Klebsiella pneumoniae strain KK207-2 was isolated in 2010 froma bloodstreaminfection of an inpatient at an Italian hospital. It was previously found to produce the KPC-2 carbapenemase and to belong to clade 1 of sequence type 258. Genotyping of the conserved wzi and wzc genes from strain KK207-2 yielded contrasting results: the wzc-based method assigned the cps207–2 to a new K-type, while the wzi-based method assigned it to the known K41 K-type. In order to resolve this contradiction, the capsular polysaccharide of K. pneumoniae KK207-2 was purified and its structure determined by using GLC-MS of appropriate carbohydrate derivatives, ESI-MS of both partial hydrolysis and Smith degradation derived oligosaccharides, andNMR spectroscopy of oligosaccharides, and the lithium degraded, native and de-O-acetylated polysaccharide. All the collected data demonstrated the following repeating unit for the K. pneumoniae KK207-2 capsular polysaccharide: OAc 6 [3)-β-D-Gal-(1-4)-β-D-Glc-(1-]n 4 I 1 β-D-Glcp-(1-6)-α-D-Glcp-(1-4)-β-D-GlcpA-(1-6)-α-D-Glcp The polysaccharide contains about 0.60 acetyl groups per repeating unit on C6 of the Gal residue. The reactions catalysed by each glycosyltransferase in the cpsKK207-2 gene cluster were assigned on the basis of structural homology with other Klebsiella K antigens.

Structure of the capsular polysaccharide of the KPC-2-producing Klebsiella pneumoniae strain KK207-2 and assignment of the glycosyltransferases functions

Bellich, Barbara;Ravenscroft, Neil;Lagatolla, Cristina;Cescutti, Paola
2019-01-01

Abstract

Klebsiella pneumoniae strain KK207-2 was isolated in 2010 froma bloodstreaminfection of an inpatient at an Italian hospital. It was previously found to produce the KPC-2 carbapenemase and to belong to clade 1 of sequence type 258. Genotyping of the conserved wzi and wzc genes from strain KK207-2 yielded contrasting results: the wzc-based method assigned the cps207–2 to a new K-type, while the wzi-based method assigned it to the known K41 K-type. In order to resolve this contradiction, the capsular polysaccharide of K. pneumoniae KK207-2 was purified and its structure determined by using GLC-MS of appropriate carbohydrate derivatives, ESI-MS of both partial hydrolysis and Smith degradation derived oligosaccharides, andNMR spectroscopy of oligosaccharides, and the lithium degraded, native and de-O-acetylated polysaccharide. All the collected data demonstrated the following repeating unit for the K. pneumoniae KK207-2 capsular polysaccharide: OAc 6 [3)-β-D-Gal-(1-4)-β-D-Glc-(1-]n 4 I 1 β-D-Glcp-(1-6)-α-D-Glcp-(1-4)-β-D-GlcpA-(1-6)-α-D-Glcp The polysaccharide contains about 0.60 acetyl groups per repeating unit on C6 of the Gal residue. The reactions catalysed by each glycosyltransferase in the cpsKK207-2 gene cluster were assigned on the basis of structural homology with other Klebsiella K antigens.
File in questo prodotto:
File Dimensione Formato  
IJBIOMAC_2018_7171_Revision 2_V0.pdf

Open Access dal 23/02/2020

Descrizione: articolo principale
Tipologia: Bozza finale post-referaggio (post-print)
Licenza: Creative commons
Dimensione 2.2 MB
Formato Adobe PDF
2.2 MB Adobe PDF Visualizza/Apri
1-s2.0-S0141813018373884-main.pdf

Accesso chiuso

Tipologia: Documento in Versione Editoriale
Licenza: Copyright Editore
Dimensione 1.59 MB
Formato Adobe PDF
1.59 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
1-s2.0-S0141813018373884-mmc1.pdf

Accesso chiuso

Descrizione: Supplementary material
Tipologia: Altro materiale allegato
Licenza: Copyright Editore
Dimensione 772.25 kB
Formato Adobe PDF
772.25 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11368/2941805
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 13
  • ???jsp.display-item.citation.isi??? 11
social impact