Genetic variability of mutans streptococci revealed by wide whole-genome sequencing

BMC Genomics

Research Article

Anke Rheinberg¹  Georg Conrads¹  Irene Wagner-Döbler²  Helena Sztajer²  Michael Reck²  Wei Wang³  Lifu Song³  An-Ping Zeng³ 

[1] Division of Oral Microbiology and Immunology, Department of Operative and Preventive Dentistry & Periodontology, RWTH Aachen University, RWTH Aachen, Germany;Helmholtz-Centre for Infection Research, Group Microbial Communication, Division of Microbial Pathogenesis, Inhoffenstr. 7, 38124, Braunschweig, Germany;Institute of Bioprocess and Biosystems, Technical University Hamburg Harburg, Hamburg Harburg, Germany;

关键词: Mutans Streptococci;    Streptococcus Mutans;    Streptococcus Ratti;    Streptococcus Sobrinus;    Comparative Genomics;    Core-genome;    Pan-genome;    Pathogenicity;    Lactate Oxidase;    Metabolic Network;   

DOI  :  10.1186/1471-2164-14-430

 received in 2013-02-10, accepted in 2013-06-12,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundMutans streptococci are a group of bacteria significantly contributing to tooth decay. Their genetic variability is however still not well understood.ResultsGenomes of 6 clinical S. mutans isolates of different origins, one isolate of S. sobrinus (DSM 20742) and one isolate of S. ratti (DSM 20564) were sequenced and comparatively analyzed. Genome alignment revealed a mosaic-like structure of genome arrangement. Genes related to pathogenicity are found to have high variations among the strains, whereas genes for oxidative stress resistance are well conserved, indicating the importance of this trait in the dental biofilm community. Analysis of genome-scale metabolic networks revealed significant differences in 42 pathways. A striking dissimilarity is the unique presence of two lactate oxidases in S. sobrinus DSM 20742, probably indicating an unusual capability of this strain in producing H2O2 and expanding its ecological niche. In addition, lactate oxidases may form with other enzymes a novel energetic pathway in S. sobrinus DSM 20742 that can remedy its deficiency in citrate utilization pathway.Using 67 S. mutans genomes currently available including the strains sequenced in this study, we estimates the theoretical core genome size of S. mutans, and performed modeling of S. mutans pan-genome by applying different fitting models. An “open” pan-genome was inferred.ConclusionsThe comparative genome analyses revealed diversities in the mutans streptococci group, especially with respect to the virulence related genes and metabolic pathways. The results are helpful for better understanding the evolution and adaptive mechanisms of these oral pathogen microorganisms and for combating them.

【 授权许可】

Unknown   
© Song et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.