1
|
Zafer MM, El Bastawisie MM, Wassef M, Hussein AF, Ramadan MA. Epidemiological features of nosocomial Klebsiella pneumoniae: virulence and resistance determinants. Future Microbiol 2021; 17:27-40. [PMID: 34877876 DOI: 10.2217/fmb-2021-0092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Aim: The authors aimed to examine antibiotic resistance genes and representative virulence determinants among 100 Klebsiella pneumoniae isolates with an emphasis on capsular serotypes and clonality of some of the isolates. Methods: PCR amplification of (rmpA, rmpA2, iutA, iroN and IncHI1B plasmid) and (NDM, OXA-48, KPC, CTX-M-15, VIM, IMP, SPM) was conducted. Wzi sequencing and multilocus sequence typing (MLST) were performed. Results: K2 was the only detected serotype in the authors' collection. RMPA2 was the most common capsule-associated virulence gene detected. All studied isolates harbored OXA-48-like (100%) and NDM (43%) (n = 43). ST147 was the most common sequence type. Conclusion: This work provides insight into the evolution of the coexistence of virulence and resistance genes in a tertiary healthcare setting in Cairo, Egypt.
Collapse
Affiliation(s)
- Mai M Zafer
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ahram Canadian University, Cairo, Egypt
| | - Maha M El Bastawisie
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ahram Canadian University, Cairo, Egypt
| | - Mona Wassef
- Clinical and Chemical Pathology Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Amira Fa Hussein
- Clinical and Chemical Pathology Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Mohammed A Ramadan
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| |
Collapse
|
2
|
Hypervirulent Klebsiella pneumoniae Sequence Type 420 with a Chromosomally Inserted Virulence Plasmid. Int J Mol Sci 2021; 22:ijms22179196. [PMID: 34502111 PMCID: PMC8431375 DOI: 10.3390/ijms22179196] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 08/24/2021] [Indexed: 12/03/2022] Open
Abstract
Background: Klebsiella pneumoniae causes severe diseases including sepsis, pneumonia and wound infections and is differentiated into hypervirulent (hvKp) and classic (cKp) pathotypes. hvKp isolates are characterized clinically by invasive and multiple site infection and phenotypically in particular through hypermucoviscosity and increased siderophore production, enabled by the presence of the respective virulence genes, which are partly carried on plasmids. Methods: Here, we analyzed two K. pneumoniae isolates of a human patient that caused severe multiple site infection. By applying both genomic and phenotypic experiments and combining basic science with clinical approaches, we aimed at characterizing the clinical background as well as the two isolates in-depth. This also included bioinformatics analysis of a chromosomal virulence plasmid integration event. Results: Our genomic analysis revealed that the two isolates were clonal and belonged to sequence type 420, which is not only the first description of this K. pneumoniae subtype in Germany but also suggests belonging to the hvKp pathotype. The latter was supported by the clinical appearance and our phenotypic findings revealing increased siderophore production and hypermucoviscosity similar to an archetypical, hypervirulent K. pneumoniae strain. In addition, our in-depth bioinformatics analysis suggested the insertion of a hypervirulence plasmid in the bacterial chromosome, mediated by a new IS5 family sub-group IS903 insertion sequence designated ISKpn74. Conclusion: Our study contributes not only to the understanding of hvKp and the association between hypervirulence and clinical outcomes but reveals the chromosomal integration of a virulence plasmid, which might lead to tremendous public health implications.
Collapse
|
3
|
Matanza XM, López-Suárez L, do Vale A, Osorio CR. The two-component system RstAB regulates production of a polysaccharide capsule with a role in virulence in the marine pathogen Photobacterium damselae subsp. damselae. Environ Microbiol 2021; 23:4859-4880. [PMID: 34423883 DOI: 10.1111/1462-2920.15731] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 06/23/2021] [Accepted: 07/21/2021] [Indexed: 12/29/2022]
Abstract
The marine bacterium Photobacterium damselae subsp. damselae (Pdd) causes disease in marine animals and humans. Previous studies demonstrated that mutation of the two-component system RstAB strongly impacts virulence of this pathogen, but the RstAB regulon has not been thoroughly elucidated. We here compared the transcriptomes of Pdd RM-71 and ΔrstA and ΔrstB derivatives using RNA-seq. In accordance with previous studies, RstAB positively regulated cytotoxins Dly, PhlyP and PhlyC. This analysis also demonstrated a positive regulation of outer membrane proteins, resistance against antimicrobials and potential virulence factors by this system. Remarkably, RstAB positively regulated two hitherto uncharacterised gene clusters involved in the synthesis of a polysaccharide capsule. Presence of a capsular layer in wild-type cells was confirmed by transmission electron microscopy, whereas rstA and rstB mutants were non-capsulated. Mutants for capsule synthesis genes, wza and wzc exhibited acapsular phenotypes, were impaired in resistance against the bactericidal action of fish serum and mucus, and were strongly impaired in virulence for fish, indicating a major role of capsule in virulence. Collectively, this study demonstrates that RstAB is a major positive regulator of key virulence factors including a polysaccharide capsule essential for full virulence in a pathogenic Photobacterium.
Collapse
Affiliation(s)
- Xosé M Matanza
- Departamento de Microbioloxía e Parasitoloxía, Instituto de Acuicultura, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Laura López-Suárez
- Departamento de Microbioloxía e Parasitoloxía, Instituto de Acuicultura, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Ana do Vale
- Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.,i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Carlos R Osorio
- Departamento de Microbioloxía e Parasitoloxía, Instituto de Acuicultura, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| |
Collapse
|
4
|
Niu T, Guo L, Luo Q, Zhou K, Yu W, Chen Y, Huang C, Xiao Y. Wza gene knockout decreases Acinetobacter baumannii virulence and affects Wzy-dependent capsular polysaccharide synthesis. Virulence 2021; 11:1-13. [PMID: 31878839 PMCID: PMC6961727 DOI: 10.1080/21505594.2019.1700659] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
To investigate the virulence of capsular polysaccharide export protein (Wza) in carbapenem-resistant Acinetobacter baumannii and its effect on capsule formation. wza gene knockout and complementation strains were constructed, and changes in bacterial virulence were observed using in vitro adhesion, antiserum complement killing, anti-oxidation experiments, and infections in Galleria mellonella and mice. The effect of wza knockout on the genes wzb and wzc and wzi were assessed by RT-PCR. We successfully constructed wza knockout and complementation strains. Compared with wild-type (WT) strains, wza knockout strains displayed lower adhesion to A549 cells (p = 0.044), lower antiserum complement killing ability (p = 0.001), and lower mortality of G. mellonella (p = 0.010) and mice (p = 0.033). Expression levels of wzb, wzc and wzi were decreased in wza knockout strains. The antioxidant capacity of Wza knockout bacteria was only slightly decreased. Complementation of the wza gene returned the adhesion ability, antiserum complement killing ability, and mortality of G. mellonella and mice to WT levels. Expression of wzb, wzc and wzi was also returned to WT levels following wza complementation. The results clearly demonstrate that Wza is toxic. Wza affects the expression of other proteins of the Wzy capsule polysaccharide synthesis pathway, which affects the assembly, export, and extracellular fixation of capsular polysaccharide, resulting in synergistic effects that decrease bacterial virulence.
Collapse
Affiliation(s)
- Tianshui Niu
- Collaborative Initiative Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis & Treatment of Infectious Diseases, the First Affiliated Hospital, college of Medicine, Zhejiang University, Hangzhou, China.,Hangzhou Red Cross Hospital/Zhe Jiang Chinese Medcine and Western Medcine Integrated Hospital, Hangzhou, China
| | - Lihua Guo
- Collaborative Initiative Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis & Treatment of Infectious Diseases, the First Affiliated Hospital, college of Medicine, Zhejiang University, Hangzhou, China
| | - Qixia Luo
- Collaborative Initiative Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis & Treatment of Infectious Diseases, the First Affiliated Hospital, college of Medicine, Zhejiang University, Hangzhou, China
| | - Kai Zhou
- Collaborative Initiative Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis & Treatment of Infectious Diseases, the First Affiliated Hospital, college of Medicine, Zhejiang University, Hangzhou, China
| | - Wei Yu
- Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China
| | - Yunbo Chen
- Collaborative Initiative Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis & Treatment of Infectious Diseases, the First Affiliated Hospital, college of Medicine, Zhejiang University, Hangzhou, China
| | - Chen Huang
- Collaborative Initiative Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis & Treatment of Infectious Diseases, the First Affiliated Hospital, college of Medicine, Zhejiang University, Hangzhou, China
| | - Yonghong Xiao
- Collaborative Initiative Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis & Treatment of Infectious Diseases, the First Affiliated Hospital, college of Medicine, Zhejiang University, Hangzhou, China
| |
Collapse
|
5
|
Chiarelli A, Cabanel N, Rosinski-Chupin I, Zongo PD, Naas T, Bonnin RA, Glaser P. Diversity of mucoid to non-mucoid switch among carbapenemase-producing Klebsiella pneumoniae. BMC Microbiol 2020; 20:325. [PMID: 33109078 PMCID: PMC7590720 DOI: 10.1186/s12866-020-02007-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 10/12/2020] [Indexed: 11/10/2022] Open
Abstract
Background Klebsiella pneumoniae is a leading cause of intractable hospital-acquired multidrug-resistant infections and carbapenemase-producing K. pneumoniae (CPKp) are particularly feared. Most of the clinical isolates produce capsule as a major virulence factor. Recombination events at the capsule locus are frequent and responsible for capsule diversity within Klebsiella spp. Capsule diversity may also occur within clonal bacterial populations generating differences in colony aspect. However, little is known about this phenomenon of phenotypic variation in CPKp and its consequences. Results Here, we explored the genetic causes of in vitro switching from capsulated, mucoid to non-mucoid, non-capsulated phenotype in eight clinical CPKp isolates. We compared capsulated, mucoid colony variants with one of their non-capsulated, non-mucoid isogenic variant. The two colony variants were distinguished by their appearance on solid medium. Whole genome comparison was used to infer mutations causing phenotypic differences. The frequency of phenotypic switch was strain-dependent and increased along with colony development on plate. We observed, for 72 non-capsulated variants that the loss of the mucoid phenotype correlates with capsule deficiency and diverse genetic events, including transposition of insertion sequences or point mutations, affecting genes belonging to the capsule operon. Reduced or loss of capsular production was associated with various in vitro phenotypic changes, affecting susceptibility to carbapenem but not to colistin, in vitro biofilm formation and autoaggregation. Conclusions The different impact of the phenotypic variation among the eight isolates in terms of capsule content, biofilm production and carbapenem susceptibility suggested heterogeneous selective advantage for capsular loss according to the strain and the mutation. Based on our results, we believe that attention should be paid in the phenotypic characterization of CPKp clinical isolates, particularly of traits related to virulence and carbapenem resistance. Supplementary information Supplementary information accompanies this paper at 10.1186/s12866-020-02007-y.
Collapse
Affiliation(s)
- Adriana Chiarelli
- EERA Unit "Ecology and Evolution of Antibiotic Resistance", Institut Pasteur - Assistance Publique/Hôpitaux de Paris - University Paris-Saclay, Paris, France.,UMR CNRS 3525, 75015, Paris, France.,Sorbonne Université, 75015, Paris, France
| | - Nicolas Cabanel
- EERA Unit "Ecology and Evolution of Antibiotic Resistance", Institut Pasteur - Assistance Publique/Hôpitaux de Paris - University Paris-Saclay, Paris, France.,UMR CNRS 3525, 75015, Paris, France
| | - Isabelle Rosinski-Chupin
- EERA Unit "Ecology and Evolution of Antibiotic Resistance", Institut Pasteur - Assistance Publique/Hôpitaux de Paris - University Paris-Saclay, Paris, France.,UMR CNRS 3525, 75015, Paris, France
| | - Pengdbamba Dieudonné Zongo
- EERA Unit "Ecology and Evolution of Antibiotic Resistance", Institut Pasteur - Assistance Publique/Hôpitaux de Paris - University Paris-Saclay, Paris, France.,UMR CNRS 3525, 75015, Paris, France
| | - Thierry Naas
- EERA Unit "Ecology and Evolution of Antibiotic Resistance", Institut Pasteur - Assistance Publique/Hôpitaux de Paris - University Paris-Saclay, Paris, France.,EA 7361 Structure, dynamic, function and expression of broad-spectrum beta-lactamases", Faculty of Medicine University Paris-Sud, University Paris-Saclay, Associated French National Reference Center for Antibiotic Resistance: Carbapenemase-producing Enterobacteriaceae, Le Kremlin-Bicêtre, France
| | - Rémy A Bonnin
- EERA Unit "Ecology and Evolution of Antibiotic Resistance", Institut Pasteur - Assistance Publique/Hôpitaux de Paris - University Paris-Saclay, Paris, France.,EA 7361 Structure, dynamic, function and expression of broad-spectrum beta-lactamases", Faculty of Medicine University Paris-Sud, University Paris-Saclay, Associated French National Reference Center for Antibiotic Resistance: Carbapenemase-producing Enterobacteriaceae, Le Kremlin-Bicêtre, France
| | - Philippe Glaser
- EERA Unit "Ecology and Evolution of Antibiotic Resistance", Institut Pasteur - Assistance Publique/Hôpitaux de Paris - University Paris-Saclay, Paris, France. .,UMR CNRS 3525, 75015, Paris, France.
| |
Collapse
|
6
|
Gao Q, Shen Z, Qin J, Liu Y, Li M. Antimicrobial Resistance and Pathogenicity Determination of Community-Acquired Hypervirulent Klebsiella pneumoniae. Microb Drug Resist 2020; 26:1195-1200. [PMID: 32354302 DOI: 10.1089/mdr.2019.0439] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Qianqian Gao
- Department of Laboratory Medicine, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
- Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Zhen Shen
- Department of Laboratory Medicine, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Juanxiu Qin
- Department of Laboratory Medicine, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Yao Liu
- Department of Laboratory Medicine, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Min Li
- Department of Laboratory Medicine, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| |
Collapse
|
7
|
Choby JE, Howard-Anderson J, Weiss DS. Hypervirulent Klebsiella pneumoniae - clinical and molecular perspectives. J Intern Med 2020; 287:283-300. [PMID: 31677303 PMCID: PMC7057273 DOI: 10.1111/joim.13007] [Citation(s) in RCA: 270] [Impact Index Per Article: 67.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/24/2019] [Accepted: 10/01/2019] [Indexed: 12/29/2022]
Abstract
Hypervirulent Klebsiella pneumoniae (hvKp) has emerged as a concerning global pathogen. hvKp is more virulent than classical K. pneumoniae (cKp) and capable of causing community-acquired infections, often in healthy individuals. hvKp is carried in the gastrointestinal tract, which contributes to its spread in the community and healthcare settings. First recognized in Asia, hvKp arose as a leading cause of pyogenic liver abscesses. In the decades since, hvKp has spread globally and causes a variety of infections. In addition to liver abscesses, hvKp is distinct from cKp in its ability to metastasize to distant sites, including most commonly the eye, lung and central nervous system (CNS). hvKp has also been implicated in primary extrahepatic infections including bacteremia, pneumonia and soft tissue infections. The genetic determinants of hypervirulence are often found on large virulence plasmids as well as chromosomal mobile genetic elements which can be used as biomarkers to distinguish hvKp from cKp clinical isolates. These distinct virulence determinants of hvKp include up to four siderophore systems for iron acquisition, increased capsule production, K1 and K2 capsule types, and the colibactin toxin. Additionally, hvKp strains demonstrate hypermucoviscosity, a phenotypic description of hvKp in laboratory conditions that has become a distinguishing feature of many hypervirulent isolates. Alarmingly, multidrug-resistant hypervirulent strains have emerged, creating a new challenge in combating this already dangerous pathogen.
Collapse
Affiliation(s)
- J E Choby
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA.,Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA, USA.,Yerkes National Primate Research Center, Emory University School of Medicine, Atlanta, GA, USA
| | - J Howard-Anderson
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - D S Weiss
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA.,Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA, USA.,Yerkes National Primate Research Center, Emory University School of Medicine, Atlanta, GA, USA.,Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA.,Research Service, Atlanta VA Medical Center, Decatur, GA, USA
| |
Collapse
|
8
|
Lee H, Shin J, Chung YJ, Baek JY, Chung DR, Peck KR, Song JH, Ko KS. Evolution of Klebsiella pneumoniae with mucoid and non-mucoid type colonies within a single patient. Int J Med Microbiol 2019; 309:194-198. [PMID: 30885571 DOI: 10.1016/j.ijmm.2019.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 02/20/2019] [Accepted: 03/04/2019] [Indexed: 12/17/2022] Open
Abstract
We obtained nine Klebsiella pneumoniae isolates successively isolated from a single patient. Four pairs (M1-M4 and NM1-NM4) obtained simultaneously from the same site showed different colony types, mucoid and non-mucoid, while the final isolate (M5) was isolated alone from the blood and showed a mucoid phenotype. The whole genome of isolate M5 was sequenced de novo using the PacBio RSII system, while the others were sequenced with an Illumina Hiseq4000 and mapped to the genome sequences of M5. To identify insertions or deletions in the cps locus, we amplified and sequenced cps locus genes. We identified insertion sequence (IS) elements in several genes of the cps locus or one amino acid substitution in WcaJ in all non-mucoid isolates. Five additional amino acid alterations in RpsJ, LolE, Lon-2, PpsE, and a hypothetical protein were detected in some mucoid and non-mucoid isolates. Based on the genome data and cps locus sequences, the mucoid phenotype may have been lost or converted into the non-mucoid phenotype because of the insertion of IS elements or amino acid alterations at this locus. We inferred a within-host evolutionary scenario, in which non-mucoid variants emerged repeatedly from mucoid isolates, but may be short-lived because of their low fitness.
Collapse
Affiliation(s)
- Haejeong Lee
- Department of Molecular Cell Biology and Samsung Medical Center, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea
| | - Juyoun Shin
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Yeun-Jun Chung
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea; Precision Medicine Research Center, Integrated Research Center for Genome Polymorphism, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Jin Yang Baek
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06351, Republic of Korea
| | - Doo Ryeon Chung
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06351, Republic of Korea; Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
| | - Kyong Ran Peck
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
| | - Jae-Hoon Song
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06351, Republic of Korea
| | - Kwan Soo Ko
- Department of Molecular Cell Biology and Samsung Medical Center, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea; Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06351, Republic of Korea.
| |
Collapse
|
9
|
Lee H, Baek JY, Kim SY, Jo H, Kang K, Ko JH, Cho SY, Chung DR, Peck KR, Song JH, Ko KS. Comparison of virulence between matt and mucoid colonies of Klebsiella pneumoniae coproducing NDM-1 and OXA-232 isolated from a single patient. J Microbiol 2018; 56:665-672. [PMID: 30141159 DOI: 10.1007/s12275-018-8130-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 05/09/2018] [Accepted: 05/24/2018] [Indexed: 12/22/2022]
Abstract
Nine Klebsiella pneumoniae isolates coproducing NDM-1 and OXA-232 carbapenemases were successively isolated from a single patient. Although they were isolated simultaneously and were isogenic, they presented different colony phenotypes (matt and mucoid). All nine isolates were resistant to most antibiotics except colistin and fosfomycin. In addition, matt-type isolates were resistant to tigecycline. No differences were detected in the cps cluster sequences, except for the insertion of IS5 in the wzb gene of two matt-type isolates. In vitro virulence assays based on production of capsular polysaccharide, biofilm formation, and resistance to human serum indicated that the mucoid-type isolates were significantly more virulent than the matt-type. In addition, mucoid-type isolates showed higher survival rates than the matt-type ones in infection experiments in the fruit fly, suggesting a higher virulence of K. pneumoniae isolates with a mucoid phenotype. To our knowledge, this is the first report of K. pneumoniae colonies with different phenotypes being isolated from the same sample. In addition, we show that virulence varies with colony phenotype. Dissemination of K. pneumoniae isolates expressing both antibiotic resistance and high virulence would constitute a great threat.
Collapse
Affiliation(s)
- Haejeong Lee
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea
| | - Jin Yang Baek
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, 06367, Republic of Korea
| | - So Yeon Kim
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea
| | - HyunJi Jo
- Department of Anatomy and Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea
| | - KyeongJin Kang
- Department of Anatomy and Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea
| | - Jae-Hoon Ko
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Sun Young Cho
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Doo Ryeon Chung
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, 06367, Republic of Korea
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Kyong Ran Peck
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Jae-Hoon Song
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, 06367, Republic of Korea
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea
| | - Kwan Soo Ko
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea.
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, 06367, Republic of Korea.
| |
Collapse
|
10
|
Rhinoscleroma pathogenesis: The type K3 capsule of Klebsiella rhinoscleromatis is a virulence factor not involved in Mikulicz cells formation. PLoS Negl Trop Dis 2018; 12:e0006201. [PMID: 29381692 PMCID: PMC5806929 DOI: 10.1371/journal.pntd.0006201] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 02/09/2018] [Accepted: 12/31/2017] [Indexed: 12/16/2022] Open
Abstract
Rhinoscleroma is a human specific chronic granulomatous infection of the nose and upper airways caused by the Gram-negative bacterium Klebsiella pneumoniae subsp. rhinoscleromatis. Although considered a rare disease, it is endemic in low-income countries where hygienic conditions are poor. A hallmark of this pathology is the appearance of atypical foamy monocytes called Mikulicz cells. However, the pathogenesis of rhinoscleroma remains poorly investigated. Capsule polysaccharide (CPS) is a prominent virulence factor in bacteria. All K. rhinoscleromatis strains are of K3 serotype, suggesting that CPS can be an important driver of rhinoscleroma disease. In this study, we describe the creation of the first mutant of K. rhinoscleromatis, inactivated in its capsule export machinery. Using a murine model recapitulating the formation of Mikulicz cells in lungs, we observed that a K. rhinoscleromatis CPS mutant (KR cps-) is strongly attenuated and that mice infected with a high dose of KR cps- are still able to induce Mikulicz cells formation, unlike a K. pneumoniae capsule mutant, and to partially recapitulate the characteristic strong production of IL-10. Altogether, the results of this study show that CPS is a virulence factor of K. rhinoscleromatis not involved in the specific appearance of Mikulicz cells.
Collapse
|
11
|
Ko KS. The contribution of capsule polysaccharide genes to virulence of Klebsiella pneumoniae. Virulence 2016; 8:485-486. [PMID: 27715471 DOI: 10.1080/21505594.2016.1240862] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Kwan Soo Ko
- a Department of Molecular Cell Biology , Sungkyunkwan University School of Medicine , Suwon , Korea
| |
Collapse
|