1
|
Chan YX, Cao H, Jiang S, Li X, Fung KK, Lee CH, Sridhar S, Chen JHK, Ho PL. Genomic investigation of Lactococcus formosensis, Lactococcus garvieae, and Lactococcus petauri reveals differences in species distribution by human and animal sources. Microbiol Spectr 2024; 12:e0054124. [PMID: 38687062 DOI: 10.1128/spectrum.00541-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 04/16/2024] [Indexed: 05/02/2024] Open
Abstract
Lactococcus garvieae is a fish pathogen that can cause diseases in humans and cows. Two genetically related species, Lactococcus formosensis and Lactococcus petauri, may be misidentified as L. garvieae. It is unclear if these species differ in host specificity and virulence genes. This study analyzed the genomes of 120 L. petauri, 53 L. formosensis, and 39 L. garvieae isolates from various sources. The genetic diversity and virulence gene content of these isolates were compared. The results showed that 77 isolates previously reported as L. garvieae were actually L. formosensis or L. petauri. The distribution of the three species varied across different collection sources, with L. petauri being predominant in human infections, human fecal sources, and rainbow trout, while L. formosensis was more common in bovine isolates. The genetic diversity of isolates within each species was high and similar. Using a genomic clustering method, L. petauri, L. formosensis, and L. garvieae were divided into 45, 22, and 13 clusters, respectively. Most rainbow trout and human isolates of L. petauri belonged to different clusters, while L. formosensis isolates from bovine and human sources were also segregated into separate clusters. In L. garvieae, most human isolates were grouped into three clusters that also included isolates from food or other sources. Non-metric multidimensional scaling ordination revealed the differential association of 15 virulence genes, including 14 adherence genes and a bile salt hydrolase gene, with bacterial species and certain collection sources. In conclusion, this work provides evidence of host specificity among the three species. IMPORTANCE Lactococcus formosensis and Lactococcus petauri are two newly discovered bacteria, which are closely related to Lactococcus garvieae, a pathogen that affects farmed rainbow trout, as well as causes cow mastitis and human infections. It is unclear whether the three bacteria differ in their host preference and the presence of genes that contribute to the development of disease. This study shows that L. formosensis and L. petauri were commonly misidentified as L. garvieae. The three bacteria showed different distribution patterns across various sources. L. petauri was predominantly found in human infections and rainbow trout, while L. formosensis was more commonly detected in cow mastitis. Fifteen genes displayed a differential distribution among the three bacteria from certain sources, indicating a genetic basis for the observed host preference. This work indicates the importance of differentiating the three bacteria in diagnostic laboratories for surveillance and outbreak investigation purposes.
Collapse
Affiliation(s)
- You-Xiang Chan
- Department of Microbiology, University of Hong Kong, Hong Kong, China
| | - Huiluo Cao
- Department of Microbiology, University of Hong Kong, Hong Kong, China
| | - Shuo Jiang
- Department of Microbiology, University of Hong Kong, Hong Kong, China
| | - Xin Li
- Department of Microbiology, University of Hong Kong, Hong Kong, China
- Carol Yu Centre for Infection, University of Hong Kong, Hong Kong, China
- Department of Microbiology, Queen Mary Hospital, Hospital Authority, Hong Kong, China
| | - Ka-Kin Fung
- Department of Clinical Pathology, Pamela Youde Nethersole Eastern Hospital, Hospital Authority, Hong Kong, China
| | - Chung-Ho Lee
- Department of Clinical Pathology, Kwong Wah Hospital, Hospital Authority, Hong Kong, China
| | - Siddharth Sridhar
- Department of Microbiology, University of Hong Kong, Hong Kong, China
- Carol Yu Centre for Infection, University of Hong Kong, Hong Kong, China
- Department of Microbiology, Queen Mary Hospital, Hospital Authority, Hong Kong, China
| | | | - Pak-Leung Ho
- Department of Microbiology, University of Hong Kong, Hong Kong, China
- Carol Yu Centre for Infection, University of Hong Kong, Hong Kong, China
- Department of Microbiology, Queen Mary Hospital, Hospital Authority, Hong Kong, China
| |
Collapse
|
2
|
Kobayashi J, Ohkusu M, Matsumoto T, Kubota N, Ishiwada N. Bacteriological and molecular characterization of temperature- and CO 2-dependent Streptococcus pneumoniae serotype 24F ST162 isolated from Japanese children. Microbiol Spectr 2023; 11:e0216523. [PMID: 37823633 PMCID: PMC10714769 DOI: 10.1128/spectrum.02165-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 09/06/2023] [Indexed: 10/13/2023] Open
Abstract
IMPORTANCE We characterized Streptococcus pneumoniae serotype 24F sequence type (ST) 162 isolated from Japanese children with invasive pneumococcal disease (IPD). Owing to its highly invasive nature, serotype 24F is expected to be isolated from clinically significant cases. Serotype 24F ST162 isolates tested in the present study did not grow at 35°C in ambient air. Therefore, antimicrobial susceptibility testing using the broth microdilution method, which is usually conducted in ambient air, cannot be performed, posing a clinical challenge. Clinical practitioners and laboratory personnel should be aware of the epidemiological, bacteriological, and molecular characteristics of serotype 24F ST162. We believe that our findings can help diagnose and treat IPD caused by serotype 24F ST162, a serotype expected to become problematic in the post-13 valent pneumococcal conjugate vaccine era.
Collapse
Affiliation(s)
- Jun Kobayashi
- Department of Laboratory Medicine, Nagano Children’s Hospital, Azumino, Japan
- Life Science Research Center, Nagano Children’s Hospital, Azumino, Japan
| | - Misako Ohkusu
- Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Takehisa Matsumoto
- Department of Laboratory Sciences, Gunma University Graduate School of Health Sciences, Maebashi, Japan
| | - Noriko Kubota
- Department of Laboratory Medicine, Nagano Children’s Hospital, Azumino, Japan
- Life Science Research Center, Nagano Children’s Hospital, Azumino, Japan
| | - Naruhiko Ishiwada
- Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, Japan
| |
Collapse
|
3
|
Abdul Rahman NA, Mohd Desa MN, Masri SN, Taib NM, Sulaiman N, Hazman H, John J. The Molecular Approaches and Challenges of Streptococcus pneumoniae Serotyping for Epidemiological Surveillance in the Vaccine Era. Pol J Microbiol 2023; 72:103-115. [PMID: 37314355 DOI: 10.33073/pjm-2023-023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 05/09/2023] [Indexed: 06/15/2023] Open
Abstract
Streptococcus pneumoniae (pneumococcus) belongs to the Gram-positive cocci. This bacterium typically colonizes the nasopharyngeal region of healthy individuals. It has a distinct polysaccharide capsule - a virulence factor allowing the bacteria to elude the immune defense mechanisms. Consequently, it might trigger aggressive conditions like septicemia and meningitis in immunocompromised or older individuals. Moreover, children below five years of age are at risk of morbidity and mortality. Studies have found 101 S. pneumoniae capsular serotypes, of which several correlate with clinical and carriage isolates with distinct disease aggressiveness. Introducing pneumococcal conjugate vaccines (PCV) targets the most common disease-associated serotypes. Nevertheless, vaccine selection pressure leads to replacing the formerly dominant vaccine serotypes (VTs) by non-vaccine types (NVTs). Therefore, serotyping must be conducted for epidemiological surveillance and vaccine assessment. Serotyping can be performed using numerous techniques, either by the conventional antisera-based (Quellung and latex agglutination) or molecular-based approaches (sequetyping, multiplex PCR, real-time PCR, and PCR-RFLP). A cost-effective and practical approach must be used to enhance serotyping accuracy to monitor the prevalence of VTs and NVTs. Therefore, dependable pneumococcal serotyping techniques are essential to precisely monitor virulent lineages, NVT emergence, and genetic associations of isolates. This review discusses the principles, associated benefits, and drawbacks of the respective available conventional and molecular approaches, and potentially the whole genome sequencing (WGS) to be directed for future exploration.
Collapse
Affiliation(s)
- Nurul Asyikin Abdul Rahman
- 1Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia
- 2School of Biology, Faculty of Applied Sciences, Universiti Teknologi MARA, Kuala Pilah, Malaysia
| | - Mohd Nasir Mohd Desa
- 1Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - Siti Norbaya Masri
- 3Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - Niazlin Mohd Taib
- 3Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - Nurshahira Sulaiman
- 1Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - Hazmin Hazman
- 1Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - James John
- 4Department of Medical Laboratory Technology, School of Allied Health Science, Sathyabama Institute of Science and Technology, Chennai, India
| |
Collapse
|
4
|
Ohkusu M, Takeshita K, Takeuchi N, Ishiwada N. Increase in prevalence of Streptococcus pneumoniae serogroup 24 in children upon introducing 13-valent pneumococcal conjugate vaccine in Japan. Access Microbiol 2023; 5:000507.v3. [PMID: 37091738 PMCID: PMC10118250 DOI: 10.1099/acmi.0.000507.v3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 02/03/2023] [Indexed: 03/18/2023] Open
Abstract
After introducing the 13-valent pneumococcal conjugate vaccine (PCV13) for children, a change in the prevalence of different
Streptococcus pneumoniae
serotypes that cause invasive pneumococcal diseases (IPDs) has been observed. The prevalence of vaccine serotypes has decreased and that of non-vaccine serotypes has increased. Currently, serogroup 24 has become one of the major non-vaccine serotypes causing IPDs in children in Japan. The aim of this study was to characterize clinical and genomic features of
S. pneumoniae
serogroup 24 strains isolated from sterile body sites in Japanese children. Serotyping, multi-locus sequence typing and genomic analysis of capsular polysaccharides of 61 strains of serogroup 24 were performed from 2015 to 2021. Among the 61 strains, 36, 23 and two belonged to serotypes 24F, 24B and 24C, respectively. The 24F sequence type (ST) 2572 and 24B ST 2572 were the major serotypes and sequence types observed from 2015 to 2019. By contrast, 24F ST 162 and 24B ST 2754 were the two major serotypes and sequence types observed after 2020. Two strains of serotype 24C were detected for the first time in Japan. Sequence analysis of the abpA gene, which plays a role in the synthesis of capsular polysaccharides in
S. pneumoniae
, was performed to distinguish different strains of serogroup 24. After the introduction of PCV13 in Japan, serogroup 24 has become one of the most prevalent non-vaccine serotypes causing IPDs in children. This serogroup has not been targeted in the next-generation pneumococcal conjugate vaccines. Therefore, monitoring of
S. pneumoniae
serogroup 24 that causes IPDs in children is essential.
Collapse
Affiliation(s)
- Misako Ohkusu
- Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
| | - Kenichi Takeshita
- Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
| | - Noriko Takeuchi
- Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
| | - Naruhiko Ishiwada
- Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
- *Correspondence: Naruhiko Ishiwada,
| |
Collapse
|
5
|
Comprehensive investigation of antibiotic resistance gene content in cfiA-harboring Bacteroides fragilis isolates of human and animal origins by whole genome sequencing. Int J Med Microbiol 2022; 312:151559. [PMID: 35961233 DOI: 10.1016/j.ijmm.2022.151559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 06/18/2022] [Accepted: 08/07/2022] [Indexed: 11/24/2022] Open
Abstract
INTRODUCTION The emergence of multidrug resistance in Bacteroides fragilis, especially the phylogenetic lineage carrying the carbapenemase gene cfiA, represents an increasing threat to human health. However, knowledge on the diversity of the multidrug-resistant strains and the genetic elements carrying the antibiotic resistance genes (ARGs) remains limited. AIM The objective of the study was to describe the resistome in cfiA-positive B. fragilis. METHODS A collection of cfiA-positive B. fragilis from diverse human (8 bacteremias, 15 wound infections) and animal (2 chickens, 2 pigs, 6 dogs, 3 cats) sources in Hong Kong, 2015-2017 was analysed by whole genome sequencing. RESULTS In the 36 isolates, 13 distinct ARGs (total number 83, median 2, range 0-7 per isolate) other than cfiA were detected. ARGs encoding resistance to aminoglycosides, β-lactams, macrolides, sulphonamides and tetracyclines were carried by CTn341-like, CTnHyb-like, Tn5220-like, Tn4555-like and Tn613-like transposons and were detected in phylogenetically diverse isolates of different host sources. Only few ARGs encoding resistance to metronidazole and tetracyclines were localized on plasmids. In two chicken isolates, a novel transposon (designated as Tn6994) was found to be involved in the dissemination of multiple ARGs mediating resistance to multiple antibiotics, including metronidazole and linezolid that are critically important for treatment of anaerobic infections. In mating experiments, Tn6994 and the associated phenotypic resistance could be transferred to Bacteroides nordii recipient. CONCLUSION This study illustrates the importance of transposons in the dissemination of ARGs in the cfiA-positive division of B. fragilis. One Health approach is necessary to track the dissemination of ARGs.
Collapse
|