Structure of Genetic Loci for Capsular Polysaccharide Biosynthesis in <i>Streptococcus parauberis</i> isolated from Japanese flounder

Abstract

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Comparative genomics of Streptococcus parauberis: new target for molecular identification of serotype III

“…These structures play an important role in pathogenicity, immune system escape, serum resistance, inflammation, adhesion, biofilm formation, and antigenicity, which may be used for bacterial serotyping (Okura et al 2013;Rochat et al 2017). The diversity of capsular polysaccharide (CPS) structure of S. parauberis, due to a variety of sugars and glycosidic linkages, led to the description of different serotypes designated as types I, II, and III (Kanai et al 2009;Kanai et al 2015;Tu et al 2015a;. Serotype I was further subdivided into three subtypes, designated Ia, Ib, and Ic (Kanai et al 2015;Tu et al 2015a).…”

“…The diversity of capsular polysaccharide (CPS) structure of S. parauberis, due to a variety of sugars and glycosidic linkages, led to the description of different serotypes designated as types I, II, and III (Kanai et al 2009;Kanai et al 2015;Tu et al 2015a;. Serotype I was further subdivided into three subtypes, designated Ia, Ib, and Ic (Kanai et al 2015;Tu et al 2015a). S. parauberis isolates agglutinating with antibodies of serotypes I and II were also described and designated as non-typable strains (Kanai et al 2015;Tu et al 2015a).…”

“…Serotype I was further subdivided into three subtypes, designated Ia, Ib, and Ic (Kanai et al 2015;Tu et al 2015a). S. parauberis isolates agglutinating with antibodies of serotypes I and II were also described and designated as non-typable strains (Kanai et al 2015;Tu et al 2015a).…”

“…The genes responsible for the synthesis of CPS are typically clustered in a single locus (locus cps) on the chromosome (Okura et al 2013;Tu et al 2015a). The genetic structure of the loci cps in S. parauberis has been determined in serotypes I and II (Tu et al 2015a). In these serotypes a cassette-like structure was observed, in which the conserved regions flanked serotype-specific genes.…”

“…cpsB, cpsC, and cpsD) and one processing gene (cpsE) were found, while at the conserved 3′ end, one regulatory gene (cpsQ) and one hypothetical gene were found. The middle region (variable region) of the locus cps comprises genes encoding enzymes such as glycosyltransferases, acetyltransferases, aminotransferases, and modifying enzymes (Tu et al 2015a).…”