title: Both clades of the epidemic KPC-producing Klebsiella pneumoniae clone ST258 share a modified galactan O-antigen type.
abstract: Klebsiella pneumoniae ST258 is a globally disseminated, extremely drug resistant, nosocomial clone with limited treatment options. We show that the vast majority of ST258 isolates express modified d-galactan-I lipopolysaccharide O-antigen, termed hereinafter as D-galactan-III. The genetic determinant required for galactan-III synthesis was identified as a distinct operon adjacent to the rfb (wb) locus encoding D-galactan-I synthesis. The three genes within the operon encode predicted glycosyltransferases. Testing an isogenic transformant pair revealed that expression of D-galactan-III, in comparison to D-galactan-I, conferred improved survival in the presence of human serum. Eighty-three percent of the more than 200 ST258 draft genome sequences currently available carries the corresponding operon and hence these isolates are predicted to express galactan-III antigens. A D-galactan-III specific monoclonal antibody (mAb) was shown to bind to extracted LPS from a panel of ST258 isolates. The same mAb confirmed accessibility of galactan-III in surface staining of ST258 irrespective of the distinct capsular antigens expressed by both clades described previously. Based on these data, the galactan-III antigen may represent an attractive target for active and passive immunization approaches against K. pneumoniae ST258.
authors.affiliation: Arsanis Biosciences GmbH, Vienna, Austria.
authors.forename: Valéria
authors.initials: V
authors.lastname: Szijártó
authors.affiliation: Arsanis Biosciences GmbH, Vienna, Austria.
authors.forename: Luis Miguel
authors.initials: LM
authors.lastname: Guachalla
authors.affiliation: Arsanis Biosciences GmbH, Vienna, Austria.
authors.forename: Katharina
authors.initials: K
authors.lastname: Hartl
authors.affiliation: Arsanis Biosciences GmbH, Vienna, Austria.
authors.forename: Cecília
authors.initials: C
authors.lastname: Varga
authors.affiliation: Arsanis Biosciences GmbH, Vienna, Austria.
authors.forename: Pallavi
authors.initials: P
authors.lastname: Banerjee
authors.affiliation: Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland.
authors.forename: Katarina
authors.initials: K
authors.lastname: Stojkovic
authors.affiliation: Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Kaszowska
authors.affiliation: Arsanis Biosciences GmbH, Vienna, Austria.
authors.forename: Eszter
authors.initials: E
authors.lastname: Nagy
authors.affiliation: Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Lukasiewicz
authors.affiliation: Arsanis Biosciences GmbH, Vienna, Austria.
authors.forename: Gábor
authors.initials: G
authors.lastname: Nagy
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000954:Antigens, Surface / Q000276:immunology; D003001:Cloning, Molecular; D000939:Epitopes / Q000276:immunology; D005260:Female; D005685:Galactans / Q000145:classification / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006825:Hybridomas; D007711:Klebsiella pneumoniae / Q000145:classification / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D008070:Lipopolysaccharides / Q000276:immunology; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008807:Mice, Inbred BALB C; D019081:O Antigens / Q000032:analysis / Q000235:genetics / Q000276:immunology*; D009876:Operon / Q000235:genetics; D014774:Virulence
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D000939:Epitopes; D005685:Galactans; D008070:Lipopolysaccharides; D019081:O Antigens
keywords: Klebsiella pneumoniae ST258; LPS O-antigen; Monoclonal antibody; Serotype O2; d-Galactan-I; d-Galactan-III