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Alshiekheid MA, Dou AM, Algahtani M, Al-Megrin WAI, Alhawday YA, Alradhi AE, Bukhari K, Alharbi BF, Algefary AN, Alhunayhani BA, Allemailem KS. Bioinformatics and immunoinformatics assisted multiepitope vaccine construct against Burkholderia anthina. Saudi Pharm J 2024; 32:101917. [PMID: 38226347 PMCID: PMC10788630 DOI: 10.1016/j.jsps.2023.101917] [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: 08/30/2023] [Accepted: 12/11/2023] [Indexed: 01/17/2024] Open
Abstract
Burkholderia anthina is a pathogenic bacterial species belonging to the Burkholderiaceae family and it is mainly considered the etiological agent of chronic obstructive pulmonary diseases associated with cystic fibrosis, due to being intrinsic antibiotic resistant making it difficult to treat pulmonary infections. Hence increased rate of antibiotic-resistant bacterial species vaccine development is the priority to tackle this problem. In research work, we designed a multi-epitope-based vaccine construct against B. anthina using reverse vaccinology immunoinformatics and biophysical approaches. Based on the subtractive proteomic screening of core proteins we identified 3 probable antigenic proteins and good vaccine targets namely, type VI secretion system tube protein hcp Burkholderia, fimbria/pilus periplasmic chaperone and fimbrial biogenesis outer membrane usher protein. The selected 3 proteins were used for B and B cells B-derived T-cell epitopes prediction. In epitopes prediction, different epitopes were predicted with various lengths and percentile scores and subjected to further immunoinformatics analysis. In immunoinformatics screening a total number of 06, IDDGNANAL, KTVKPDPRY, SEVESGSAP, YGGDLTVEV, SVSHDTNGR, and GSKADGYQR epitopes were considered good vaccine target candidates and shortlisted for vaccine construct designing. The vaccine construct was designed by joining selected epitopes with the help of a GPGPG linker and additionally linked with cholera toxin b subunit adjuvant to increase the efficacy of the vaccine construct the sequence of the said adjuvant were retrieved from protein data bank through its (PDB ID: 5ELD). The designed vaccine construct was evaluated for its physiochemical properties analysis in which we reported that the vaccine construct comprises 216 amino acids with a molecular weight of 22.37499 kilo Dalton, 15.55 instability index (II) is computed, and this classifies that the vaccine construct is properly stable. VaxiJen v2.0 web server predicted that the vaccine construct is probable antigenic in nature with 0.6320 predicted value. Furthermore AllerTOP v. 2.0 tool predicted that the designed vaccine construct is non allergic in nature. Molecular docking analysis was done for analysis of the binding affinity of the vaccine construct with TLR-2 (PDB ID: 6NIG), the docking results predicted 799.2 kcal/mol binding energy score that represents the vaccine construct has a good binding ability with TLR-2. Moreover, molecular dynamic simulation analysis results revealed that the vaccine construct and immune cell receptor has proper binding stability over various environmental condition, i.e. change in pressure range, temperature, and motion. After each analysis, we observed that the vaccine construct is safe stable, and probably antigenic and could generate an immune response against the target pathogen but in the future, experimental analysis is still needed to verify in silico base results.
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Affiliation(s)
- Maha A. Alshiekheid
- Department of Botany & Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ali M. Dou
- Department of Medical Laboratories, Riyadh Security Forces Hospital, Ministry of Interior, Riyadh 11481, Saudi Arabia
| | - Mohammad Algahtani
- Department of Laboratory & Blood Bank, Security Forces Hospital, P.O. Box 14799, Mecca 21955, Saudi Arabia
| | - Wafa Abdullah I. Al-Megrin
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Yaseer Ali Alhawday
- Department of Medical Microbiology, Qassim University Medical City , Qassim University, Buraydah 51452, Saudi Arabia
| | - Arwa Essa Alradhi
- Regional Laboratory and Central Blood Bank, Hafr Al Batin 39513, Saudi Arabia
| | - Khulud Bukhari
- Department of Microbiology and Parasitology, College of Veterinary Medicine, P. O. Box 1757, Hofuf 36388, Al-Ahsa, King Faisal University, Saudi Arabia
| | - Basmah F. Alharbi
- Department of Basic Health Science, College of Applied Medical Sciences, Qassim University, Buraydah 51452, Saudi Arabia
| | - Ahmed N. Algefary
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah 51452, Saudi Arabia
| | - Basmah Awwadh Alhunayhani
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah 51452, Saudi Arabia
| | - Khaled S. Allemailem
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah 51452, Saudi Arabia
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Beca FA, Sengillo JD, Robles-Holmes HK, Iyer PG, Miller D, Yannuzzi NA, Flynn HW. Endophthalmitis caused by Burkholderia cepacia complex (BCC): clinical characteristics, antibiotic susceptibilities, and treatment outcomes. J Ophthalmic Inflamm Infect 2023; 13:48. [PMID: 37922028 PMCID: PMC10624773 DOI: 10.1186/s12348-023-00370-1] [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: 07/18/2023] [Accepted: 10/15/2023] [Indexed: 11/05/2023] Open
Abstract
PURPOSE To report the clinical characteristics, antibiotic susceptibilities, and review the literature of Burkholderia cepacia complex (BCC) associated endophthalmitis. STUDY DESIGN Retrospective, observational case series. METHODS Clinical and microbiology records were reviewed for patients evaluated at the Bascom Palmer Eye Institute and diagnosed wisth culture-confirmed endophthalmitis due to BCC. Antibiotic susceptibility profiles were generated using standard microbiologic protocols via an automated VITEK system. RESULTS Endophthalmitis associated with BCC was diagnosed in three patients. Infection occurred in the setting of post-penetrating keratoplasty (PKP), glaucoma filtering surgery, and suspected trauma. All isolates demonstrated in vitro susceptibility to ceftazidime and meropenem. Presenting visual acuity (VA) ranged from hand motion to light perception. Initial treatment strategies included intravitreal ceftazidime (2.25 mg/0.1 mL) and vancomycin (1.0 mg/0.1 mL) injections with fortified topical antibiotics in 2 patients, and surgical debridement of a corneoscleral melt with patch graft along with both topical fortified antibiotics oral antibiotics in the third patient. In all 3 patients, there was no VA improvement at last follow-up, as 2 eyes ultimately underwent enucleation and 1 eye exhibited phthisis bulbi at last follow-up. BCC related endophthalmitis was reviewed among 13 reports. Treatment outcomes were generally poor and antibiotic resistance was common. These BCC isolates cases demonstrated broad resistance patterns, with susceptibilities to ceftazidime (58%), ciprofloxacin (53%), and gentamicin (33%). CONCLUSIONS Endophthalmitis caused by B. cepacia is a rare clinical entity with generally poor visual outcomes despite prompt treatment with appropriate antibiotics.
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Affiliation(s)
- Flavius A Beca
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jesse D Sengillo
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Hailey K Robles-Holmes
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Prashanth G Iyer
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Darlene Miller
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Nicolas A Yannuzzi
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Harry W Flynn
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA.
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3
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Beca FA, Sengillo JD, Robles-Holmes HK, Iyer PG, Miller D, Yannuzzi NA, Flynn HW. Endophthalmitis caused by Burkholderia cepacia complex (BCC): Clinical characteristics, antibiotic susceptibilities, and treatment outcomes. RESEARCH SQUARE 2023:rs.3.rs-3181158. [PMID: 37503162 PMCID: PMC10371171 DOI: 10.21203/rs.3.rs-3181158/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Purpose To report the clinical characteristics, antibiotic susceptibilities, and review the literature of Burkholderia cepacia complex (BCC) associated endophthalmitis. Study design Retrospective, observational case series. Methods Clinical and microbiology records were reviewed for patients evaluated at the Bascom Palmer Eye Institute and diagnosed with culture-confirmed endophthalmitis due to BCC. Antibiotic susceptibility profiles were generated using standard microbiologic protocols via an automated VITEK system. Results Endophthalmitis associated with BCC was diagnosed in three patients. Infection occurred in the setting of post-penetrating keratoplasty (PKP), glaucoma filtering surgery, and suspected trauma. All isolates demonstrated in vitro susceptibility to ceftazidime and meropenem. Presenting visual acuity (VA) ranged from hand motion to light perception. Initial treatment strategies included intravitreal ceftazidime (2.25 mg/0.1 mL) and vancomycin (1.0 mg/0.1mL) injections with fortified topical antibiotics in 2 patients, and surgical debridement of a corneoscleral melt with patch graft along with both topical fortified antibiotics oral antibiotics in the third patient. In all 3 patients, there was no VA improvement at last follow-up, as 2 eyes ultimately underwent enucleation and 1 eye exhibited phthisis bulbi at last follow-up. BCC related endophthalmitis was reviewed among 13 reports. Treatment outcomes were generally poor and antibiotic resistance was common. These BCC isolates cases demonstrated broad resistance patterns, with susceptibilities to ceftazidime (58%), ciprofloxacin (53%), and gentamicin (33%). Conclusions Endophthalmitis caused by B. cepacia is a rare clinical entity with generally poor visual outcomes despite prompt treatment with appropriate antibiotics.
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Batista MPB, Cavalcante FS, Alves Cassini ST, Pinto Schuenck R. Diversity of bacteria carrying antibiotic resistance genes in hospital raw sewage in Southeastern Brazil. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 87:239-250. [PMID: 36640035 DOI: 10.2166/wst.2022.427] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In recent decades, antibiotic-resistant bacteria (ARB) emerged and spread among humans and animals worldwide. In this study, we evaluated the presence of ARB and antibiotic resistance genes (ARGs) in the raw sewage of two hospitals in Brazil. Sewage aliquots were inoculated in a selective medium with antibiotics. Bacterial identification was performed by MALDI-TOF and ARGs were assessed by polymerase chain reaction (PCR). A total of 208 strains from both hospitals were isolated (H1 = 117; H2 = 91). A wide variety of Enterobacterales and non-Enterobacterales species were isolated and most of them were Enterobacter spp. (13.0%), Proteus mirabilis (10.1%), and Klebsiella pneumoniae (9.6%). blaTEM and blaKPC were the most frequent β-lactamase-encoding genes and the predominant macrolide resistance genes were mph(A) and mel. Many species had the three tetracycline resistance genes (tetD, tetM, tetA) and strB was the prevalent aminoglycoside resistance gene. Two Staphylococcus haemolyticus strains had the mecA gene. Quinolone, colistin, and vancomycin resistance genes were not found. This study showed that hospital raw sewage is a great ARB and ARG disseminator. Strict monitoring of hospital sewage treatment is needed to avoid the spread of these genes among bacteria in the environment.
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Affiliation(s)
| | | | | | - Ricardo Pinto Schuenck
- Department of Pathology, Health Sciences Center, Federal University of Espírito Santo, Vitória, Brazil E-mail:
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McAvoy AC, Threatt PH, Kapcia J, Garg N. Discovery of Homogentisic Acid as a Precursor in Trimethoprim Metabolism and Natural Product Biosynthesis. ACS Chem Biol 2022; 18:711-723. [PMID: 36215670 DOI: 10.1021/acschembio.2c00529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Opportunistic infections by Burkholderia cenocepacia are life threatening for patients suffering from cystic fibrosis and chronic granulomatous disease. These infections are often associated with variable clinical outcomes, prompting an interest in molecular investigations of phenotypes associated with disease severity. The production of the pyomelanin pigment is one such phenotype, which was recently linked to the ability of clinical strains to carry out biotransformation of the antibiotic trimethoprim. However, this biotransformation product was not identified, and differences in metabolite production associated with pyomelanin pigmentation are poorly understood. Here, we identify several key metabolites produced exclusively by the pyomelanin-producing strains. To provide insight into the structures and biosynthetic origin of these metabolites, we developed a mass spectrometry-based strategy coupling unsupervised in silico substructure prediction with stable isotope labeling referred to as MAS-SILAC (Metabolite Annotation assisted by Substructure discovery and Stable Isotope Labeling by Amino acids in Cell culture). This approach led to discovery of homogentisic acid as a precursor for biosynthesis of several natural products and for biotransformation of trimethoprim, representing a previously unknown mechanism of antibiotic tolerance. This work presents application of computational methods for analysis of untargeted metabolomic data to link the chemotype of pathogenic microorganisms with a specific phenotype. The observations made in this study provide insights into the clinical significance of the melanated phenotype.
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Affiliation(s)
- Andrew C McAvoy
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Drive, Atlanta, Georgia 30332-2000, United States
| | - Paxton H Threatt
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Drive, Atlanta, Georgia 30332-2000, United States
| | - Joseph Kapcia
- Department of Molecular Biology and Biochemistry, University of California, Irvine, 3205 McGaugh Hall, Irvine, California 92697-2525, United States
| | - Neha Garg
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Drive, Atlanta, Georgia 30332-2000, United States.,Center for Microbial Dynamics and Infection, Georgia Institute of Technology, 311 Ferst Drive, ES&T, Atlanta, Georgia 30332, United States
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Identification of Key Factors for Anoxic Survival of B. cenocepacia H111. Int J Mol Sci 2022; 23:ijms23094560. [PMID: 35562951 PMCID: PMC9104464 DOI: 10.3390/ijms23094560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 04/11/2022] [Accepted: 04/15/2022] [Indexed: 11/21/2022] Open
Abstract
Burkholderia cenocepacia is an opportunistic pathogen that can lead to severe infections in patients suffering from cystic fibrosis (CF) and chronic granulomatous disease. Being an obligate aerobe, B. cenocepacia is unable to grow in the absence of oxygen. In this study, we show that the CF isolate B. cenocepacia H111 can survive in the absence of oxygen. Using a transposon sequencing (Tn-seq) approach, we identified 71 fitness determinants involved in anoxic survival, including a Crp-Fnr family transcriptional regulatory gene (anr2), genes coding for the sensor kinase RoxS and its response regulator RoxR, the sigma factor for flagella biosynthesis (FliA) and subunits of a cytochrome bd oxidase (CydA, CydB and the potentially novel subunit CydP). Individual knockouts of these fitness determinants significantly reduced anoxic survival, and inactivation of both anr copies is shown to be lethal under anoxic conditions. We also show that the two-component system RoxS/RoxR and FliA are important for virulence and swarming/swimming, respectively.
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Butt AT, Banyard CD, Haldipurkar SS, Agnoli K, Mohsin M, Vitovski S, Paleja A, Tang Y, Lomax R, Ye F, Green J, Thomas M. OUP accepted manuscript. Nucleic Acids Res 2022; 50:3709-3726. [PMID: 35234897 PMCID: PMC9023288 DOI: 10.1093/nar/gkac137] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 01/28/2022] [Accepted: 02/14/2022] [Indexed: 11/14/2022] Open
Abstract
Burkholderia cenocepacia is an opportunistic pathogen that causes severe infections of the cystic fibrosis (CF) lung. To acquire iron, B. cenocepacia secretes the Fe(III)-binding compound, ornibactin. Genes for synthesis and utilisation of ornibactin are served by the iron starvation (IS) extracytoplasmic function (ECF) σ factor, OrbS. Transcription of orbS is regulated in response to the prevailing iron concentration by the ferric uptake regulator (Fur), such that orbS expression is repressed under iron-sufficient conditions. Here we show that, in addition to Fur-mediated regulation of orbS, the OrbS protein itself responds to intracellular iron availability. Substitution of cysteine residues in the C-terminal region of OrbS diminished the ability to respond to Fe(II) in vivo. Accordingly, whilst Fe(II) impaired transcription from and recognition of OrbS-dependent promoters in vitro by inhibiting the binding of OrbS to core RNA polymerase (RNAP), the cysteine-substituted OrbS variant was less responsive to Fe(II). Thus, the cysteine residues within the C-terminal region of OrbS contribute to an iron-sensing motif that serves as an on-board ‘anti-σ factor’ in the presence of Fe(II). A model to account for the presence two regulators (Fur and OrbS) that respond to the same intracellular Fe(II) signal to control ornibactin synthesis and utilisation is discussed.
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Affiliation(s)
- Aaron T Butt
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Christopher D Banyard
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Sayali S Haldipurkar
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Kirsty Agnoli
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Muslim I Mohsin
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Srdjan Vitovski
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Ameya Paleja
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Yingzhi Tang
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Rebecca Lomax
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield S10 2RX, UK
| | - Fuzhou Ye
- Section of Structural Biology, Department of Infectious Disease, Imperial College London, Sir Alexander Fleming Building, South Kensington, London SW7 2AZ, UK
| | - Jeffrey Green
- Correspondence may also be addressed to Jeffrey Green. Tel: +44 114 222 4403; Fax: +44 114 222 2800;
| | - Mark S Thomas
- To whom correspondence should be addressed. Tel: +44 114 215 9557; Fax: +44 114 271 1863;
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Methodological tools to study species of the genus Burkholderia. Appl Microbiol Biotechnol 2021; 105:9019-9034. [PMID: 34755214 PMCID: PMC8578011 DOI: 10.1007/s00253-021-11667-3] [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: 09/13/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 11/26/2022]
Abstract
Bacteria belonging to the Burkholderia genus are extremely versatile and diverse. They can be environmental isolates, opportunistic pathogens in cystic fibrosis, immunocompromised or chronic granulomatous disease patients, or cause disease in healthy people (e.g., Burkholderia pseudomallei) or animals (as in the case of Burkholderia mallei). Since the genus was separated from the Pseudomonas one in the 1990s, the methodological tools to study and characterize these bacteria are evolving fast. Here we reviewed the techniques used in the last few years to update the taxonomy of the genus, to study gene functions and regulations, to deepen the knowledge on the drug resistance which characterizes these bacteria, and to elucidate their mechanisms to establish infections. The availability of these tools significantly impacts the quality of research on Burkholderia and the choice of the most appropriated is fundamental for a precise characterization of the species of interest. Key points • Updated techniques to study the genus Burkholderia were reviewed. • Taxonomy, genomics, assays, and animal models were described. • A comprehensive overview on recent advances in Burkholderia studies was made.
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Metabolomic profiling of Burkholderia cenocepacia in synthetic cystic fibrosis sputum medium reveals nutrient environment-specific production of virulence factors. Sci Rep 2021; 11:21419. [PMID: 34725378 PMCID: PMC8560942 DOI: 10.1038/s41598-021-00421-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 10/12/2021] [Indexed: 12/13/2022] Open
Abstract
Infections by Burkholderia cenocepacia lead to life-threatening disease in immunocompromised individuals, including those living with cystic fibrosis (CF). While genetic variation in various B. cenocepacia strains has been reported, it remains unclear how the chemical environment of CF lung influences the production of small molecule virulence factors by these strains. Here we compare metabolomes of three clinical B. cenocepacia strains in synthetic CF sputum medium (SCFM2) and in a routine laboratory medium (LB), in the presence and absence of the antibiotic trimethoprim. Using a mass spectrometry-based untargeted metabolomics approach, we identify several compound classes which are differentially produced in SCFM2 compared to LB media, including siderophores, antimicrobials, quorum sensing signals, and various lipids. Furthermore, we describe that specific metabolites are induced in the presence of the antibiotic trimethoprim only in SCFM2 when compared to LB. Herein, C13-acyl-homoserine lactone, a quorum sensing signal previously not known to be produced by B. cenocepacia as well as pyochelin-type siderophores were exclusively detected during growth in SCFM2 in the presence of trimethoprim. The comparative metabolomics approach described in this study provides insight into environment-dependent production of secondary metabolites by B. cenocepacia strains and suggests future work which could identify personalized strain-specific regulatory mechanisms involved in production of secondary metabolites. Investigations into whether antibiotics with different mechanisms of action induce similar metabolic alterations will inform development of combination treatments aimed at effective clearance of Burkholderia spp. pathogens.
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Hayes AJ, Lewis JM, Davies MR, Scott NE. Burkholderia PglL enzymes are Serine preferring oligosaccharyltransferases which target conserved proteins across the Burkholderia genus. Commun Biol 2021; 4:1045. [PMID: 34493791 PMCID: PMC8423747 DOI: 10.1038/s42003-021-02588-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 08/23/2021] [Indexed: 12/14/2022] Open
Abstract
Glycosylation is increasingly recognised as a common protein modification within bacterial proteomes. While great strides have been made in identifying species that contain glycosylation systems, our understanding of the proteins and sites targeted by these systems is far more limited. Within this work we explore the conservation of glycoproteins and glycosylation sites across the pan-Burkholderia glycoproteome. Using a multi-protease glycoproteomic approach, we generate high-confidence glycoproteomes in two widely utilized B. cenocepacia strains, K56-2 and H111. This resource reveals glycosylation occurs exclusively at Serine residues and that glycoproteins/glycosylation sites are highly conserved across B. cenocepacia isolates. This preference for glycosylation at Serine residues is observed across at least 9 Burkholderia glycoproteomes, supporting that Serine is the dominant residue targeted by PglL-mediated glycosylation across the Burkholderia genus. Combined, this work demonstrates that PglL enzymes of the Burkholderia genus are Serine-preferring oligosaccharyltransferases that target conserved and shared protein substrates. Hayes et al provide a glycosylation site focused analysis of the glycoproteome of two widely utilized B. cenocepacia strains, K56-2 and H111. This team demonstrates that within these glycoproteomes Serine is the sole residue targeted for protein glycosylation and that glycoproteins/glycosylation sites are highly conserved across B. cenocepacia isolates.
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Affiliation(s)
- Andrew J Hayes
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Jessica M Lewis
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Mark R Davies
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Nichollas E Scott
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia.
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McAvoy AC, Jaiyesimi O, Threatt PH, Seladi T, Goldberg JB, da Silva RR, Garg N. Differences in Cystic Fibrosis-Associated Burkholderia spp. Bacteria Metabolomes after Exposure to the Antibiotic Trimethoprim. ACS Infect Dis 2020; 6:1154-1168. [PMID: 32212725 DOI: 10.1021/acsinfecdis.9b00513] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The Burkholderia cepacia complex is a group of closely related bacterial species with large genomes that infect immunocompromised individuals and those living with cystic fibrosis. Some of these species are found more frequently and cause more severe disease than others, yet metabolomic differences between these have not been described. Furthermore, our understanding of how these species respond to antibiotics is limited. We investigated the metabolomics differences between three most prevalent Burkholderia spp. associated with cystic fibrosis: B. cenocepacia, B. multivorans, and B. dolosa in the presence and absence of the antibiotic trimethoprim. Using a combination of supervised and unsupervised metabolomics data visualization and analysis tools, we describe the overall differences between strains of the same species and between species. Specifically, we report, for the first time, the role of the pyomelanin pathway in the metabolism of trimethoprim. We also report differences in the detection of known secondary metabolites such as fragin, ornibactin, and N-acylhomoserine lactones and their analogs in closely related strains. Furthermore, we highlight the potential for the discovery of new secondary metabolites in clinical strains of Burkholderia spp. The metabolomics differences described in this study highlight the personalized nature of closely related Burkholderia strains.
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Affiliation(s)
- Andrew C. McAvoy
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Drive, Atlanta, Georgia 30332-2000, United States
| | - Olakunle Jaiyesimi
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Drive, Atlanta, Georgia 30332-2000, United States
| | - Paxton H. Threatt
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Drive, Atlanta, Georgia 30332-2000, United States
| | - Tyler Seladi
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Drive, Atlanta, Georgia 30332-2000, United States
| | - Joanna B. Goldberg
- Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Emory University School of Medicine, 1510 Clifton Road NE, Suite 3009, Atlanta, Georgia 30322, United States
- Emory-Children’s Cystic Fibrosis Center, Atlanta, Georgia 30322, United States
| | - Ricardo R. da Silva
- School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Av. do Café - Vila Monte Alegre, Ribeirão Preto, São Paulo 14040-903, Brazil
| | - Neha Garg
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 950 Atlantic Drive, Atlanta, Georgia 30332-2000, United States
- Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Emory University School of Medicine, 1510 Clifton Road NE, Suite 3009, Atlanta, Georgia 30322, United States
- Center for Microbial Dynamics and Infection, School of Biological Sciences, Georgia Institute of Technology, 311 Ferst Drive, ES&T, Atlanta, Georgia 30332, United States
- Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, 311 Ferst Drive, ES&T, Atlanta, Georgia 30322, United States
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Phenylacetyl Coenzyme A, Not Phenylacetic Acid, Attenuates CepIR-Regulated Virulence in Burkholderia cenocepacia. Appl Environ Microbiol 2019; 85:AEM.01594-19. [PMID: 31585996 DOI: 10.1128/aem.01594-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 09/30/2019] [Indexed: 11/20/2022] Open
Abstract
During phenylalanine catabolism, phenylacetic acid (PAA) is converted to phenylacetyl coenzyme A (PAA-CoA) by a ligase, PaaK, and then PAA-CoA is epoxidized by a multicomponent monooxygenase, PaaABCDE, before further degradation through the tricarboxylic acid (TCA) cycle. In the opportunistic pathogen Burkholderia cenocepacia, loss of paaABCDE attenuates virulence factor expression, which is under the control of the LuxIR-like quorum sensing (QS) system, CepIR. To further investigate the link between CepIR-regulated virulence and PAA catabolism, we created knockout mutants of the first step of the pathway (PAA-CoA synthesis by PaaK) and characterized them in comparison to a paaABCDE mutant using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and virulence assays. We found that while loss of PaaABCDE decreased virulence, deletion of the paaK genes resulted in a more virulent phenotype than that of the wild-type strain. Deletion of either paaK or paaABCDE led to higher levels of released PAA but no differences in levels of internal accumulation compared to the wild-type level. While we found no evidence of direct cepIR downregulation by PAA-CoA or PAA, a low-virulence cepR mutant reverted to a virulent phenotype upon removal of the paaK genes. On the other hand, removal of paaABCDE in the cepR mutant did not impact its attenuated phenotype. Together, our results suggest an indirect role for PAA-CoA in suppressing B. cenocepacia CepIR-activated virulence.IMPORTANCE The opportunistic pathogen Burkholderia cenocepacia uses a chemical signal process called quorum sensing (QS) to produce virulence factors. In B. cenocepacia, QS relies on the presence of the transcriptional regulator CepR which, upon binding QS signal molecules, activates virulence. In this work, we found that even in the absence of CepR, B. cenocepacia can elicit a pathogenic response if phenylacetyl-CoA, an intermediate of the phenylacetic acid degradation pathway, is not produced. Instead, accumulation of phenylacetyl-CoA appears to attenuate pathogenicity. Therefore, we have discovered that it is possible to trigger virulence in the absence of CepR, challenging the classical view of activation of virulence by this QS mechanism. Our work provides new insight into the relationship between metabolism and virulence in opportunistic bacteria. We propose that in the event that QS signaling molecules cannot accumulate to trigger a pathogenic response, a metabolic signal can still activate virulence in B. cenocepacia.
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Oppy CC, Jebeli L, Kuba M, Oates CV, Strugnell R, Edgington-Mitchell LE, Valvano MA, Hartland EL, Newton HJ, Scott NE. Loss of O-Linked Protein Glycosylation in Burkholderia cenocepacia Impairs Biofilm Formation and Siderophore Activity and Alters Transcriptional Regulators. mSphere 2019; 4:e00660-19. [PMID: 31722994 PMCID: PMC6854043 DOI: 10.1128/msphere.00660-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 10/24/2019] [Indexed: 02/07/2023] Open
Abstract
O-linked protein glycosylation is a conserved feature of the Burkholderia genus. The addition of the trisaccharide β-Gal-(1,3)-α-GalNAc-(1,3)-β-GalNAc to membrane exported proteins in Burkholderia cenocepacia is required for bacterial fitness and resistance to environmental stress. However, the underlying causes of the defects observed in the absence of glycosylation are unclear. Using proteomics, luciferase reporter assays, and DNA cross-linking, we demonstrate the loss of glycosylation leads to changes in transcriptional regulation of multiple proteins, including the repression of the master quorum CepR/I. These proteomic and transcriptional alterations lead to the abolition of biofilm formation and defects in siderophore activity. Surprisingly, the abundance of most of the known glycosylated proteins did not significantly change in the glycosylation-defective mutants, except for BCAL1086 and BCAL2974, which were found in reduced amounts, suggesting they could be degraded. However, the loss of these two proteins was not responsible for driving the proteomic alterations, biofilm formation, or siderophore activity. Together, our results show that loss of glycosylation in B. cenocepacia results in a global cell reprogramming via alteration of the transcriptional regulatory systems, which cannot be explained by the abundance changes in known B. cenocepacia glycoproteins.IMPORTANCE Protein glycosylation is increasingly recognized as a common posttranslational protein modification in bacterial species. Despite this commonality, our understanding of the role of most glycosylation systems in bacterial physiology and pathogenesis is incomplete. In this work, we investigated the effect of the disruption of O-linked glycosylation in the opportunistic pathogen Burkholderia cenocepacia using a combination of proteomic, molecular, and phenotypic assays. We find that in contrast to recent findings on the N-linked glycosylation systems of Campylobacter jejuni, O-linked glycosylation does not appear to play a role in proteome stabilization of most glycoproteins. Our results reveal that loss of glycosylation in B. cenocepacia strains leads to global proteome and transcriptional changes, including the repression of the quorum-sensing regulator cepR (BCAM1868) gene. These alterations lead to dramatic phenotypic changes in glycosylation-null strains, which are paralleled by both global proteomic and transcriptional alterations, which do not appear to directly result from the loss of glycosylation per se. This research unravels the pleiotropic effects of O-linked glycosylation in B. cenocepacia, demonstrating that its loss does not simply affect the stability of the glycoproteome, but also interferes with transcription and the broader proteome.
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Affiliation(s)
- Cameron C Oppy
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
| | - Leila Jebeli
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Miku Kuba
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Clare V Oates
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Richard Strugnell
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Laura E Edgington-Mitchell
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
- Department of Oral and Maxillofacial Surgery, New York University College of Dentistry, Bluestone Center for Clinical Research, New York, New York, USA
| | - Miguel A Valvano
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Elizabeth L Hartland
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Hayley J Newton
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Nichollas E Scott
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
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Wallner A, King E, Ngonkeu ELM, Moulin L, Béna G. Genomic analyses of Burkholderia cenocepacia reveal multiple species with differential host-adaptation to plants and humans. BMC Genomics 2019; 20:803. [PMID: 31684866 PMCID: PMC6829993 DOI: 10.1186/s12864-019-6186-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 10/15/2019] [Indexed: 12/17/2022] Open
Abstract
Background Burkholderia cenocepacia is a human opportunistic pathogen causing devastating symptoms in patients suffering from immunodeficiency and cystic fibrosis. Out of the 303 B. cenocepacia strains with available genomes, the large majority were isolated from a clinical context. However, several isolates originate from other environmental sources ranging from aerosols to plant endosphere. Plants can represent reservoirs for human infections as some pathogens can survive and sometimes proliferate in the rhizosphere. We therefore investigated if B. cenocepacia had the same potential. Results We selected genome sequences from 31 different strains, representative of the diversity of ecological niches of B. cenocepacia, and conducted comparative genomic analyses in the aim of finding specific niche or host-related genetic determinants. Phylogenetic analyses and whole genome average nucleotide identity suggest that strains, registered as B. cenocepacia, belong to at least two different species. Core-genome analyses show that the clade enriched in environmental isolates lacks multiple key virulence factors, which are conserved in the sister clade where most clinical isolates fall, including the highly virulent ET12 lineage. Similarly, several plant associated genes display an opposite distribution between the two clades. Finally, we suggest that B. cenocepacia underwent a host jump from plants/environment to animals, as supported by the phylogenetic analysis. We eventually propose a name for the new species that lacks several genetic traits involved in human virulence. Conclusion Regardless of the method used, our studies resulted in a disunited perspective of the B. cenocepacia species. Strains currently affiliated to this taxon belong to at least two distinct species, one having lost several determining animal virulence factors.
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Affiliation(s)
- Adrian Wallner
- IRD, CIRAD, University of Montpellier, IPME; 911 avenue Agropolis, BP 64501, 34394, Montpellier, France
| | - Eoghan King
- IRD, CIRAD, University of Montpellier, IPME; 911 avenue Agropolis, BP 64501, 34394, Montpellier, France
| | - Eddy L M Ngonkeu
- Institute of Agronomic Research for Development (IRAD), PO Box 2123, Yaoundé, Cameroon
| | - Lionel Moulin
- IRD, CIRAD, University of Montpellier, IPME; 911 avenue Agropolis, BP 64501, 34394, Montpellier, France
| | - Gilles Béna
- IRD, CIRAD, University of Montpellier, IPME; 911 avenue Agropolis, BP 64501, 34394, Montpellier, France.
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Potent modulation of the CepR quorum sensing receptor and virulence in a Burkholderia cepacia complex member using non-native lactone ligands. Sci Rep 2019; 9:13449. [PMID: 31530834 PMCID: PMC6748986 DOI: 10.1038/s41598-019-49693-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 08/29/2019] [Indexed: 12/13/2022] Open
Abstract
The Burkholderia cepacia complex (Bcc) is a family of closely related bacterial pathogens that are the causative agent of deadly human infections. Virulence in Bcc species has been shown to be controlled by the CepI/CepR quorum sensing (QS) system, which is mediated by an N-acyl L-homoserine lactone (AHL) signal (C8-AHL) and its cognate LuxR-type receptor (CepR). Chemical strategies to block QS in Bcc members would represent an approach to intercept this bacterial communication process and further delineate its role in infection. In the current study, we sought to identify non-native AHLs capable of agonizing or antagonizing CepR, and thereby QS, in a Bcc member. We screened a library of AHL analogs in cell-based reporters for CepR, and identified numerous highly potent CepR agonists and antagonists. These compounds remain active in a Bcc member, B. multivorans, with one agonist 250-fold more potent than the native ligand C8-AHL, and can affect QS-controlled motility. Further, the CepR antagonists prolong C. elegans survival in an infection model. These AHL analogs are the first reported non-native molecules that both directly modulate CepR and impact QS-controlled phenotypes in a Bcc member, and represent valuable chemical tools to assess the role of QS in Bcc infections.
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New Perspectives on Galleria mellonella Larvae as a Host Model Using Riemerella anatipestifer as a Proof of Concept. Infect Immun 2019; 87:IAI.00072-19. [PMID: 31160365 DOI: 10.1128/iai.00072-19] [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: 01/25/2019] [Accepted: 05/16/2019] [Indexed: 02/07/2023] Open
Abstract
Galleria mellonella larvae have been used as a host model to study interactions between pathogens and hosts for several years. However, whether the model is useful to interrogate Riemerella anatipestifer infection biology remained unknown. This study aimed to exploit the potential of G. mellonella larvae and reveal their limitations as a host model for R. anatipestifer infection. G. mellonella larvae were shown to be effective for virulence evaluations of different R. anatipestifer strains. Furthermore, the virulent strain R. anatipestifer CH-1 had a stronger ability to proliferate than the attenuated strain R. anatipestifer ATCC 11845 in both G. mellonella larvae and ducklings. Unconventionally it was shown that G. mellonella larvae cannot be used to evaluate the efficacy of antimicrobials and their combinations. Additionally, it was shown that certain virulence factors, such as OmpA (B739_0861), B739_1208, B739_1343, and Wza (B739_1124), were specific only for ducklings, suggesting that G. mellonella larvae must be cautiously used to identify virulence factors of R. anatipestifer Evaluation of heme uptake-related virulence genes, such as tonB1 and tonB2, required preincubating the strains with hemoglobin before infection of G. mellonella larvae since R. anatipestifer cannot obtain a heme source from G. mellonella larvae. In conclusion, this study revealed the applicability and limitations of G. mellonella as a model with which to study the pathogen-host interaction, particularly in the context of R. anatipestifer infection.
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Quorum Sensing as Antivirulence Target in Cystic Fibrosis Pathogens. Int J Mol Sci 2019; 20:ijms20081838. [PMID: 31013936 PMCID: PMC6515091 DOI: 10.3390/ijms20081838] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/11/2019] [Accepted: 04/11/2019] [Indexed: 12/17/2022] Open
Abstract
Cystic fibrosis (CF) is an autosomal recessive genetic disorder which leads to the secretion of a viscous mucus layer on the respiratory epithelium that facilitates colonization by various bacterial pathogens. The problem of drug resistance has been reported for all the species able to colonize the lung of CF patients, so alternative treatments are urgently needed. In this context, a valid approach is to investigate new natural and synthetic molecules for their ability to counteract alternative pathways, such as virulence regulating quorum sensing (QS). In this review we describe the pathogens most commonly associated with CF lung infections: Staphylococcus aureus, Pseudomonas aeruginosa, species of the Burkholderia cepacia complex and the emerging pathogens Stenotrophomonas maltophilia, Haemophilus influenzae and non-tuberculous Mycobacteria. For each bacterium, the QS system(s) and the molecules targeting the different components of this pathway are described. The amount of investigations published in the last five years clearly indicate the interest and the expectations on antivirulence therapy as an alternative to classical antibiotics.
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18
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Environmental interactions are regulated by temperature in Burkholderia seminalis TC3.4.2R3. Sci Rep 2019; 9:5486. [PMID: 30940839 PMCID: PMC6445077 DOI: 10.1038/s41598-019-41778-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 03/12/2019] [Indexed: 11/08/2022] Open
Abstract
Burkholderia seminalis strain TC3.4.2R3 is an endophytic bacterium isolated from sugarcane roots that produces antimicrobial compounds, facilitating its ability to act as a biocontrol agent against phytopathogenic bacteria. In this study, we investigated the thermoregulation of B. seminalis TC3.4.2R3 at 28 °C (environmental stimulus) and 37 °C (host-associated stimulus) at the transcriptional and phenotypic levels. The production of biofilms and exopolysaccharides such as capsular polysaccharides and the biocontrol of phytopathogenic fungi were enhanced at 28 °C. At 37 °C, several metabolic pathways were activated, particularly those implicated in energy production, stress responses and the biosynthesis of transporters. Motility, growth and virulence in the Galleria mellonella larvae infection model were more significant at 37 °C. Our data suggest that the regulation of capsule expression could be important in virulence against G. mellonella larvae at 37 °C. In contrast, B. seminalis TC3.4.2R3 failed to cause death in infected BALB/c mice, even at an infective dose of 107 CFU.mL-1. We conclude that temperature drives the regulation of gene expression in B. seminalis during its interactions with the environment.
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Furlan JPR, Pitondo-Silva A, Braz VS, Gallo IFL, Stehling EG. Evaluation of different molecular and phenotypic methods for identification of environmental Burkholderia cepacia complex. World J Microbiol Biotechnol 2019; 35:39. [PMID: 30739255 DOI: 10.1007/s11274-019-2614-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 02/05/2019] [Indexed: 12/01/2022]
Abstract
The correct identification of different genera and bacterial species is essential, especially when these bacteria cause infections and appropriate therapies need to be chosen. Bacteria belonging to the Burkholderia cepacia complex are considered important opportunistic pathogens, causing different types of infections in immunocompromised, principally in patients with cystic fibrosis. Twenty-one isolates were obtained from different soil samples and identified by sequencing of 16S rRNA, 23S rRNA, recA gene, MLST and by VITEK 2 and MALDI-TOF MS systems. Then, statistical analyses were performed. VITEK 2 and MALDI-TOF MS systems showed different bacterial genera. Sequencing of the 16S rRNA, 23S rRNA gene and amplification of recA gene showed that all the isolates belong to the B. cepacia complex. Sequencing of the recA gene showed a predominance of B. cenocepacia. The PCR of the recA gene showed a high specificity when it is necessary to identify the bacteria belonging to the B. cepacia complex in comparison with 16S and 23S rRNA genes sequencing. MLST analyzes showed a diversity of STs, which have not yet been correlated to the species. Phenotypic identification was not suitable for the identification of these pathogens since in many cases different genera have been reported, including identification by using MALDI-TOF MS.
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Affiliation(s)
- João Pedro Rueda Furlan
- Department of Clinical Analysis, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Av. do Café S/N. Monte Alegre, Ribeirão Preto, SP, 14040-903, Brazil
| | - André Pitondo-Silva
- Department of Clinical Analysis, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Av. do Café S/N. Monte Alegre, Ribeirão Preto, SP, 14040-903, Brazil.,School of Dentistry, University of Ribeirao Preto (UNAERP), Ribeirão Preto, Brazil
| | - Vânia Santos Braz
- Department of Clinical Analysis, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Av. do Café S/N. Monte Alegre, Ribeirão Preto, SP, 14040-903, Brazil
| | - Inara Fernanda Lage Gallo
- Department of Clinical Analysis, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Av. do Café S/N. Monte Alegre, Ribeirão Preto, SP, 14040-903, Brazil
| | - Eliana Guedes Stehling
- Department of Clinical Analysis, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo (USP), Av. do Café S/N. Monte Alegre, Ribeirão Preto, SP, 14040-903, Brazil.
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20
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Spiewak HL, Shastri S, Zhang L, Schwager S, Eberl L, Vergunst AC, Thomas MS. Burkholderia cenocepacia utilizes a type VI secretion system for bacterial competition. Microbiologyopen 2019; 8:e00774. [PMID: 30628184 PMCID: PMC6612558 DOI: 10.1002/mbo3.774] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/07/2018] [Accepted: 11/07/2018] [Indexed: 01/24/2023] Open
Abstract
Burkholderia cenocepacia is an opportunistic bacterial pathogen that poses a significant threat to individuals with cystic fibrosis by provoking a strong inflammatory response within the lung. It possesses a type VI secretion system (T6SS), a secretory apparatus that can perforate the cellular membrane of other bacterial species and/or eukaryotic targets, to deliver an arsenal of effector proteins. The B. cenocepacia T6SS (T6SS-1) has been shown to be implicated in virulence in rats and contributes toward actin rearrangements and inflammasome activation in B. cenocepacia-infected macrophages. Here, we present bioinformatics evidence to suggest that T6SS-1 is the archetype T6SS in the Burkholderia genus. We show that B. cenocepacia T6SS-1 is active under normal laboratory growth conditions and displays antibacterial activity against other Gram-negative bacterial species. Moreover, B. cenocepacia T6SS-1 is not required for virulence in three eukaryotic infection models. Bioinformatics analysis identified several candidate T6SS-dependent effectors that may play a role in the antibacterial activity of B. cenocepacia T6SS-1. We conclude that B. cenocepacia T6SS-1 plays an important role in bacterial competition for this organism, and probably in all Burkholderia species that possess this system, thereby broadening the range of species that utilize the T6SS for this purpose.
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Affiliation(s)
- Helena L. Spiewak
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK,Present address:
Northern Genetics Service, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Institute of Genetic MedicineInternational Centre for LifeNewcastle upon TyneUK
| | - Sravanthi Shastri
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK
| | - Lili Zhang
- VBMI, INSERM, Université de MontpellierNîmesFrance,Present address:
Section of Molecular Biology, Division of Biological SciencesUniversity of California, San DiegoLa JollaCalifornia
| | - Stephan Schwager
- Department of Plant and Microbial BiologyUniversity of ZurichZurichSwitzerland,Present address:
Analytical ChemistrySynthes GmbHOberdorf BLSwitzerland
| | - Leo Eberl
- Department of Plant and Microbial BiologyUniversity of ZurichZurichSwitzerland
| | | | - Mark S. Thomas
- Department of Infection, Immunity and Cardiovascular Disease, The Medical SchoolThe University of SheffieldSheffieldUK
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21
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Duckweed (Lemna minor) and Alfalfa (Medicago sativa) as Bacterial Infection Model Systems. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2018; 1898:191-198. [PMID: 30570734 DOI: 10.1007/978-1-4939-8940-9_16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Alternative animal host models of bacterial infection have been developed which reproduce some of the disease conditions observed in higher animals. Analogously, plants are useful for modeling bacterial pathogenesis, in some cases revealing broadly conserved infection mechanisms. Similar to animals, plants have been shown to possess innate immune systems that respond to invading viruses, bacteria, and fungi. Plant infection models often yield results faster, are more convenient, and less expensive than many animal infection models. Here, we describe the use of two different plant-based infection models for the discovery of virulence genes and factors involved in bacterial pathogenesis.
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22
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Gomes MC, Tasrini Y, Subramoni S, Agnoli K, Feliciano JR, Eberl L, Sokol P, O’Callaghan D, Vergunst AC. The afc antifungal activity cluster, which is under tight regulatory control of ShvR, is essential for transition from intracellular persistence of Burkholderia cenocepacia to acute pro-inflammatory infection. PLoS Pathog 2018; 14:e1007473. [PMID: 30513124 PMCID: PMC6301696 DOI: 10.1371/journal.ppat.1007473] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 12/20/2018] [Accepted: 11/19/2018] [Indexed: 01/22/2023] Open
Abstract
The opportunistic pathogen Burkholderia cenocepacia is particularly life-threatening for cystic fibrosis (CF) patients. Chronic lung infections with these bacteria can rapidly develop into fatal pulmonary necrosis and septicaemia. We have recently shown that macrophages are a critical site for replication of B. cenocepacia K56-2 and the induction of fatal pro-inflammatory responses using a zebrafish infection model. Here, we show that ShvR, a LysR-type transcriptional regulator that is important for biofilm formation, rough colony morphotype and inflammation in a rat lung infection model, is also required for the induction of fatal pro-inflammatory responses in zebrafish larvae. ShvR was not essential, however, for bacterial survival and replication in macrophages. Temporal, rhamnose-induced restoration of shvR expression in the shvR mutant during intramacrophage stages unequivocally demonstrated a key role for ShvR in transition from intracellular persistence to acute fatal pro-inflammatory disease. ShvR has been previously shown to tightly control the expression of the adjacent afc gene cluster, which specifies the synthesis of a lipopeptide with antifungal activity. Mutation of afcE, encoding an acyl-CoA dehydrogenase, has been shown to give similar phenotypes as the shvR mutant. We found that, like shvR, afcE is also critical for the switch from intracellular persistence to fatal infection in zebrafish. The closely related B. cenocepacia H111 has been shown to be less virulent than K56-2 in several infection models, including Galleria mellonella and rats. Interestingly, constitutive expression of shvR in H111 increased virulence in zebrafish larvae to almost K56-2 levels in a manner that absolutely required afc. These data confirm a critical role for afc in acute virulence caused by B. cenocepacia that depends on strain-specific regulatory control by ShvR. We propose that ShvR and AFC are important virulence factors of the more virulent Bcc species, either through pro-inflammatory effects of the lipopeptide AFC, or through AFC-dependent membrane properties.
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Affiliation(s)
| | - Yara Tasrini
- VBMI, INSERM, Université de Montpellier, Nîmes, France
| | - Sujatha Subramoni
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Canada
| | - Kirsty Agnoli
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | | | - Leo Eberl
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Pamela Sokol
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Canada
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Magana M, Sereti C, Ioannidis A, Mitchell CA, Ball AR, Magiorkinis E, Chatzipanagiotou S, Hamblin MR, Hadjifrangiskou M, Tegos GP. Options and Limitations in Clinical Investigation of Bacterial Biofilms. Clin Microbiol Rev 2018; 31:e00084-16. [PMID: 29618576 PMCID: PMC6056845 DOI: 10.1128/cmr.00084-16] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Bacteria can form single- and multispecies biofilms exhibiting diverse features based upon the microbial composition of their community and microenvironment. The study of bacterial biofilm development has received great interest in the past 20 years and is motivated by the elegant complexity characteristic of these multicellular communities and their role in infectious diseases. Biofilms can thrive on virtually any surface and can be beneficial or detrimental based upon the community's interplay and the surface. Advances in the understanding of structural and functional variations and the roles that biofilms play in disease and host-pathogen interactions have been addressed through comprehensive literature searches. In this review article, a synopsis of the methodological landscape of biofilm analysis is provided, including an evaluation of the current trends in methodological research. We deem this worthwhile because a keyword-oriented bibliographical search reveals that less than 5% of the biofilm literature is devoted to methodology. In this report, we (i) summarize current methodologies for biofilm characterization, monitoring, and quantification; (ii) discuss advances in the discovery of effective imaging and sensing tools and modalities; (iii) provide an overview of tailored animal models that assess features of biofilm infections; and (iv) make recommendations defining the most appropriate methodological tools for clinical settings.
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Affiliation(s)
- Maria Magana
- Department of Clinical Microbiology, Athens Medical School, Aeginition Hospital, Athens, Greece
| | - Christina Sereti
- Department of Clinical Microbiology, Athens Medical School, Aeginition Hospital, Athens, Greece
- Department of Microbiology, Thriassio General Hospital, Attiki, Greece
| | - Anastasios Ioannidis
- Department of Clinical Microbiology, Athens Medical School, Aeginition Hospital, Athens, Greece
- Department of Nursing, Faculty of Human Movement and Quality of Life Sciences, University of Peloponnese, Sparta, Greece
| | - Courtney A Mitchell
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee, USA
| | - Anthony R Ball
- Gliese 623b, Mendon, Massachusetts, USA
- GAMA Therapeutics LLC, Pepperell, Massachusetts, USA
| | - Emmanouil Magiorkinis
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, University of Athens, Athens-Goudi, Greece
| | | | - Michael R Hamblin
- Harvard-MIT Division of Health Science and Technology, Cambridge, Massachusetts, USA
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Maria Hadjifrangiskou
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - George P Tegos
- Gliese 623b, Mendon, Massachusetts, USA
- GAMA Therapeutics LLC, Pepperell, Massachusetts, USA
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24
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Wong YC, Abd El Ghany M, Ghazzali RNM, Yap SJ, Hoh CC, Pain A, Nathan S. Genetic Determinants Associated With in Vivo Survival of Burkholderia cenocepacia in the Caenorhabditis elegans Model. Front Microbiol 2018; 9:1118. [PMID: 29896180 PMCID: PMC5987112 DOI: 10.3389/fmicb.2018.01118] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 05/11/2018] [Indexed: 12/15/2022] Open
Abstract
A Burkholderia cenocepacia infection usually leads to reduced survival and fatal cepacia syndrome in cystic fibrosis patients. The identification of B. cenocepacia essential genes for in vivo survival is key to designing new anti-infectives therapies. We used the Transposon-Directed Insertion Sequencing (TraDIS) approach to identify genes required for B. cenocepacia survival in the model infection host, Caenorhabditis elegans. A B. cenocepacia J2315 transposon pool of ∼500,000 mutants was used to infect C. elegans. We identified 178 genes as crucial for B. cenocepacia survival in the infected nematode. The majority of these genes code for proteins of unknown function, many of which are encoded by the genomic island BcenGI13, while other gene products are involved in nutrient acquisition, general stress responses and LPS O-antigen biosynthesis. Deletion of the glycosyltransferase gene wbxB and a histone-like nucleoid structuring (H-NS) protein-encoding gene (BCAL0154) reduced bacterial accumulation and attenuated virulence in C. elegans. Further analysis using quantitative RT-PCR indicated that BCAL0154 modulates B. cenocepacia pathogenesis via transcriptional regulation of motility-associated genes including fliC, fliG, flhD, and cheB1. This screen has successfully identified genes required for B. cenocepacia survival within the host-associated environment, many of which are potential targets for developing new antimicrobials.
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Affiliation(s)
- Yee-Chin Wong
- School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | - Moataz Abd El Ghany
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,The Westmead Institute for Medical Research and The Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Sydney, NSW, Australia
| | - Raeece N M Ghazzali
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | | | | | - Arnab Pain
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Sheila Nathan
- School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia
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25
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Furlan JPR, Sanchez DG, Fachin AL, Stehling EG. Presence of β-Lactamase Encoding Genes inBurkholderia cepaciaComplex Isolated from Soil. Microb Drug Resist 2018; 24:347-352. [DOI: 10.1089/mdr.2017.0069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- João Pedro Rueda Furlan
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Danilo Garcia Sanchez
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Ana Lúcia Fachin
- Unidade de Biotecnologia, Universidade de Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil
| | - Eliana Guedes Stehling
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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26
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[The controversial Burkholderia cepacia complex, a group of plant growth promoting species and plant, animals and human pathogens]. Rev Argent Microbiol 2018; 51:84-92. [PMID: 29691107 DOI: 10.1016/j.ram.2018.01.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 10/10/2017] [Accepted: 01/03/2018] [Indexed: 11/22/2022] Open
Abstract
The Burkholderia cepacia complex is a group of 22 species, which are known as opportunistic pathogens in immunocompromised people, especially those suffering from cystic fibrosis. It is also found in nosocomial infections and is difficult to eradicate due to intrinsic resistance to several antibiotics. The species have large genomes (up to 9 Mbp), distributed into 2-5 replicons. These features significantly contribute to genome plasticity, which makes them thrive in different environments like soil, water, plants or even producing nodules in legume plants. Some B. cepacia complex species are beneficial in bioremediation, biocontrol and plant-growth promotion. However, because the B. cepacia complex is involved in human infection, its use in agriculture is restricted. B. cepacia complex is being constantly studied due to the health problems that it causes and because of its agricultural potential. In this review, the history of B. cepacia complex and the most recently published information related to this complex are revised.
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27
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Depluverez S, Daled S, De Waele S, Planckaert S, Schoovaerts J, Deforce D, Devreese B. Microfluidics-based LC-MS MRM approach for the relative quantification of Burkholderia cenocepacia secreted virulence factors. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2018; 32:469-479. [PMID: 29322563 DOI: 10.1002/rcm.8059] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 12/15/2017] [Accepted: 01/02/2018] [Indexed: 06/07/2023]
Abstract
Burkholderia cenocepacia is an opportunistic pathogen that is commonly isolated from patients with cystic fibrosis (CF). Several virulence factors have been identified, including extracellular enzymes that are secreted by type II and type VI secretion systems. The activity of these secretion systems is modulated by quorum sensing. Apart from the classical acylhomoserine lactone quorum sensing, B. cenocepacia also uses the diffusible signal factor system (DSF) i.e. 2-undecenoic acid derivatives that are recognized by specific receptors resulting in changes in biofilm formation, motility and virulence. However, quantitative information on alterations in the actual production and release of virulence factors upon exposure to DSF is lacking. We here describe an approach implementing microfluidics based chromatography combined with single reaction monitoring to quantify protein virulence factors in the secretome of B. cenocepacia.
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Affiliation(s)
- Sofie Depluverez
- Laboratory for Protein Biochemistry and Biomolecular Engineering (L-ProBE), Ghent University, KL Ledeganckstraat 35, B-9000, Ghent, Belgium
| | - Simon Daled
- Laboratory of Pharmaceutical Biotechnology, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Stijn De Waele
- Laboratory for Protein Biochemistry and Biomolecular Engineering (L-ProBE), Ghent University, KL Ledeganckstraat 35, B-9000, Ghent, Belgium
| | - Sören Planckaert
- Laboratory for Protein Biochemistry and Biomolecular Engineering (L-ProBE), Ghent University, KL Ledeganckstraat 35, B-9000, Ghent, Belgium
| | - Jolien Schoovaerts
- Laboratory for Protein Biochemistry and Biomolecular Engineering (L-ProBE), Ghent University, KL Ledeganckstraat 35, B-9000, Ghent, Belgium
| | - Dieter Deforce
- Laboratory of Pharmaceutical Biotechnology, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Bart Devreese
- Laboratory for Protein Biochemistry and Biomolecular Engineering (L-ProBE), Ghent University, KL Ledeganckstraat 35, B-9000, Ghent, Belgium
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28
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Bragonzi A, Paroni M, Pirone L, Coladarci I, Ascenzioni F, Bevivino A. Environmental Burkholderia cenocepacia Strain Enhances Fitness by Serial Passages during Long-Term Chronic Airways Infection in Mice. Int J Mol Sci 2017; 18:ijms18112417. [PMID: 29135920 PMCID: PMC5713385 DOI: 10.3390/ijms18112417] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 11/08/2017] [Accepted: 11/10/2017] [Indexed: 01/17/2023] Open
Abstract
Burkholderia cenocepacia is an important opportunistic pathogen in cystic fibrosis (CF) patients, and has also been isolated from natural environments. In previous work, we explored the virulence and pathogenic potential of environmental B. cenocepacia strains and demonstrated that they do not differ from clinical strains in some pathogenic traits. Here, we investigated the ability of the environmental B. cenocepacia Mex1 strain, isolated from the maize rhizosphere, to persist and increase its virulence after serial passages in a mouse model of chronic infection. B. cenocepacia Mex1 strain, belonging to the recA lineage IIIA, was embedded in agar beads and challenged into the lung of C57Bl/6 mice. The mice were sacrificed after 28 days from infection and their lungs were tested for bacterial loads. Agar beads containing the pool of B. cenocepacia colonies from the four sequential passages were used to infect the mice. The environmental B. cenocepacia strain showed a low incidence of chronic infection after the first passage; after the second, third and fourth passages in mice, its ability to establish chronic infection increased significantly and progressively up to 100%. Colonial morphology analysis and genetic profiling of the Mex1-derived clones recovered after the fourth passage from infected mice revealed that they were indistinguishable from the challenged strain both at phenotypic and genetic level. By testing the virulence of single clones in the Galleria mellonella infection model, we found that two Mex1-derived clones significantly increased their pathogenicity compared to the parental Mex1 strain and behaved similarly to the clinical and epidemic B. cenocepacia LMG16656T. Our findings suggest that serial passages of the environmental B. cenocepacia Mex1 strain in mice resulted in an increased ability to determine chronic lung infection and the appearance of clonal variants with increased virulence in non-vertebrate hosts.
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Affiliation(s)
- Alessandra Bragonzi
- Infections and Cystic Fibrosis Unit, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Moira Paroni
- Infections and Cystic Fibrosis Unit, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy.
- Department of Biosciences, University of Milan, 20133 Milan, Italy.
| | - Luisa Pirone
- Territorial and Production Systems Sustainability Department, ENEA, Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Casaccia Research Center, 00123 Rome, Italy.
| | - Ivan Coladarci
- Biology and Biotechnology Department "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy.
| | - Fiorentina Ascenzioni
- Biology and Biotechnology Department "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy.
| | - Annamaria Bevivino
- Territorial and Production Systems Sustainability Department, ENEA, Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Casaccia Research Center, 00123 Rome, Italy.
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29
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Butt AT, Thomas MS. Iron Acquisition Mechanisms and Their Role in the Virulence of Burkholderia Species. Front Cell Infect Microbiol 2017; 7:460. [PMID: 29164069 PMCID: PMC5681537 DOI: 10.3389/fcimb.2017.00460] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 10/18/2017] [Indexed: 11/19/2022] Open
Abstract
Burkholderia is a genus within the β-Proteobacteriaceae that contains at least 90 validly named species which can be found in a diverse range of environments. A number of pathogenic species occur within the genus. These include Burkholderia cenocepacia and Burkholderia multivorans, opportunistic pathogens that can infect the lungs of patients with cystic fibrosis, and are members of the Burkholderia cepacia complex (Bcc). Burkholderia pseudomallei is also an opportunistic pathogen, but in contrast to Bcc species it causes the tropical human disease melioidosis, while its close relative Burkholderia mallei is the causative agent of glanders in horses. For these pathogens to survive within a host and cause disease they must be able to acquire iron. This chemical element is essential for nearly all living organisms due to its important role in many enzymes and metabolic processes. In the mammalian host, the amount of accessible free iron is negligible due to the low solubility of the metal ion in its higher oxidation state and the tight binding of this element by host proteins such as ferritin and lactoferrin. As with other pathogenic bacteria, Burkholderia species have evolved an array of iron acquisition mechanisms with which to capture iron from the host environment. These mechanisms include the production and utilization of siderophores and the possession of a haem uptake system. Here, we summarize the known mechanisms of iron acquisition in pathogenic Burkholderia species and discuss the evidence for their importance in the context of virulence and the establishment of infection in the host. We have also carried out an extensive bioinformatic analysis to identify which siderophores are produced by each Burkholderia species that is pathogenic to humans.
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Affiliation(s)
- Aaron T Butt
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield, United Kingdom
| | - Mark S Thomas
- Department of Infection, Immunity and Cardiovascular Disease, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield, United Kingdom
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30
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Use of Synthetic Hybrid Strains To Determine the Role of Replicon 3 in Virulence of the Burkholderia cepacia Complex. Appl Environ Microbiol 2017; 83:AEM.00461-17. [PMID: 28432094 DOI: 10.1128/aem.00461-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 04/12/2017] [Indexed: 01/08/2023] Open
Abstract
The Burkholderia cepacia complex (Bcc) displays a wealth of metabolic diversity with great biotechnological potential, but the utilization of these bacteria is limited by their opportunistic pathogenicity to humans. The third replicon of the Bcc, megaplasmid pC3 (0.5 to 1.4 Mb, previously chromosome 3), is important for various phenotypes, including virulence, antifungal, and proteolytic activities and the utilization of certain substrates. Approximately half of plasmid pC3 is well conserved throughout sequenced Bcc members, while the other half is not. To better locate the regions responsible for the key phenotypes, pC3 mutant derivatives of Burkholderia cenocepacia H111 carrying large deletions (up to 0.58 Mb) were constructed with the aid of the FLP-FRT (FRT, flippase recognition target) recombination system from Saccharomyces cerevisiae The conserved region was shown to confer near-full virulence in both Caenorhabditis elegans and Galleria mellonella infection models. Antifungal activity was unexpectedly independent of the part of pC3 bearing a previously identified antifungal gene cluster, while proteolytic activity was dependent on the nonconserved part of pC3, which encodes the ZmpA protease. To investigate to what degree pC3-encoded functions are dependent on chromosomally encoded functions, we transferred pC3 from Burkholderia cenocepacia K56-2 and Burkholderia lata 383 into other pC3-cured Bcc members. We found that although pC3 is highly important for virulence, it was the genetic background of the recipient that determined the pathogenicity level of the hybrid strain. Furthermore, we found that important phenotypes, such as antifungal activity, proteolytic activity, and some substrate utilization capabilities, can be transferred between Bcc members using pC3.IMPORTANCE The Burkholderia cepacia complex (Bcc) is a group of closely related bacteria with great biotechnological potential. Some strains produce potent antifungal compounds and can promote plant growth or degrade environmental pollutants. However, their agricultural potential is limited by their opportunistic pathogenicity, particularly for cystic fibrosis patients. Despite much study, their virulence remains poorly understood. The third replicon, pC3, which is present in all Bcc isolates and is important for pathogenicity, stress resistance, and the production of antifungal compounds, has recently been reclassified from a chromosome to a megaplasmid. In this study, we identified regions on pC3 important for virulence and antifungal activity and investigated the role of the chromosomal background for the function of pC3 by exchanging the megaplasmid between different Bcc members. Our results may open a new avenue for the construction of antifungal but nonpathogenic Burkholderia hybrids. Such strains may have great potential as biocontrol strains for protecting fungus-borne diseases of plant crops.
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31
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Schmid N, Suppiger A, Steiner E, Pessi G, Kaever V, Fazli M, Tolker-Nielsen T, Jenal U, Eberl L. High intracellular c-di-GMP levels antagonize quorum sensing and virulence gene expression in Burkholderia cenocepacia H111. MICROBIOLOGY-SGM 2017; 163:754-764. [PMID: 28463102 DOI: 10.1099/mic.0.000452] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The opportunistic human pathogen Burkholderia cenocepacia H111 uses two chemically distinct signal molecules for controlling gene expression in a cell density-dependent manner: N-acyl-homoserine lactones (AHLs) and cis-2-dodecenoic acid (BDSF). Binding of BDSF to its cognate receptor RpfR lowers the intracellular c-di-GMP level, which in turn leads to differential expression of target genes. In this study we analysed the transcriptional profile of B. cenocepacia H111 upon artificially altering the cellular c-di-GMP level. One hundred and eleven genes were shown to be differentially expressed, 96 of which were downregulated at a high c-di-GMP concentration. Our analysis revealed that the BDSF, AHL and c-di-GMP regulons overlap for the regulation of 24 genes and that a high c-di-GMP level suppresses expression of AHL-regulated genes. Phenotypic analyses confirmed changes in the expression of virulence factors, the production of AHL signal molecules and the biosynthesis of different biofilm matrix components upon altered c-di-GMP levels. We also demonstrate that the intracellular c-di-GMP level determines the virulence of B. cenocepacia to Caenorhabditis elegans and Galleria mellonella.
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Affiliation(s)
- Nadine Schmid
- Institute of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Angela Suppiger
- Institute of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Elisabeth Steiner
- Institute of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Gabriella Pessi
- Institute of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Volkhard Kaever
- Research Core Unit Metabolomics, Hannover Medical School, Hannover, Germany
| | - Mustafa Fazli
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Tim Tolker-Nielsen
- Costerton Biofilm Center, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Urs Jenal
- Focal Area of Infection Biology, Biozentrum, University of Basel, Basel, Switzerland
| | - Leo Eberl
- Institute of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
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32
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Bartell JA, Blazier AS, Yen P, Thøgersen JC, Jelsbak L, Goldberg JB, Papin JA. Reconstruction of the metabolic network of Pseudomonas aeruginosa to interrogate virulence factor synthesis. Nat Commun 2017; 8:14631. [PMID: 28266498 PMCID: PMC5344303 DOI: 10.1038/ncomms14631] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 01/18/2017] [Indexed: 01/13/2023] Open
Abstract
Virulence-linked pathways in opportunistic pathogens are putative therapeutic targets that may be associated with less potential for resistance than targets in growth-essential pathways. However, efficacy of virulence-linked targets may be affected by the contribution of virulence-related genes to metabolism. We evaluate the complex interrelationships between growth and virulence-linked pathways using a genome-scale metabolic network reconstruction of Pseudomonas aeruginosa strain PA14 and an updated, expanded reconstruction of P. aeruginosa strain PAO1. The PA14 reconstruction accounts for the activity of 112 virulence-linked genes and virulence factor synthesis pathways that produce 17 unique compounds. We integrate eight published genome-scale mutant screens to validate gene essentiality predictions in rich media, contextualize intra-screen discrepancies and evaluate virulence-linked gene distribution across essentiality datasets. Computational screening further elucidates interconnectivity between inhibition of virulence factor synthesis and growth. Successful validation of selected gene perturbations using PA14 transposon mutants demonstrates the utility of model-driven screening of therapeutic targets.
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Affiliation(s)
- Jennifer A. Bartell
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Anna S. Blazier
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Phillip Yen
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Juliane C. Thøgersen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Lars Jelsbak
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Joanna B. Goldberg
- Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Children's Healthcare of Atlanta, Atlanta, Georgia 30322, USA
- Emory+Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, Georgia 30322, USA
| | - Jason A. Papin
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
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33
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Burkholderia cepacia Complex Regulation of Virulence Gene Expression: A Review. Genes (Basel) 2017; 8:genes8010043. [PMID: 28106859 PMCID: PMC5295037 DOI: 10.3390/genes8010043] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/11/2017] [Accepted: 01/12/2017] [Indexed: 12/31/2022] Open
Abstract
Burkholderia cepacia complex (Bcc) bacteria emerged as opportunistic pathogens in cystic fibrosis and immunocompromised patients. Their eradication is very difficult due to the high level of intrinsic resistance to clinically relevant antibiotics. Bcc bacteria have large and complex genomes, composed of two to four replicons, with variable numbers of insertion sequences. The complexity of Bcc genomes confers a high genomic plasticity to these bacteria, allowing their adaptation and survival to diverse habitats, including the human host. In this work, we review results from recent studies using omics approaches to elucidate in vivo adaptive strategies and virulence gene regulation expression of Bcc bacteria when infecting the human host or subject to conditions mimicking the stressful environment of the cystic fibrosis lung.
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34
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Shastri S, Spiewak HL, Sofoluwe A, Eidsvaag VA, Asghar AH, Pereira T, Bull EH, Butt AT, Thomas MS. An efficient system for the generation of marked genetic mutants in members of the genus Burkholderia. Plasmid 2016; 89:49-56. [PMID: 27825973 PMCID: PMC5312678 DOI: 10.1016/j.plasmid.2016.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 10/24/2016] [Accepted: 11/04/2016] [Indexed: 12/22/2022]
Abstract
To elucidate the function of a gene in bacteria it is vital that targeted gene inactivation (allelic replacement) can be achieved. Allelic replacement is often carried out by disruption of the gene of interest by insertion of an antibiotic-resistance marker followed by subsequent transfer of the mutant allele to the genome of the host organism in place of the wild-type gene. However, due to their intrinsic resistance to many antibiotics only selected antibiotic-resistance markers can be used in members of the genus Burkholderia, including the Burkholderia cepacia complex (Bcc). Here we describe the construction of improved antibiotic-resistance cassettes that specify resistance to kanamycin, chloramphenicol or trimethoprim effectively in the Bcc and related species. These were then used in combination with and/or to construct a series enhanced suicide vectors, pSHAFT2, pSHAFT3 and pSHAFT-GFP to facilitate effective allelic replacement in the Bcc. Validation of these improved suicide vectors was demonstrated by the genetic inactivation of selected genes in the Bcc species Burkholderia cenocepacia and B. lata, and in the non-Bcc species, B. thailandensis. We have constructed antibiotic-resistance cassettes and suicide vectors for use in Burkholderia and related species. These vectors facilitate construction of mutants by gene disruption with antibiotic-resistance markers. We have validated the utility of the vectors for marked genetic inactivation in members of the genus Burkholderia.
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Affiliation(s)
- Sravanthi Shastri
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK
| | - Helena L Spiewak
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK
| | - Aderonke Sofoluwe
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK
| | - Vigdis A Eidsvaag
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK
| | - Atif H Asghar
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK
| | - Tyrone Pereira
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK
| | - Edward H Bull
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK
| | - Aaron T Butt
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK
| | - Mark S Thomas
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK,.
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35
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Dennis JJ. Burkholderia cenocepacia virulence microevolution in the CF lung: Variations on a theme. Virulence 2016; 8:618-620. [PMID: 27786605 DOI: 10.1080/21505594.2016.1253660] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Jonathan J Dennis
- a Department of Biological Sciences , Centennial Centre for Interdisciplinary Science, University of Alberta , Edmonton, Alberta , Canada
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36
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Moreira AS, Mil-Homens D, Sousa SA, Coutinho CP, Pinto-de-Oliveira A, Ramos CG, Dos Santos SC, Fialho AM, Leitão JH, Sá-Correia I. Variation of Burkholderia cenocepacia virulence potential during cystic fibrosis chronic lung infection. Virulence 2016; 8:782-796. [PMID: 27652671 DOI: 10.1080/21505594.2016.1237334] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
During long-term lung infection in cystic fibrosis (CF) patients, Burkholderia cenocepacia faces multiple selective pressures in this highly stressful and fluctuating environment. As a consequence, the initial infecting strain undergoes genetic changes that result in the diversification of genotypes and phenotypes. Whether this clonal expansion influences the pathogenic potential is unclear. The virulence potential of 39 sequential B. cenocepacia (recA lineage IIIA) isolates, corresponding to 3 different clones retrieved from 3 chronically infected CF patients was compared in this study using the non-mammalian infection hosts Galleria mellonella and Caenorhabditis elegans. The isolates used in this retrospective study were picked randomly from selective agar plates as part of a CF Center routine, from the onset of infection until patients' death after 3.5 and 7.5 y or the more recent isolation date after 12.5 y of chronic infection. The infection models proved useful to assess virulence potential diversification, but for some isolates the relative values diverged in C. elegans and G. mellonella. Results also reinforce the concept of the occurrence of clonal diversification and co-existence of multiple phenotypes within the CF lungs, also with respect to pathogenicity. No clear trend of decrease (or increase) of the virulence potential throughout long-term infection was found but there is an apparent tendency for a clone/patient-dependent decrease of virulence when the G. mellonella model was used. The sole avirulent variant in both infection hosts was found to lack the small third replicon previously associated to virulence. Although possible, the in vivo loss of this nonessential megaplasmid was found to be a rare event (1 among a total of 64 isolates examined).
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Affiliation(s)
- Ana S Moreira
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Dalila Mil-Homens
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Sílvia A Sousa
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Carla P Coutinho
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Ana Pinto-de-Oliveira
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Christian G Ramos
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Sandra C Dos Santos
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Arsénio M Fialho
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Jorge H Leitão
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
| | - Isabel Sá-Correia
- a iBB-Institute for Bioengineering and Biosciences , Department of Bioengineering , Instituto Superior Técnico, Universidade de Lisboa , Lisbon , Portugal
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Depluverez S, Devos S, Devreese B. The Role of Bacterial Secretion Systems in the Virulence of Gram-Negative Airway Pathogens Associated with Cystic Fibrosis. Front Microbiol 2016; 7:1336. [PMID: 27625638 PMCID: PMC5003817 DOI: 10.3389/fmicb.2016.01336] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 08/12/2016] [Indexed: 11/16/2022] Open
Abstract
Cystic fibrosis (CF) is the most common lethal inherited disorder in Caucasians. It is caused by mutation of the CF transmembrane conductance regulator (CFTR) gene. A defect in the CFTR ion channel causes a dramatic change in the composition of the airway surface fluid, leading to a highly viscous mucus layer. In healthy individuals, the majority of bacteria trapped in the mucus layer are removed and destroyed by mucociliary clearance. However, in the lungs of patients with CF, the mucociliary clearance is impaired due to dehydration of the airway surface fluid. As a consequence, patients with CF are highly susceptible to chronic or intermittent pulmonary infections, often causing extensive lung inflammation and damage, accompanied by a decreased life expectancy. This mini review will focus on the different secretion mechanisms used by the major bacterial CF pathogens to release virulence factors, their role in resistance and discusses the potential for therapeutically targeting secretion systems.
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Affiliation(s)
- Sofie Depluverez
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Department of Biochemistry and Microbiology, Ghent University Ghent, Belgium
| | - Simon Devos
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Department of Biochemistry and Microbiology, Ghent University Ghent, Belgium
| | - Bart Devreese
- Laboratory for Protein Biochemistry and Biomolecular Engineering, Department of Biochemistry and Microbiology, Ghent University Ghent, Belgium
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Maldonado RF, Sá-Correia I, Valvano MA. Lipopolysaccharide modification in Gram-negative bacteria during chronic infection. FEMS Microbiol Rev 2016; 40:480-93. [PMID: 27075488 PMCID: PMC4931227 DOI: 10.1093/femsre/fuw007] [Citation(s) in RCA: 350] [Impact Index Per Article: 43.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 08/23/2015] [Accepted: 03/10/2016] [Indexed: 12/16/2022] Open
Abstract
The Gram-negative bacterial lipopolysaccharide (LPS) is a major component of the outer membrane that plays a key role in host-pathogen interactions with the innate immune system. During infection, bacteria are exposed to a host environment that is typically dominated by inflammatory cells and soluble factors, including antibiotics, which provide cues about regulation of gene expression. Bacterial adaptive changes including modulation of LPS synthesis and structure are a conserved theme in infections, irrespective of the type or bacteria or the site of infection. In general, these changes result in immune system evasion, persisting inflammation and increased antimicrobial resistance. Here, we review the modifications of LPS structure and biosynthetic pathways that occur upon adaptation of model opportunistic pathogens (Pseudomonas aeruginosa, Burkholderia cepacia complex bacteria, Helicobacter pylori and Salmonella enterica) to chronic infection in respiratory and gastrointestinal sites. We also discuss the molecular mechanisms of these variations and their role in the host-pathogen interaction.
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Affiliation(s)
- Rita F. Maldonado
- Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon 1049-001, Portugal
| | - Isabel Sá-Correia
- Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon 1049-001, Portugal
| | - Miguel A. Valvano
- Department of Microbiology and Immunology, University of Western Ontario, London, ON N6A 5C1, Canada
- Centre for Infection and Immunity, Queen's University Belfast, Belfast BT9 7BL, UK
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Chu W, McLean RJC. Quorum Signal Inhibitors and Their Potential Use against Fish Diseases. JOURNAL OF AQUATIC ANIMAL HEALTH 2016; 28:91-96. [PMID: 27184419 DOI: 10.1080/08997659.2016.1150907] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Quorum sensing (QS) is a process of bacterial communication used to control group behaviors, including bioluminescence, virulence factor production, biofilm formation, and biofilm antimicrobial tolerance. Many aquatic bacterial pathogens such as Aeromonas, Vibrio, and Edwardsiella spp. use QS to regulate virulence factor production. The disruption of QS has been shown to be an effective strategy in the competition between higher organisms and bacteria and more recently between bacterial species. For this reason, QS disruption has been proposed as a strategy to prevent bacterial pathogenicity. In this review, we summarize the current literature and illustrate the value of QS inhibitors in controlling virulence production in aquatic bacterial pathogens. This represents a new, nonantibiotic strategy to combat fish diseases. Received August 11, 2015; accepted January 26, 2016.
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Affiliation(s)
- Weihua Chu
- a Department of Microbiology , School of Life Science and Technology, China Pharmaceutical University , Nanjing 210009 , China
| | - Robert J C McLean
- b Department of Biology , Texas State University , 601 University Drive, San Marcos , Texas 78666 , USA
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Abstract
In the 1990s several biocontrol agents on that contained Burkholderia strains were registered by the United States Environmental Protection Agency (EPA). After risk assessment these products were withdrawn from the market and a moratorium was placed on the registration of Burkholderia-containing products, as these strains may pose a risk to human health. However, over the past few years the number of novel Burkholderia species that exhibit plant-beneficial properties and are normally not isolated from infected patients has increased tremendously. In this commentary we wish to summarize recent efforts that aim at discerning pathogenic from beneficial Burkholderia strains.
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Affiliation(s)
- Leo Eberl
- Department of Plant and Microbial Biology, University Zürich, Zurich, CH-8008, Switzerland
| | - Peter Vandamme
- Laboratory of Microbiology, Ghent University, Ledeganckstraat 35, B-9000 Gent, Belgium
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41
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Aubert DF, Xu H, Yang J, Shi X, Gao W, Li L, Bisaro F, Chen S, Valvano MA, Shao F. A Burkholderia Type VI Effector Deamidates Rho GTPases to Activate the Pyrin Inflammasome and Trigger Inflammation. Cell Host Microbe 2016; 19:664-74. [PMID: 27133449 DOI: 10.1016/j.chom.2016.04.004] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 03/17/2016] [Accepted: 03/30/2016] [Indexed: 10/21/2022]
Abstract
Burkholderia cenocepacia is an opportunistic pathogen of the cystic fibrosis lung that elicits a strong inflammatory response. B. cenocepacia employs a type VI secretion system (T6SS) to survive in macrophages by disarming Rho-type GTPases, causing actin cytoskeletal defects. Here, we identified TecA, a non-VgrG T6SS effector responsible for actin disruption. TecA and other bacterial homologs bear a cysteine protease-like catalytic triad, which inactivates Rho GTPases by deamidating a conserved asparagine in the GTPase switch-I region. RhoA deamidation induces caspase-1 inflammasome activation, which is mediated by the familial Mediterranean fever disease protein Pyrin. In mouse infection, the deamidase activity of TecA is necessary and sufficient for B. cenocepacia-triggered lung inflammation and also protects mice from lethal B. cenocepacia infection. Therefore, Burkholderia TecA is a T6SS effector that modifies a eukaryotic target through an asparagine deamidase activity, which in turn elicits host cell death and inflammation through activation of the Pyrin inflammasome.
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Affiliation(s)
- Daniel F Aubert
- Department of Microbiology and Immunology, University of Western Ontario, London N6A 5C1, Canada
| | - Hao Xu
- National Institute of Biological Sciences, Beijing 102206, China
| | - Jieling Yang
- National Institute of Biological Sciences, Beijing 102206, China; National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xuyan Shi
- National Institute of Biological Sciences, Beijing 102206, China
| | - Wenqing Gao
- National Institute of Biological Sciences, Beijing 102206, China
| | - Lin Li
- National Institute of Biological Sciences, Beijing 102206, China
| | - Fabiana Bisaro
- Centre for Infection and Immunity, Queen's University Belfast, Belfast BT9 7AE, UK
| | - She Chen
- National Institute of Biological Sciences, Beijing 102206, China
| | - Miguel A Valvano
- Department of Microbiology and Immunology, University of Western Ontario, London N6A 5C1, Canada; Centre for Infection and Immunity, Queen's University Belfast, Belfast BT9 7AE, UK.
| | - Feng Shao
- National Institute of Biological Sciences, Beijing 102206, China; National Institute of Biological Sciences, Beijing, Collaborative Innovation Center for Cancer Medicine, Beijing 102206, China.
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Mathew A, Jenul C, Carlier AL, Eberl L. The role of siderophores in metal homeostasis of members of the genus Burkholderia. ENVIRONMENTAL MICROBIOLOGY REPORTS 2016; 8:103-109. [PMID: 26621188 DOI: 10.1111/1758-2229.12357] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Revised: 11/18/2015] [Accepted: 11/19/2015] [Indexed: 06/05/2023]
Abstract
Although members of the genus Burkholderia can utilize a high-affinity iron uptake system to sustain growth under iron-limiting conditions, many strains also produce siderophores, suggesting that they may serve alternative functions. Here we demonstrate that the two Burkholderia siderophores pyochelin and ornibactin can protect the cells from metal toxicity and thus play an alternative role in metal homeostasis. We also demonstrate that metals such as copper and zinc induce the production of ornibactin.
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Affiliation(s)
- Anugraha Mathew
- Department of Microbiology, Institute of Plant Biology, University of Zurich, Zurich, Switzerland
| | - Christian Jenul
- Department of Microbiology, Institute of Plant Biology, University of Zurich, Zurich, Switzerland
| | - Aurelien L Carlier
- Department of Microbiology, Institute of Plant Biology, University of Zurich, Zurich, Switzerland
| | - Leo Eberl
- Department of Microbiology, Institute of Plant Biology, University of Zurich, Zurich, Switzerland
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Tedesco P, Visone M, Parrilli E, Tutino ML, Perrin E, Maida I, Fani R, Ballestriero F, Santos R, Pinilla C, Di Schiavi E, Tegos G, de Pascale D. Investigating the Role of the Host Multidrug Resistance Associated Protein Transporter Family in Burkholderia cepacia Complex Pathogenicity Using a Caenorhabditis elegans Infection Model. PLoS One 2015; 10:e0142883. [PMID: 26587842 PMCID: PMC4654563 DOI: 10.1371/journal.pone.0142883] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/28/2015] [Indexed: 11/24/2022] Open
Abstract
This study investigated the relationship between host efflux system of the non-vertebrate nematode Caenorhabditis elegans and Burkholderia cepacia complex (Bcc) strain virulence. This is the first comprehensive effort to profile host-transporters within the context of Bcc infection. With this aim, two different toxicity tests were performed: a slow killing assay that monitors mortality of the host by intestinal colonization and a fast killing assay that assesses production of toxins. A Virulence Ranking scheme was defined, that expressed the toxicity of the Bcc panel members, based on the percentage of surviving worms. According to this ranking the 18 Bcc strains were divided in 4 distinct groups. Only the Cystic Fibrosis isolated strains possessed profound nematode killing ability to accumulate in worms’ intestines. For the transporter analysis a complete set of isogenic nematode single Multidrug Resistance associated Protein (MRP) efflux mutants and a number of efflux inhibitors were interrogated in the host toxicity assays. The Bcc pathogenicity profile of the 7 isogenic C. elegans MRP knock-out strains functionality was classified in two distinct groups. Disabling host transporters enhanced nematode mortality more than 50% in 5 out of 7 mutants when compared to wild type. In particular mrp-2 was the most susceptible phenotype with increased mortality for 13 out 18 Bcc strains, whereas mrp-3 and mrp-4 knock-outs had lower mortality rates, suggesting a different role in toxin-substrate recognition. The use of MRP efflux inhibitors in the assays resulted in substantially increased (>40% on average) mortality of wild-type worms.
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Affiliation(s)
- Pietro Tedesco
- Institute of Protein Biochemistry, National Research Council, Via P. Castellino 111, I-80131, Naples, Italy
- Department of Chemical Sciences and School of Biotechnological Sciences, University of Naples Federico II, Via Cintia, I-80126, Naples, Italy
| | - Marco Visone
- Institute of Protein Biochemistry, National Research Council, Via P. Castellino 111, I-80131, Naples, Italy
| | - Ermenegilda Parrilli
- Department of Chemical Sciences and School of Biotechnological Sciences, University of Naples Federico II, Via Cintia, I-80126, Naples, Italy
| | - Maria Luisa Tutino
- Department of Chemical Sciences and School of Biotechnological Sciences, University of Naples Federico II, Via Cintia, I-80126, Naples, Italy
| | - Elena Perrin
- Laboratory of Microbial and Molecular Evolution, Department of Biology, University of Florence, Via Madonna del Piano, I-50019, Sesto Fiorentino, Florence, Italy
| | - Isabel Maida
- Laboratory of Microbial and Molecular Evolution, Department of Biology, University of Florence, Via Madonna del Piano, I-50019, Sesto Fiorentino, Florence, Italy
| | - Renato Fani
- Laboratory of Microbial and Molecular Evolution, Department of Biology, University of Florence, Via Madonna del Piano, I-50019, Sesto Fiorentino, Florence, Italy
| | - Francesco Ballestriero
- School of Biotechnology and Biomolecular Sciences and Centre for Marine Bio-Innovation, University of New South Wales, Sydney, 2052, New South Wales, Australia
| | - Radleigh Santos
- Torrey Pines Institute of Molecular Studies, Port St. Lucie, FL, United States of America, and San Diego, CA, United States of America
| | - Clemencia Pinilla
- Torrey Pines Institute of Molecular Studies, Port St. Lucie, FL, United States of America, and San Diego, CA, United States of America
| | - Elia Di Schiavi
- Institute of Bioscience and BioResources, National Research Council, via P. Castellino 111, I-80131, Naples, Italy
- Institute of Genetics and Biophysics, National Research Council, via P. Castellino 111, I-80131, Naples, Italy
| | - George Tegos
- Torrey Pines Institute of Molecular Studies, Port St. Lucie, FL, United States of America, and San Diego, CA, United States of America
- Wellman Centre for Photomedicine, Massachusetts General Hospital, Boston, MA, United States of America
- Department of Dermatology, Harvard Medical School, Boston, MA, United States of America
- * E-mail: (DdP); (GT)
| | - Donatella de Pascale
- Institute of Protein Biochemistry, National Research Council, Via P. Castellino 111, I-80131, Naples, Italy
- * E-mail: (DdP); (GT)
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44
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Aubert DF, Valvano MA, Hu S. Quantification of type VI secretion system activity in macrophages infected with Burkholderia cenocepacia. Microbiology (Reading) 2015; 161:2161-73. [DOI: 10.1099/mic.0.000174] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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45
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Burkholderia cenocepacia Lipopolysaccharide Modification and Flagellin Glycosylation Affect Virulence but Not Innate Immune Recognition in Plants. mBio 2015; 6:e00679. [PMID: 26045541 PMCID: PMC4462625 DOI: 10.1128/mbio.00679-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
UNLABELLED Burkholderia cenocepacia causes opportunistic infections in plants, insects, animals, and humans, suggesting that "virulence" depends on the host and its innate susceptibility to infection. We hypothesized that modifications in key bacterial molecules recognized by the innate immune system modulate host responses to B. cenocepacia. Indeed, modification of lipopolysaccharide (LPS) with 4-amino-4-deoxy-L-arabinose and flagellin glycosylation attenuates B. cenocepacia infection in Arabidopsis thaliana and Galleria mellonella insect larvae. However, B. cenocepacia LPS and flagellin triggered rapid bursts of nitric oxide and reactive oxygen species in A. thaliana leading to activation of the PR-1 defense gene. These responses were drastically reduced in plants with fls2 (flagellin FLS2 host receptor kinase), Atnoa1 (nitric oxide-associated protein 1), and dnd1-1 (reduced production of nitric oxide) null mutations. Together, our results indicate that LPS modification and flagellin glycosylation do not affect recognition by plant receptors but are required for bacteria to establish overt infection. IMPORTANCE Virulence and pathogenicity are properties ascribed to microbes, which actually require careful consideration of the host. Using the term "pathogen" to define a microbe without considering its host has recently been debated, since the microbe's capacity to establish a niche in a given host is a critical feature associated with infection. Opportunistic bacteria are a perfect example of microbes whose ability to cause disease is intimately related to the host's ability to recognize and respond to the infection. Here, we use the opportunistic bacterium Burkholderia cenocepacia and the host plant Arabidopsis thaliana to investigate the role of bacterial surface molecules, namely, lipopolysaccharide and flagellin, in contributing to infection and also in eliciting a host response. We reveal that both molecules can be modified by glycosylation, and although the modifications are critical for the bacteria to establish an infection, they do not impact the host's ability to recognize the pathogen.
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46
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Franke J, Ishida K, Hertweck C. Plasticity of the Malleobactin Pathway and Its Impact on Siderophore Action in Human Pathogenic Bacteria. Chemistry 2015; 21:8010-4. [DOI: 10.1002/chem.201500757] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Indexed: 12/23/2022]
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47
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In-Frame and Unmarked Gene Deletions in Burkholderia cenocepacia via an Allelic Exchange System Compatible with Gateway Technology. Appl Environ Microbiol 2015; 81:3623-30. [PMID: 25795676 DOI: 10.1128/aem.03909-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 03/11/2015] [Indexed: 02/04/2023] Open
Abstract
Burkholderia cenocepacia is an emerging opportunistic pathogen causing life-threatening infections in immunocompromised individuals and in patients with cystic fibrosis, which are often difficult, if not impossible, to treat. Understanding the genetic basis of virulence in this emerging pathogen is important for the development of novel treatment regimes. Generation of deletion mutations in genes predicted to encode virulence determinants is fundamental to investigating the mechanisms of pathogenesis. However, there is a lack of appropriate selectable and counterselectable markers for use in B. cenocepacia, making its genetic manipulation problematic. Here we describe a Gateway-compatible allelic exchange system based on the counterselectable pheS gene and the I-SceI homing endonuclease. This system provides efficiency in cloning homology regions of target genes and allows the generation of precise and unmarked gene deletions in B. cenocepacia. As a proof of concept, we demonstrate its utility by deleting the Bcam1349 gene, encoding a cyclic di-GMP (c-di-GMP)-responsive regulator protein important for biofilm formation.
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48
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Pribytkova T, Lightly TJ, Kumar B, Bernier SP, Sorensen JL, Surette MG, Cardona ST. The attenuated virulence of aBurkholderia cenocepacia paaABCDEmutant is due to inhibition of quorum sensing by release of phenylacetic acid. Mol Microbiol 2014; 94:522-36. [DOI: 10.1111/mmi.12771] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/20/2014] [Indexed: 01/08/2023]
Affiliation(s)
- Tanya Pribytkova
- Department of Microbiology; University of Manitoba; Winnipeg Manitoba Canada
| | - Tasia Joy Lightly
- Department of Microbiology; University of Manitoba; Winnipeg Manitoba Canada
| | - Brijesh Kumar
- Department of Microbiology; University of Manitoba; Winnipeg Manitoba Canada
| | - Steve P. Bernier
- Department of Medicine; Farncombe Family Digestive Health Research Institute; McMaster University; Hamilton Ontario Canada
| | - John L. Sorensen
- Department of Chemistry; University of Manitoba; Winnipeg Manitoba Canada
| | - Michael G. Surette
- Department of Medicine; Farncombe Family Digestive Health Research Institute; McMaster University; Hamilton Ontario Canada
- Department of Biochemistry and Biological Sciences; McMaster University; Hamilton Ontario Canada
| | - Silvia T. Cardona
- Department of Microbiology; University of Manitoba; Winnipeg Manitoba Canada
- Department of Medical Microbiology & Infectious Disease; University of Manitoba; Winnipeg Manitoba Canada
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49
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Zlosnik JEA, Mori PY, To D, Leung J, Hird TJ, Speert DP. Swimming motility in a longitudinal collection of clinical isolates of Burkholderia cepacia complex bacteria from people with cystic fibrosis. PLoS One 2014; 9:e106428. [PMID: 25203161 PMCID: PMC4159263 DOI: 10.1371/journal.pone.0106428] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 07/29/2014] [Indexed: 12/13/2022] Open
Abstract
Chronic bacterial lung infections in cystic fibrosis (CF) are the leading cause of morbidity and mortality. While a range of bacteria are known to be capable of establishing residence in the CF lung, only a small number have a clearly established link to deteriorating clinical status. The two bacteria with the clearest roles in CF lung disease are Pseudomonas aeruginosa and bacteria belonging to the Burkholderia cepacia complex (BCC). A number of common adaptations by P. aeruginosa strains to chronic lung infection in CF have been well described. Typically, initial isolates of P. aeruginosa are nonmucoid and display a range of putative virulence determinants. Upon establishment of chronic infection, subsequent isolates ultimately show a reduction in putative virulence determinants, including swimming motility, along with an acquisition of the mucoid phenotype and increased levels of antimicrobial resistance. Infections by BCC are marked by an unpredictable, but typically worse, clinical outcome. However, in contrast to P. aeruginosa infections in CF, studies describing adaptive changes in BCC bacterial phenotype during chronic lung infections are far more limited. To further enhance our understanding of chronic lung infections by BCC bacteria in CF, we assessed the swimming motility phenotype in 551 isolates of BCC bacteria from cystic fibrosis (CF) lung infections between 1981 and 2007. These data suggest that swimming motility is not typically lost by BCC during chronic infection, unlike as seen in P. aeruginosa infections. Furthermore, while we observed a statistically significant link between mucoidy and motility, we did not detect any link between motility phenotype and clinical outcome. These studies highlight the need for further work to understand the adaptive changes of BCC bacteria during chronic infection in the CF lung.
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Affiliation(s)
- James E. A. Zlosnik
- Centre for Understanding and Preventing Infection in Children, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
| | - Paul Y. Mori
- Centre for Understanding and Preventing Infection in Children, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Derek To
- Centre for Understanding and Preventing Infection in Children, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - James Leung
- Centre for Understanding and Preventing Infection in Children, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Trevor J. Hird
- Centre for Understanding and Preventing Infection in Children, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - David P. Speert
- Centre for Understanding and Preventing Infection in Children, Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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50
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Williamson D. Approaches to modelling the human immune response in transition of candidates from research to development. J Immunol Res 2014; 2014:395302. [PMID: 24949489 PMCID: PMC4033477 DOI: 10.1155/2014/395302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 03/11/2014] [Indexed: 11/28/2022] Open
Abstract
This review considers the steps required to evaluate a candidate biodefense vaccine or therapy as it emerges from the research phase, in order to transition it to development. The options for preclinical modelling of efficacy are considered in the context of the FDA's Animal Rule.
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Affiliation(s)
- Diane Williamson
- Defence Science and Technology Laboratory (DSTL), Porton Down, Salisbury, Wilts SP4 0JQ, UK
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