM, IAME, UMR 1137, F-75018 Paris, France
- 4Univ Paris Diderot, IAME, UMR 1137, Sorbonne Paris Cité, F-75018 Paris, France
- 5Service de Microbiologie, Hôpital Louis Mourier, Assistance Publique-Hôpitaux de Paris, Colombes, France
| | - Dominique Decré
- 9Sorbonne Université, Paris 06, INSERM, U1135, Centre d'Immunologie et des Maladies Infectieuses (Cimi-Paris), Team E13 (Bacteriology), Paris, France
- 10AP-HP, Microbiology, St-Antoine Hospital, Paris, France
| | - Jean-Damien Ricard
- 1Service de Réanimation Médico-Chirurgicale, Hôpital Louis Mourier Assistance Publique-Hôpitaux de Paris, Colombes, France
- 3INSERM, IAME, UMR 1137, F-75018 Paris, France
- 4Univ Paris Diderot, IAME, UMR 1137, Sorbonne Paris Cité, F-75018 Paris, France
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Selection and validation of reference genes for gene expression studies in Klebsiella pneumoniae using Reverse Transcription Quantitative real-time PCR. Sci Rep 2018; 8:9001. [PMID: 29899556 PMCID: PMC5998039 DOI: 10.1038/s41598-018-27420-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 05/23/2018] [Indexed: 12/27/2022] Open
Abstract
For reliable results, Reverse Transcription Quantitative real-time Polymerase Chain Reaction (RT-qPCR) analyses depend on stably expressed reference genes for data normalization purposes. Klebsiella pneumoniae is an opportunistic Gram-negative bacterium that has become a serious threat worldwide. Unfortunately, there is no consensus for an ideal reference gene for RT-qPCR data normalization on K. pneumoniae. In this study, the expression profile of eleven candidate reference genes was assessed in K. pneumoniae cells submitted to various experimental conditions, and the expression stability of these candidate genes was evaluated using statistical algorithms BestKeeper, NormFinder, geNorm, Delta CT and RefFinder. The statistical analyses ranked recA, rho, proC and rpoD as the most suitable reference genes for accurate RT-qPCR data normalization in K. pneumoniae. The reliability of the proposed reference genes was validated by normalizing the relative expression of iron-regulated genes in K. pneumoniae cells submitted to iron-replete and iron-limited conditions. This work emphasizes that the stable expression of any potential reference candidate gene must be validated in each physiological condition or experimental treatment under study.
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50
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Zha H, Jeffs A, Dong Y, Lewis G. Potential virulence factors of bacteria associated with tail fan necrosis in the spiny lobster, Jasus edwardsii. JOURNAL OF FISH DISEASES 2018; 41:817-828. [PMID: 29473647 DOI: 10.1111/jfd.12791] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 01/05/2018] [Accepted: 01/08/2018] [Indexed: 06/08/2023]
Abstract
Tail fan necrosis (TFN) is a common condition found in commercially exploited spiny lobsters that greatly diminishes their commercial value. Bacteria possessing proteolytic, chitinolytic and lipolytic capabilities were associated with TFN in spiny lobsters, Jasus edwardsii. In this study, 69 bacterial isolates exhibiting all the three enzymatic capabilities from the haemolymph and tail fans of J. edwardsii with and without TFN were further characterized and compared, including morphology, biofilm formation, antimicrobial activity, antimicrobial resistance, and production of siderophores, melanin and ammonia. The genomic patterns of the most common Vibrio crassostreae isolates were also compared between TFN-affected and unaffected lobsters. Biofilm formation was stronger in bacterial isolates from both haemolymph and tail fans of TFN-affected lobsters compared to those from the unaffected lobsters, while melanin production and siderophore production were stronger in the isolates from tail fans of lobsters with TFN. By contrast, the other characteristics of isolates were similar in lobsters with and without TFN. The Vib. crassostreae isolates from the affected lobsters had similar genomic patterns. Overall, the results indicate that in addition to proteolytic, chitinolytic and lipolytic activities, the bacteria associated with TFN commonly have enhanced activity of important virulence factors, including biofilm formation, melanin production and siderophore production.
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Affiliation(s)
- H Zha
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
- Institute of Marine Science, University of Auckland, Auckland, New Zealand
| | - A Jeffs
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
- Institute of Marine Science, University of Auckland, Auckland, New Zealand
| | - Y Dong
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - G Lewis
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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