Capsular-type prediction by phylogenetic tree of glycosyltransferase gene polymorphism in Streptococcus pneumoniae
Yuka Tomita1,2, Akira Okamoto2, Keiko Yamada2, Testuya Yagi3, Yoshinori Hasegawa4, Michio Ohta2
1Department of Infectious Disease, Nagoya University Hospital, 2Department of Bacteriology, Nagoya University Graduate School of Medicine, 3Center of National University Hospital for Infection Control, Nagoya University Hospital, 4Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya, Japan
Abstract: Streptococcus pneumoniae can cause severe infections among children and the elderly. Molecular capsule typing is being investigated extensively as a replacement of conventional serotyping using antisera. We focused on the glycosyltransferase (GT) genes in the capsular polysaccharide synthesis (cps) gene cluster of S. pneumoniae for classification of capsular types. The Sanger Institute provided sequences of the cps loci of 90 serotypes of S. pneumoniae. Each cps locus contained 1–6 putative GT genes per strain, for a total of 352 GT genes. Phylogenetic analysis of GT gene polymorphisms distinguished 90 serotypes into 64 phylogenetic groups. However, the sequence data contained only one sample from each serotype. Therefore, we selected six clinical isolates belonging to serogroup 6 and seven clinical isolates belonging to serotype 19F by antisera and sequenced GT genes. From phylogenetic analysis, these sequences were very similar to those of the Sanger Institute, and we can use GT genes as serotype-specific genes.
Keywords: Streptococcus pneumoniae, phylogenetic tree, glycosyltransferase gene
© 2011 The Author(s). This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.