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Liang Q, Chen N, Wang W, Zhang B, Luo J, Zhong Y, Zhang F, Zhang Z, Martín-Rodríguez AJ, Wang Y, Xiang L, Xiong X, Hu R, Zhou Y. Co-occurrence of ST412 Klebsiella pneumoniae isolates with hypermucoviscous and non-mucoviscous phenotypes in a short-term hospitalized patient. mSystems 2024:e0026224. [PMID: 38904378 DOI: 10.1128/msystems.00262-24] [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: 02/27/2024] [Accepted: 05/10/2024] [Indexed: 06/22/2024] Open
Abstract
Hypermucoviscosity (HMV) is a phenotype that is commonly associated with hypervirulence in Klebsiella pneumoniae. The factors that contribute to the emergence of HMV subpopulations remain unclear. In this study, eight K. pneumoniae strains were recovered from an inpatient who had been hospitalized for 20 days. Three of the isolates exhibited a non-HMV phenotype, which was concomitant with higher biofilm formation than the other five HMV isolates. All eight isolates were highly susceptible to serum killing, albeit HMV strains were remarkably more infective than non-HMV counterparts in a mouse model of infection. Whole genome sequencing (WGS) showed that the eight isolates belonged to the K57-ST412 lineage. Average nucleotide identity (FastANIb) analysis indicated that eight isolates share 99.96% to 99.99% similarity and were confirmed to be the same clone. Through comparative genomics analysis, 12 non-synonymous mutations were found among these isolates, eight of which in the non-HMV variants, including rmpA (c.285delG) and wbaP (c.1305T > A), which are assumed to be associated with the non-HMV phenotype. Mutations in manB (c.1318G > A), dmsB (c.577C > T) and tkt (c.1928C > A) occurred in HMV isolates only. RNA-Seq revealed transcripts of genes involved in energy metabolism, carbohydrate metabolism and membrane transport, including cysP, cydA, narK, tktA, pduQ, aceB, metN, and lsrA, to be significantly dysregulated in the non-HMV strains, suggesting a contribution to HMV phenotype development. This study suggests that co-occurrence of HMV and non-HMV phenotypes in the same clonal population may be mediated by mutational mechanisms as well as by certain genes involved in membrane transport and central metabolism. IMPORTANCE K. pneumoniae with a hypermucoviscosity (HMV) phenotype is a community-acquired pathogen that is associated with increased invasiveness and pathogenicity, and underlying diseases are the most common comorbid risk factors inducing metastatic complications. HMV was earlier attributed to the overproduction of capsular polysaccharide, and more data point to the possibility of several causes contributing to this bacterial phenotype. Here, we describe a unique event in which the same clonal population showed both HMV and non-HMV characteristics. Studies have demonstrated that this process is influenced by mutational processes and genes related to transport and central metabolism. These findings provide fresh insight into the mechanisms behind co-occurrence of HMV and non-HMV phenotypes in monoclonal populations as well as potentially being critical in developing strategies to control the further spread of HMV K. pneumoniae.
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Affiliation(s)
- Qinghua Liang
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
- Department of Laboratory Medicine, Yilong County People's Hospital, Nanchong, China
| | - Nan Chen
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Wei Wang
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Biying Zhang
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Jinjing Luo
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Ying Zhong
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Feiyang Zhang
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Zhikun Zhang
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Alberto J Martín-Rodríguez
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Sciences, University of Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain
| | - Ying Wang
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Li Xiang
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
| | - Xia Xiong
- Department of Dermatology, The Affiliated Hospital,Southwest Medical University, Luzhou, China
| | - Renjing Hu
- Department of Laboratory Medicine, Jiangnan University Medical Center, Wuxi, China
| | - Yingshun Zhou
- Department of Pathogenic Biology, School of Basic Medical, Southwest Medical University, Luzhou, China
- Public Center of Experimental Technology of Pathogen Biology Technology Platform, Southwest Medicine University, Luzhou, China
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Teng G, Zhang M, Fu Y, Yang X, Kang Y, Qin Q, Jin Y, Huang M, Xu Y. Adaptive attenuation of virulence in hypervirulent carbapenem-resistant Klebsiella pneumoniae. mSystems 2024; 9:e0136323. [PMID: 38752758 DOI: 10.1128/msystems.01363-23] [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: 12/16/2023] [Accepted: 04/17/2024] [Indexed: 06/19/2024] Open
Abstract
The emergence of nosocomial infections caused by hypervirulent and carbapenem-resistant K. pneumoniae (hv-CRKP) has become a significant public health challenge. The genetic traits of virulence and resistance plasmids in hv-CRKP have been extensively studied; however, research on the adaptive evolution strategies of clinical strains inside the host was scarce. This study aimed to understand the effects of antibiotic treatment on the phenotype and genotype characteristics of hv-CRKP. We investigated the evolution of hv-CRKP strains isolated from the same patient to elucidate the transition between hospital invasion and colonization. A comparative genomics analysis was performed to identify single nucleotide polymorphisms in the rmpA promoter. Subsequent validation through RNA-seq and gene deletion confirmed that distinct rmpA promoter sequences exert control over the mucoid phenotype. Additionally, biofilm experiments, cell adhesion assays, and animal infection models were conducted to illuminate the influence of rmpA promoter diversity on virulence changes. We demonstrated that the P12T and P11T promoters of rmpA possess strong activity, which leads to the evolution of CRKP into infectious and virulent strains. Meanwhile, the specific sequence of polyT motifs in the rmpA promoter led to a decrease in the lethality of hv-CRKP and enhanced cell adhesion and colonization. To summarize, the rmpA promoter of hv-CRKP is utilized to control capsule production, thereby modifying pathogenicity to better suit the host's ecological environment.IMPORTANCEThe prevalence of hospital-acquired illness caused by hypervirulent carbapenem-resistant Klebsiella pneumoniae (hv-CRKP) is significant, leading to prolonged antibiotic treatment. However, there are few reports on the phenotypic changes of hv-CRKP in patients undergoing antibiotic treatment. We performed a comprehensive examination of the genetic evolutionary traits of hv-CRKP obtained from the same patient and observed variations in the promoter sequences of the virulence factor rmpA. The strong activity of the promoter sequences P11T and P12T enhances the consistent production of capsule polysaccharides, resulting in an invasive strain. Conversely, weak promoter activity of P9T and P10T is advantageous for exposing pili, hence improving bacterial cell attachment ability and facilitating bacterial colonization. This finding also explains the confusion of some clinical strains carrying wild-type rmpA but exhibiting a low mucoid phenotype. This adaptive alteration facilitates the dissemination of K. pneumoniae within the hospital setting.
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Affiliation(s)
- Gaoqin Teng
- Department of Immunology and Pathogen Biology, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
- Key Laboratory of Multiple Organ Failure, Ministry of Education, Hangzhou, China
- Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Meng Zhang
- Department of Immunology and Pathogen Biology, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| | - YingYing Fu
- Department of Immunology and Pathogen Biology, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| | - Xiaoqiang Yang
- Department of Immunology and Pathogen Biology, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| | - Yanhua Kang
- Department of Immunology and Pathogen Biology, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| | - Qiuying Qin
- Department of Immunology and Pathogen Biology, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| | - Ye Jin
- Key Laboratory of Multiple Organ Failure, Ministry of Education, Hangzhou, China
- Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Man Huang
- Key Laboratory of Multiple Organ Failure, Ministry of Education, Hangzhou, China
- Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yongchang Xu
- Department of Immunology and Pathogen Biology, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
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3
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Goh KJ, Altuvia Y, Argaman L, Raz Y, Bar A, Lithgow T, Margalit H, Gan YH. RIL-seq reveals extensive involvement of small RNAs in virulence and capsule regulation in hypervirulent Klebsiella pneumoniae. Nucleic Acids Res 2024:gkae440. [PMID: 38804271 DOI: 10.1093/nar/gkae440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 04/29/2024] [Accepted: 05/09/2024] [Indexed: 05/29/2024] Open
Abstract
Hypervirulent Klebsiella pneumoniae (hvKp) can infect healthy individuals, in contrast to classical strains that commonly cause nosocomial infections. The recent convergence of hypervirulence with carbapenem-resistance in K. pneumoniae can potentially create 'superbugs' that are challenging to treat. Understanding virulence regulation of hvKp is thus critical. Accumulating evidence suggest that posttranscriptional regulation by small RNAs (sRNAs) plays a role in bacterial virulence, but it has hardly been studied in K. pneumoniae. We applied RIL-seq to a prototypical clinical isolate of hvKp to unravel the Hfq-dependent RNA-RNA interaction (RRI) network. The RRI network is dominated by sRNAs, including predicted novel sRNAs, three of which we validated experimentally. We constructed a stringent subnetwork composed of RRIs that involve at least one hvKp virulence-associated gene and identified the capsule gene loci as a hub target where multiple sRNAs interact. We found that the sRNA OmrB suppressed both capsule production and hypermucoviscosity when overexpressed. Furthermore, OmrB base-pairs within kvrA coding region and partially suppresses translation of the capsule regulator KvrA. This agrees with current understanding of capsule as a major virulence and fitness factor. It emphasizes the intricate regulatory control of bacterial phenotypes by sRNAs, particularly of genes critical to bacterial physiology and virulence.
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Affiliation(s)
- Kwok Jian Goh
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117596, Singapore
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Yael Altuvia
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Liron Argaman
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Yair Raz
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Amir Bar
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Trevor Lithgow
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Hanah Margalit
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Yunn-Hwen Gan
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117596, Singapore
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4
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Nonne F, Molfetta M, Nappini R, La Guidara C, Di Benedetto R, Mfana S, Bellich B, Raso MM, Gasperini G, Alfini R, Cescutti P, Berlanda Scorza F, Ravenscroft N, Micoli F, Giannelli C. Development and Application of a High-Throughput Method for the Purification and Analysis of Surface Carbohydrates from Klebsiella pneumoniae. BIOLOGY 2024; 13:256. [PMID: 38666868 PMCID: PMC11048683 DOI: 10.3390/biology13040256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/08/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024]
Abstract
Klebsiella pneumoniae (Kp) is a Gram-negative bacterium, and a leading cause of neonatal sepsis in low- and middle-income countries, often associated with anti-microbial resistance. Two types of polysaccharides are expressed on the Kp cell surface and have been proposed as key antigens for vaccine design: capsular polysaccharides (known as K-antigens, K-Ags) and O-antigens (O-Ags). Historically, Kp has been classified using capsule serotyping and although 186 distinct genotypes have been predicted so far based on sequence analysis, many structures are still unknown. In contrast, only 11 distinct OAg serotypes have been described. The characterization of emerging strains requires the development of a high-throughput purification method to obtain sufficient K- and O-Ag material to characterize the large collection of serotypes and gain insight on structural features and potential cross-reactivity that could allow vaccine simplification. Here, this was achieved by adapting our established method for the simple purification of O-Ags, using mild acetic acid hydrolysis performed directly on bacterial cells, followed by filtration and precipitation steps. The method was successfully applied to purify the surface carbohydrates from different Kp strains, thereby demonstrating the robustness and general applicability of the purification method developed. Further, antigen characterization showed that the purification method had no impact on the structural integrity of the polysaccharides and preserved labile substituents such as O-acetyl and pyruvyl groups. This method can be further optimized for scaling up and manufacturing to support the development of high-valency saccharide-based vaccines against Kp.
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Affiliation(s)
- Francesca Nonne
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
| | - Mariagrazia Molfetta
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
| | - Rebecca Nappini
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
- Department of Life Science, University of Trieste, 34127 Trieste, Italy;
| | - Chiara La Guidara
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
| | - Roberta Di Benedetto
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
| | - Siwaphiwe Mfana
- Department of Chemistry, University of Cape Town, Cape Town 7700, South Africa; (S.M.); (N.R.)
| | - Barbara Bellich
- Department of Advanced Translational Diagnostics, Institute for Maternal and Child Health, IRCCS “Burlo Garofolo”, 34137 Trieste, Italy;
| | - Maria Michelina Raso
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
| | | | - Renzo Alfini
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
| | - Paola Cescutti
- Department of Life Science, University of Trieste, 34127 Trieste, Italy;
| | - Francesco Berlanda Scorza
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
| | - Neil Ravenscroft
- Department of Chemistry, University of Cape Town, Cape Town 7700, South Africa; (S.M.); (N.R.)
| | - Francesca Micoli
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
| | - Carlo Giannelli
- GSK Vaccines Institute for Global Health, 53100 Siena, Italy; (M.M.); (R.N.); (C.L.G.); (R.D.B.); (M.M.R.); (R.A.); (F.B.S.); (F.M.); (C.G.)
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5
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Rojas D, Marcoleta AE, Gálvez-Silva M, Varas MA, Díaz M, Hernández M, Vargas C, Nourdin-Galindo G, Koch E, Saldivia P, Vielma J, Gan YH, Chen Y, Guiliani N, Chávez FP. Inorganic Polyphosphate Affects Biofilm Assembly, Capsule Formation, and Virulence of Hypervirulent ST23 Klebsiella pneumoniae. ACS Infect Dis 2024; 10:606-623. [PMID: 38205780 DOI: 10.1021/acsinfecdis.3c00509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
The emergence of hypervirulent Klebsiella pneumoniae (hvKP) strains poses a significant threat to public health due to high mortality rates and propensity to cause severe community-acquired infections in healthy individuals. The ability to form biofilms and produce a protective capsule contributes to its enhanced virulence and is a significant challenge to effective antibiotic treatment. Polyphosphate kinase 1 (PPK1) is an enzyme responsible for inorganic polyphosphate synthesis and plays a vital role in regulating various physiological processes in bacteria. In this study, we investigated the impact of polyP metabolism on the biofilm and capsule formation and virulence traits in hvKP using Dictyostelium discoideum amoeba as a model host. We found that the PPK1 null mutant was impaired in biofilm and capsule formation and showed attenuated virulence in D. discoideum compared to the wild-type strain. We performed a proteomic analysis to gain further insights into the underlying molecular mechanism. The results revealed that the PPK1 mutant had a differential expression of proteins involved in capsule synthesis (Wzi-Ugd), biofilm formation (MrkC-D-H), synthesis of the colibactin genotoxin precursor (ClbB), as well as proteins associated with the synthesis and modification of lipid A (ArnB-LpxC-PagP). These proteomic findings corroborate the phenotypic observations and indicate that the PPK1 mutation is associated with impaired biofilm and capsule formation and attenuated virulence in hvKP. Overall, our study highlights the importance of polyP synthesis in regulating extracellular biomolecules and virulence in K. pneumoniae and provides insights into potential therapeutic targets for treating K. pneumoniae infections.
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Affiliation(s)
- Diego Rojas
- Laboratorio de Microbiología de Sistemas, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
| | - Andrés E Marcoleta
- Grupo de Microbiología Integrativa, Laboratorio de Biología Estructural y Molecular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
| | - Matías Gálvez-Silva
- Laboratorio de Microbiología de Sistemas, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
- Grupo de Microbiología Integrativa, Laboratorio de Biología Estructural y Molecular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
| | - Macarena A Varas
- Laboratorio de Microbiología de Sistemas, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
- Grupo de Microbiología Integrativa, Laboratorio de Biología Estructural y Molecular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
| | - Mauricio Díaz
- Laboratorio de Comunicación Microbiana, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
| | - Mauricio Hernández
- División Biotecnología, Instituto Melisa, San Pedro de la Paz CP 9660000, Chile
| | - Cristian Vargas
- División Biotecnología, Instituto Melisa, San Pedro de la Paz CP 9660000, Chile
| | | | - Elard Koch
- División Biotecnología, Instituto Melisa, San Pedro de la Paz CP 9660000, Chile
| | - Pablo Saldivia
- División Biotecnología, Instituto Melisa, San Pedro de la Paz CP 9660000, Chile
- Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción CP 4070389, Chile
| | - Jorge Vielma
- Laboratorio de Microbiología de Sistemas, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
- Grupo de Microbiología Integrativa, Laboratorio de Biología Estructural y Molecular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
| | - Yunn-Hwen Gan
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore CP 119077, Singapore
| | - Yahua Chen
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore CP 119077, Singapore
| | - Nicolás Guiliani
- Laboratorio de Comunicación Microbiana, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
| | - Francisco P Chávez
- Laboratorio de Microbiología de Sistemas, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago CP 7800003, Chile
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6
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Pu D, Zhao J, Chang K, Zhuo X, Cao B. "Superbugs" with hypervirulence and carbapenem resistance in Klebsiella pneumoniae: the rise of such emerging nosocomial pathogens in China. Sci Bull (Beijing) 2023; 68:2658-2670. [PMID: 37821268 DOI: 10.1016/j.scib.2023.09.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 08/19/2023] [Accepted: 09/26/2023] [Indexed: 10/13/2023]
Abstract
Although hypervirulent Klebsiella pneumoniae (hvKP) can produce community-acquired infections that are fatal in young and adult hosts, such as pyogenic liver abscess, endophthalmitis, and meningitis, it has historically been susceptible to antibiotics. Carbapenem-resistant K. pneumoniae (CRKP) is usually associated with urinary tract infections acquired in hospitals, pneumonia, septicemias, and soft tissue infections. Outbreaks and quick spread of CRKP in hospitals have become a major challenge in public health due to the lack of effective antibacterial treatments. In the early stages of K. pneumoniae development, HvKP and CRKP first appear as distinct routes. However, the lines dividing the two pathotypes are vanishing currently, and the advent of carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP) is devastating as it is simultaneously multidrug-resistant, hypervirulent, and highly transmissible. Most CR-hvKP cases have been reported in Asian clinical settings, particularly in China. Typically, CR-hvKP develops when hvKP or CRKP acquires plasmids that carry either the carbapenem-resistance gene or the virulence gene. Alternatively, classic K. pneumoniae (cKP) may acquire a hybrid plasmid carrying both genes. In this review, we provide an overview of the key antimicrobial resistance mechanisms, virulence factors, clinical presentations, and outcomes associated with CR-hvKP infection. Additionally, we discuss the possible evolutionary processes and prevalence of CR-hvKP in China. Given the wide occurrence of CR-hvKP, continued surveillance and control measures of such organisms should be assigned a higher priority.
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Affiliation(s)
- Danni Pu
- Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100730, China; Laboratory of Clinical Microbiology and Infectious Diseases, Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, National Center for Respiratory Medicine, China-Japan Friendship Hospital, Beijing 100029, China; Institute of Respiratory Medicine, Chinese Academy of Medical Sciences, Beijing 100029, China
| | - Jiankang Zhao
- Laboratory of Clinical Microbiology and Infectious Diseases, Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, National Center for Respiratory Medicine, China-Japan Friendship Hospital, Beijing 100029, China; Institute of Respiratory Medicine, Chinese Academy of Medical Sciences, Beijing 100029, China
| | - Kang Chang
- Laboratory of Clinical Microbiology and Infectious Diseases, Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, National Center for Respiratory Medicine, China-Japan Friendship Hospital, Beijing 100029, China; Institute of Respiratory Medicine, Chinese Academy of Medical Sciences, Beijing 100029, China
| | - Xianxia Zhuo
- Laboratory of Clinical Microbiology and Infectious Diseases, Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, National Center for Respiratory Medicine, China-Japan Friendship Hospital, Beijing 100029, China; Institute of Respiratory Medicine, Chinese Academy of Medical Sciences, Beijing 100029, China; Department of Pulmonary and Critical Care Medicine, Capital Medical University, Beijing 100069, China
| | - Bin Cao
- Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100730, China; Laboratory of Clinical Microbiology and Infectious Diseases, Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, National Center for Respiratory Medicine, China-Japan Friendship Hospital, Beijing 100029, China; Institute of Respiratory Medicine, Chinese Academy of Medical Sciences, Beijing 100029, China; Department of Pulmonary and Critical Care Medicine, Capital Medical University, Beijing 100069, China; Tsinghua University-Peking University Joint Center for Life Sciences, Beijing 100084, China.
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7
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Khadka S, Ring BE, Walker RS, Krzeminski LR, Pariseau DA, Hathaway M, Mobley HLT, Mike LA. Urine-mediated suppression of Klebsiella pneumoniae mucoidy is counteracted by spontaneous Wzc variants altering capsule chain length. mSphere 2023; 8:e0028823. [PMID: 37610214 PMCID: PMC10597399 DOI: 10.1128/msphere.00288-23] [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: 05/31/2023] [Accepted: 06/14/2023] [Indexed: 08/24/2023] Open
Abstract
Klebsiella pneumoniae is a hospital-associated pathogen primarily causing urinary tract infections (UTIs), pneumonia, and septicemia. Two challenging lineages include the hypervirulent strains, causing invasive community-acquired infections, and the carbapenem-resistant classical strains, most frequently isolated from UTIs. While hypervirulent strains are often characterized by a hypermucoid phenotype, classical strains usually present with low mucoidy. Since clinical UTI isolates tend to exhibit limited mucoidy, we hypothesized that environmental conditions may drive K. pneumoniae adaptation to the urinary tract and select against mucoid isolates. We found that both hypervirulent K. pneumoniae and classical Klebsiella UTI isolates significantly suppressed mucoidy when cultured in urine without reducing capsule abundance. A genetic screen identified secondary mutations in the wzc tyrosine kinase that overcome urine-suppressed mucoidy. Over-expressing Wzc variants in trans was sufficient to boost mucoidy in both hypervirulent and classical Klebsiella UTI isolates. Wzc is a bacterial tyrosine kinase that regulates capsule polymerization and extrusion. Although some Wzc variants reduced Wzc phospho-status, urine did not alter Wzc phospho-status. Urine does, however, increase K. pneumoniae capsule chain length diversity and enhance cell-surface attachment. The identified Wzc variants counteract urine-mediated effects on capsule chain length and cell attachment. Combined, these data indicate that capsule chain length correlates with K. pneumoniae mucoidy and that this extracellular feature can be fine-tuned by spontaneous Wzc mutations, which alter host interactions. Spontaneous Wzc mutation represents a global mechanism that could fine-tune K. pneumoniae niche-specific fitness in both classical and hypervirulent isolates. IMPORTANCE Klebsiella pneumoniae is high-priority pathogen causing both hospital-associated infections, such as urinary tract infections, and community-acquired infections. Clinical isolates from community-acquired infection are often characterized by a tacky, hypermucoid phenotype, while urinary tract isolates are usually not mucoid. Historically, mucoidy was attributed to capsule overproduction; however, recent reports have demonstrated that K. pneumoniae capsule abundance and mucoidy are not always correlated. Here, we report that human urine suppresses K. pneumoniae mucoidy, diversifies capsule polysaccharide chain length, and increases cell surface association. Moreover, specific mutations in the capsule biosynthesis gene, wzc, are sufficient to overcome urine-mediated suppression of mucoidy. These Wzc variants cause constitutive production of more uniform capsular polysaccharide chains and increased release of capsule from the cell surface, even in urine. These data demonstrate that K. pneumoniae regulates capsule chain length and cell surface attachment in response host cues, which can alter bacteria-host interactions.
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Affiliation(s)
- Saroj Khadka
- Medical Microbiology and Immunology, University of Toledo , Toledo, Ohio, USA
| | - Brooke E Ring
- Medical Microbiology and Immunology, University of Toledo , Toledo, Ohio, USA
| | - Ryan S Walker
- Microbiology and Immunology, University of Michigan , Ann Arbor, Michigan, USA
| | | | - Drew A Pariseau
- Medical Microbiology and Immunology, University of Toledo , Toledo, Ohio, USA
| | - Matthew Hathaway
- Medical Microbiology and Immunology, University of Toledo , Toledo, Ohio, USA
| | - Harry L T Mobley
- Microbiology and Immunology, University of Michigan , Ann Arbor, Michigan, USA
| | - Laura A Mike
- Medical Microbiology and Immunology, University of Toledo , Toledo, Ohio, USA
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8
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Wantuch PL, Rosen DA. Klebsiella pneumoniae: adaptive immune landscapes and vaccine horizons. Trends Immunol 2023; 44:826-844. [PMID: 37704549 DOI: 10.1016/j.it.2023.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 09/15/2023]
Abstract
Klebsiella pneumoniae is among the most common antibiotic-resistant pathogens causing nosocomial infections. Additionally, it is a leading cause of neonatal sepsis and childhood mortality across the globe. Despite its clinical importance, we are only beginning to understand how the mammalian adaptive immune system responds to this pathogen. Further, many studies investigating potential K. pneumoniae vaccine candidates or alternative therapies have been launched in recent years. Here, we review the current state of knowledge on the adaptive immune response to K. pneumoniae infections and progress towards developing vaccines and other therapies to combat these infections.
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Affiliation(s)
- Paeton L Wantuch
- Department of Pediatrics, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - David A Rosen
- Department of Pediatrics, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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9
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Nucci A, Janaszkiewicz J, Rocha EPC, Rendueles O. Emergence of novel non-aggregative variants under negative frequency-dependent selection in Klebsiella variicola. MICROLIFE 2023; 4:uqad038. [PMID: 37781688 PMCID: PMC10540941 DOI: 10.1093/femsml/uqad038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/05/2023] [Accepted: 09/09/2023] [Indexed: 10/03/2023]
Abstract
Klebsiella variicola is an emergent human pathogen causing diverse infections, some of which in the urinary tract. However, little is known about the evolution and maintenance of genetic diversity in this species, the molecular mechanisms and their population dynamics. Here, we characterized the emergence of a novel rdar-like (rough and dry) morphotype which is contingent both on the genetic background and the environment. We show that mutations in either the nitrogen assimilation control gene (nac) or the type III fimbriae regulator, mrkH, suffice to generate rdar-like colonies. These morphotypes are primarily selected for the reduced inter-cellular aggregation as a result of MrkH loss-of-function which reduces type 3 fimbriae expression. Additionally, these clones also display increased growth rate and reduced biofilm formation. Direct competitions between rdar and wild type clones show that mutations in mrkH provide large fitness advantages. In artificial urine, the morphotype is under strong negative frequency-dependent selection and can socially exploit wild type strains. An exhaustive search for mrkH mutants in public databases revealed that ca 8% of natural isolates analysed had a truncated mrkH gene many of which were due to insertions of IS elements, including a reported clinical isolate with rdar morphology. These strains were rarely hypermucoid and often isolated from human, mostly from urine and blood. The decreased aggregation of these mutants could have important clinical implications as we hypothesize that such clones could better disperse within the host allowing colonisation of other body sites and potentially leading to systemic infections.
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Affiliation(s)
- Amandine Nucci
- Institut Pasteur, Université Paris Cité, CNRS, UMR3525, Microbial Evolutionary Genomics, F-75015, Paris, France
| | - Juliette Janaszkiewicz
- Institut Pasteur, Université Paris Cité, CNRS, UMR3525, Microbial Evolutionary Genomics, F-75015, Paris, France
| | - Eduardo P C Rocha
- Institut Pasteur, Université Paris Cité, CNRS, UMR3525, Microbial Evolutionary Genomics, F-75015, Paris, France
| | - Olaya Rendueles
- Institut Pasteur, Université Paris Cité, CNRS, UMR3525, Microbial Evolutionary Genomics, F-75015, Paris, France
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10
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Chen J, Zhang H, Liao X. Hypervirulent Klebsiella pneumoniae. Infect Drug Resist 2023; 16:5243-5249. [PMID: 37589017 PMCID: PMC10426436 DOI: 10.2147/idr.s418523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 08/03/2023] [Indexed: 08/18/2023] Open
Abstract
Hypervirulent Klebsiella pneumoniae (hvKP), especially multidrug-resistant hvKP (MDR-hvKP) infections, are distributed globally, and lead to several outbreaks with high pathogenicity and mortality in immunocompetent individuals. This is usually characterized by a rapidly metastatic spread resulting in multiple pyogenic tissue abscesses. To date, even though the explanation of hypervirulent factors of hvKP has been identified, it still remains to be fully understood. The most common key virulence agents of hvKP included (1) siderophore systems for iron acquisition, (2) increased capsule production, (3) the colibactin toxin, (4) hypermucoviscosity, and so on. Several hypervirulence factors have been renewed, and the evolution of MDR-hvKP has been deeply explored recently. We aim to describe a chain of key virulence agents attributed to the lethality of hvKP and MDR-hvKP. In this review, recent advances in renewed factors in hypervirulence were summarized, and potential therapeutic targets are explored. Novel co-existence of hypervirulence agents and multidrug-resistant elements, even the superplasmid, was screened. Superplasmid simultaneously harbours hypervirulence and multidrug-resistant genes and can mobile autonomously by its complete conjugative elements. Research into related immunity has also gained traction, which may cause multiple invasive infections with higher mortality rates than classical ones, such as neutrophil- and complement-mediated activity. The evolution of virulence and multidrug resistance is accelerating. More reliable methods for identifying hvKP or MDR-hvKP must be investigated. Furthermore, it is critical to investigate innovative treatment targets in the future.
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Affiliation(s)
- Junjun Chen
- Department of Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
- Department of Critical Care Medicine, West China Tianfu Hospital of Sichuan University, Chengdu, People’s Republic of China
| | - Huan Zhang
- Department of Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
- Department of Cardiac Vascular Surgery Critical Care Medicine, The Third People’s Hospital of Chengdu, Chengdu, People’s Republic of China
| | - Xuelian Liao
- Department of Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, People’s Republic of China
- Department of Critical Care Medicine, West China Tianfu Hospital of Sichuan University, Chengdu, People’s Republic of China
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