Virulence profiles of Klebsiella pneumoniae isolated from 2 large dairy farms in China.

We recently reported on the diversity of Klebsiella pneumoniae isolated from dairy herds in China. In our previous work, isolates from subclinical mastitis (SCM) had lower indices of diversity when compared with bacteria from other sources, possibly due to a contagious-like spread of udder adapted strains. Here we explored the virulence profile and capsular types of K. pneumoniae isolated from different sources on 2 dairy farms in China. Our overarching goal was to gain insights on the role of virulence genes toward the severity of mastitis caused by K. pneumoniae. A total of 1,484 samples were collected from clinical mastitis (CM; n = 355), SCM (n = 561), bulk tank milk (BTM; n = 130), and environmental and extramammary (EE) sites (n = 438). From those, 431 K. pneumoniae isolates were obtained, including 129, 77, 66, and 159 isolates from CM, SCM, BTM, and EE samples, respectively. Polymerase chain reactions were used to determine the capsular types and to detect potential virulence genes in all isolates. No significant farm effects were observed when comparing the distribution of most virulence genes in K. pneumoniae isolated from each source. K57 was the most prevalent capsular type in K. pneumoniae from all sources, but with increased detection rate in isolates from CM. entB, kfu, fimH1, mrkD, and β-d-lacZ were frequently detected in K. pneumoniae from all sources. β-d-lacZ, entB, and ituA were more prevalent in isolates from CM, whereas kfu, allS, and nif were more frequently detected in isolates from SCM. ybtS, aerobactin, and rpmA had increased prevalence in K. pneumoniae from BTM when compared with bacteria from other sources. No association was detected between virulence genes and the severity of CM. K57 and the nif gene had the highest discriminatory power to classify isolates from CM and SCM, respectively. Based on our findings, it is likely that K57 is the dominant capsular type in K. pneumoniae causing CM in large Chinese dairy herds. Likewise, we demonstrated that β-d-lacZ is disseminated in K. pneumoniae isolated from large Chinese dairy farms, irrespectively of the source of bacteria. Our results also suggest a low contribution of the virulence profile of K. pneumoniae toward CM severity. Finally, the role of nif in increasing the adaptability to the udder and promoting a contagious-like spread of K. pneumoniae warrants further investigation.

[1]  H. Barkema,et al.  Genetic diversity and molecular epidemiology of outbreaks of Klebsiella pneumoniae mastitis on two large Chinese dairy farms. , 2020, Journal of dairy science.

[2]  Yang Liu,et al.  Microbiological and Clinical Characteristics of Klebsiella pneumoniae Isolates of K57 Capsular Serotype in China. , 2020, Microbial drug resistance.

[3]  H. Barkema,et al.  Klebsiella pneumoniae isolated from bovine mastitis is cytopathogenic for bovine mammary epithelial cells. , 2020, Journal of dairy science.

[4]  X. Zhong,et al.  Comparisons of microbiological characteristics and antibiotic resistance of Klebsiella pneumoniae isolates from urban rodents, shrews, and healthy people , 2020, BMC Microbiology.

[5]  H. Barkema,et al.  Prevalence of Potential Virulence Genes in Klebsiella spp. Isolated from Cows with Clinical Mastitis on Large Chinese Dairy Farms. , 2019, Foodborne pathogens and disease.

[6]  R. Zadoks,et al.  An update on environmental mastitis: Challenging perceptions , 2018, Transboundary and emerging diseases.

[7]  Qingping Wu,et al.  Phenotypic and Genotypic Characterization of Klebsiella pneumoniae Isolated From Retail Foods in China , 2018, Front. Microbiol..

[8]  Luhua Zhang,et al.  Frequency of virulence factors in high biofilm formation blaKPC-2 producing Klebsiella pneumoniae strains from hospitals. , 2018, Microbial pathogenesis.

[9]  K. Ko.  The contribution of capsule polysaccharide genes to virulence of Klebsiella pneumoniae , 2017, Virulence.

[10]  H. Barkema,et al.  Incidence of clinical mastitis and distribution of pathogens on large Chinese dairy farms. , 2017, Journal of dairy science.

[11]  Liangxing Wang,et al.  Microbiological and Clinical Characteristics of Hypermucoviscous Klebsiella pneumoniae Isolates Associated with Invasive Infections in China , 2017, Front. Cell. Infect. Microbiol..

[12]  W. Elkhatib,et al.  Molecular typing and virulence analysis of multidrug resistant Klebsiella pneumoniae clinical isolates recovered from Egyptian hospitals , 2016, Scientific Reports.

[13]  Shih-Hsiung Wu,et al.  Identification of a capsular variant and characterization of capsular acetylation in Klebsiella pneumoniae PLA-associated type K57 , 2016, Scientific Reports.

[14]  J. Mecsas,et al.  Klebsiella pneumoniae: Going on the Offense with a Strong Defense , 2016, Microbiology and Molecular Reviews.

[15]  T. Knöbl,et al.  Virulence and antimicrobial resistance of Klebsiella pneumoniae isolated from passerine and psittacine birds , 2016, Avian pathology : journal of the W.V.P.A.

[16]  Jonathan Wilksch,et al.  Genomic analysis of diversity, population structure, virulence, and antimicrobial resistance in Klebsiella pneumoniae, an urgent threat to public health , 2015, Proceedings of the National Academy of Sciences.

[17]  S. Brisse,et al.  Multiplex PCR for Detection of Seven Virulence Factors and K1/K2 Capsular Serotypes of Klebsiella pneumoniae , 2014, Journal of Clinical Microbiology.

[18]  Shengli Li,et al.  Prevalence of Bovine Mastitis Pathogens in Bulk Tank Milk in China , 2014, PloS one.

[19]  H. Hassan,et al.  Phenotypic, antimicrobial susceptibility profile and virulence factors of Klebsiella pneumoniae isolated from buffalo and cow mastitic milk , 2014, Pathogens and global health.

[20]  T. Russo,et al.  Aerobactin Mediates Virulence and Accounts for Increased Siderophore Production under Iron-Limiting Conditions by Hypervirulent (Hypermucoviscous) Klebsiella pneumoniae , 2014, Infection and Immunity.

[21]  P. Ruegg,et al.  Characterization of clinical mastitis occurring in cows on 50 large dairy herds in Wisconsin. , 2013, Journal of dairy science.

[22]  T. Russo,et al.  Hypervirulent (hypermucoviscous) Klebsiella pneumoniae , 2013, Virulence.

[23]  R. Zadoks,et al.  The "other" gram-negative bacteria in mastitis: Klebsiella, serratia, and more. , 2012, The Veterinary clinics of North America. Food animal practice.

[24]  F. Gulland,et al.  Pleuritis and suppurative pneumonia associated with a hypermucoviscosity phenotype of Klebsiella pneumoniae in California sea lions (Zalophus californianus). , 2010, Veterinary microbiology.

[25]  M. Munoz,et al.  Cleanliness scores as indicator of Klebsiella exposure in dairy cows. , 2008, Journal of dairy science.

[26]  Jia Yu,et al.  PCR detection of Klebsiella pneumoniae in infant formula based on 16S-23S internal transcribed spacer. , 2008, International journal of food microbiology.

[27]  M. Kaufmann,et al.  Evaluation of a multiplex PCR for detection of serotypes K1, K2 and K5 in Klebsiella sp. and comparison of isolates within these serotypes. , 2008, FEMS microbiology letters.

[28]  C. Struve,et al.  Characterization of Klebsiella pneumoniae Type 1 Fimbriae by Detection of Phase Variation during Colonization and Infection and Impact on Virulence , 2008, Infection and Immunity.

[29]  Y. Keynan,et al.  Capsular Polysaccharide Synthesis Regions in Klebsiella pneumoniae Serotype K57 and a New Capsular Serotype , 2008, Journal of Clinical Microbiology.

[30]  D. Kelton,et al.  Incidence rate of clinical mastitis on Canadian dairy farms. , 2008, Journal of dairy science.

[31]  G. Olsen,et al.  Critical Evaluation of Two Primers Commonly Used for Amplification of Bacterial 16S rRNA Genes , 2008, Applied and Environmental Microbiology.

[32]  M. Munoz,et al.  Molecular Epidemiology of Two Klebsiella pneumoniae Mastitis Outbreaks on a Dairy Farm in New York State , 2007, Journal of Clinical Microbiology.

[33]  P. Hsueh,et al.  Klebsiella pneumoniae genotype K1: an emerging pathogen that causes septic ocular or central nervous system complications from pyogenic liver abscess. , 2007, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[34]  H. Goossens,et al.  Virulence Characteristics of Klebsiella and Clinical Manifestations of K. pneumoniae Bloodstream Infections , 2007, Emerging infectious diseases.

[35]  W. Ko,et al.  Polymerase chain reaction analysis for detecting capsule serotypes K1 and K2 of Klebsiella pneumoniae causing abscesses of the liver and other sites. , 2007, The Journal of infectious diseases.

[36]  M. Munoz,et al.  Fecal shedding of Klebsiella pneumoniae by dairy cows. , 2006, Journal of dairy science.

[37]  Y. Schukken,et al.  Effect of pathogen-specific clinical mastitis on milk yield in dairy cows. , 2004, Journal of dairy science.

[38]  Chia-Tung Shun,et al.  A Novel Virulence Gene in Klebsiella pneumoniae Strains Causing Primary Liver Abscess and Septic Metastatic Complications , 2004, The Journal of experimental medicine.

[39]  S. Clegg,et al.  Klebsiella pneumoniae MrkD-mediated biofilm formation on extracellular matrix- and collagen-coated surfaces. , 2003, Microbiology.

[40]  L. Duchateau,et al.  Severity of E. coli mastitis is mainly determined by cow factors. , 2003, Veterinary research.

[41]  A. D. de Almeida,et al.  The Yersinia high-pathogenicity island is present in different members of the family Enterobacteriaceae. , 2000, FEMS microbiology letters.

[42]  Timo K. Korhonen,et al.  Immunohistological Localization of the MrkD Adhesin in the Type 3 Fimbriae of Klebsiella pneumoniae , 1998, Infection and Immunity.

[43]  N. Kikuchi,et al.  Plasmid profiles of Klebsiella pneumoniae isolated from bovine mastitis. , 1995, Veterinary microbiology.

[44]  Geoffrey E. Hinton,et al.  Visualizing Data using t-SNE , 2008 .

[45]  Y. Benjamini,et al.  Controlling the false discovery rate: a practical and powerful approach to multiple testing , 1995 .