Genetic Determinants of Capsular Serotype K1 of<i>Klebsiella pneumoniae</i>Causing Primary Pyogenic Liver Abscess

Chuang, Yung-Yu; Fang, Chi-Tai; Lai, Shau-Yan; Chang, Shan-Chwen; Wang, Jann-Tay

doi:10.1086/499968

Cited by 199 publications

(225 citation statements)

References 36 publications

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“…Furthermore, molecular serotyping is capable to determine a potential serotype of capsule-deficient isolates (7,18,19). We recommend that PCR analysis could be helpful in seroepidemiologic studies and early-tracing of contingent metastatic infections in patients with liver abscess (7,10,11,(15)(16)(17)(18)(19)(20). This is the first report on the occurrence of serotypes K1 and K2 in the clinical specimens and shows the pathogenic potential of these isolates in different organs.…”

Section: Discussionmentioning

confidence: 89%

Identification of Klebsiella pneumoniae K1 and K2 Capsular Types by PCR and Quellung Test

Feizabadi

Raji

Delfani

2013

Jundishapur J Microbiol

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Background: Klebseilla pneumoniae causes urinary tract infections, nosocomial pneumonia and intra-abdominal infections. Capsular antigens are considered to be the ultimate virulence determinants. Among 77 capsular serotypes of K. pneumoniae, serotypes K1 and K2 are the most virulent ones in humans. Objectives: We designed a PCR method for detection of capsular serotypes K1 and K2 of K. pneumoniae using genes cps cluster wzc and orf10 which are required for biosynthesis of capsular polysaccharides in K1 and K2 types, respectively. Materials and Methods: We collected 89 K. pneumoniae clinical isolates from the patients of Labafinejad Hospital located in Tehran. Clinical isolates were mostly chosen from urine. We used PCR technique to detect isolates possessing K1 and K2 capsular polysaccharides based on the wzc and orf10 genes which are required for biosynthesis of capsular polysaccharide in K1 and K2 types, respectively. The results of PCR were compared with those obtained by capsular serotyping using Quellung test. Results: Of 89 isolates of K. pneumoniae tested by both techniques, 10 (11.2%) belonged to K1 and 13 (14.6%) belonged to K2 serotypes, respectively. Conclusions: We found that these serotypes are probably important in clinical specimens. PCR was a simple and inexpensive tool for identification of K. pneumoniae clinical isolates of K1 and K2 geno-serotypes.

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Section: Discussionmentioning

confidence: 89%

Identification of Klebsiella pneumoniae K1 and K2 Capsular Types by PCR and Quellung Test

Feizabadi

Raji

Delfani

2013

Jundishapur J Microbiol

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“…The present study demonstrates that K. pneumoniae of K1 serotype is mostly responsible for invasive liver abscess increasingly prevalent in Korea as well as in Taiwan. A Taiwanese study has demonstrated a pathogenic role of the magA gene in liver abscess using molecular Koch's postulates, 12 however, magA is now known as a conserved gene in the serotype-specific region of the K1 capsule gene cluster, 11,37 and K1 capsular polysaccharide per se is considered as one of the essential virulence determinants for the development of invasive liver abscess. 37,38 Recently, rmpA-associated hypermucoviscosity phenotype has also been reported to play an important role in invasive purulent diseases caused by K. pneumoniae.…”

Section: Discussionmentioning

confidence: 99%

“…A Taiwanese study has demonstrated a pathogenic role of the magA gene in liver abscess using molecular Koch's postulates, 12 however, magA is now known as a conserved gene in the serotype-specific region of the K1 capsule gene cluster, 11,37 and K1 capsular polysaccharide per se is considered as one of the essential virulence determinants for the development of invasive liver abscess. 37,38 Recently, rmpA-associated hypermucoviscosity phenotype has also been reported to play an important role in invasive purulent diseases caused by K. pneumoniae. 39 Global differences in the incidence and clinical patterns of community-acquired invasive infections caused by K. pneumoniae has been addressed by a worldwide collaborative study.…”

Section: Discussionmentioning

confidence: 99%

Emerging invasive liver abscess caused by K1 serotype Klebsiella pneumoniae in Korea

Chung¹,

Lee²,

Lee³

et al. 2007

Journal of Infection

237

170

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“…Recently, KLAs have also been reported in Western and other Asian countries (Pope et al, 2011). Although the pathogenic mechanism of KLA remains unknown, several virulence traits including K1 capsular polysaccharides (Fung et al, 2002), magA (Chuang et al, 2006), iron acquisition loci on pLVPK (Tang et al, 2010), as well as type 1 and type 3 fimbriae (Struve et al, 2009;Stahlhut et al, 2012) have been implicated with a role in the pathogenesis.…”

Section: Introductionmentioning

confidence: 99%

PecS regulates the urate-responsive expression of type 1 fimbriae in Klebsiella pneumoniae CG43

et al. 2015

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In the Klebsiella pneumoniae CG43 genome, the divergently transcribed genes coding for PecS, the MarR-type transcription factor, and PecM, the drug metabolite transporter, are located between the type 1 and type 3 fimbrial gene clusters. The intergenic sequence pecO between pecS and pecM contains three putative PecS binding sites and a CpxR box. Electrophoretic mobility shift assay revealed that the recombinant PecS and CpxR could specifically bind to the pecO sequence, and the specific interaction of PecS and pecO could be attenuated by urate. The expression of pecS and pecM was negatively regulated by CpxAR and PecS, and was inducible by exogenous urate in the absence of cpxAR. Compared with CG43S3DcpxAR, the derived mutants CG43S3DcpxARDpecS and CG43S3DcpxARDpecSDpecM exerted similar levels of sensitivity to H 2 O 2 or paraquat, but higher levels of mannose-sensitive yeast agglutination activity and FimA production. The promoter activity and transcript levels of fimA in CG43S3DcpxAR were also increased by deleting pecS. However, no binding activity between PecS and the fimA promoter could be observed. Nevertheless, PecS deletion could reduce the expression of the global regulator HNS and release the negative effect of HNS on FimA expression. In CG43S3DcpxAR, the expression of FimA as well as PecS was inducible by urate, whilst urate-induced FimA expression was inhibited by the deletion of pecS. Taken together, we propose that K. pneumoniae PecS indirectly and negatively regulates the expression of type 1 fimbriae, and the regulation is urateinducible in the absence of CpxAR.

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Genetic Determinants of Capsular Serotype K1 ofKlebsiella pneumoniaeCausing Primary Pyogenic Liver Abscess

Abstract: The operon containing magA is responsible for capsular serotype K1 of K. pneumoniae. Several loci in the operon are unique determinants of K1 strains.

Cited by 199 publications

References 36 publications

Identification of Klebsiella pneumoniae K1 and K2 Capsular Types by PCR and Quellung Test

Identification of Klebsiella pneumoniae K1 and K2 Capsular Types by PCR and Quellung Test

Emerging invasive liver abscess caused by K1 serotype Klebsiella pneumoniae in Korea

PecS regulates the urate-responsive expression of type 1 fimbriae in Klebsiella pneumoniae CG43

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