Quorum sensing of Streptococcus mutans is activated by Aggregatibacter actinomycetemcomitans and by the periodontal microbiome

BMC Genomics

Research Article

Manfred Rohde¹  Michael Jarek²  Sabin Bhuju²  Zhi-Luo Deng³  Irene Wagner-Döbler³  Jürgen Tomasch³  Helena Sztajer³  Szymon P. Szafrański⁴ 

[1] Central Facility for Microscopy, Helmholtz Centre for Infection Research, Braunschweig, Germany;Genome Analytics, Helmholtz Centre for Infection Research, Braunschweig, Germany;Microbial Communication, Helmholtz-Center for Infection Research, Braunschweig, Germany;Microbial Communication, Helmholtz-Center for Infection Research, Braunschweig, Germany;Present address: Hannover Medical School (MHH), Hannover, Germany;

关键词: Quorum Sense;    Regulon;    Histidine Kinase;    Artificial Saliva;    Log2 Fold Change;   

DOI  :  10.1186/s12864-017-3618-5

 received in 2016-11-17, accepted in 2017-03-10,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundThe oral cavity is inhabited by complex microbial communities forming biofilms that can cause caries and periodontitis. Cell-cell communication might play an important role in modulating the physiologies of individual species, but evidence so far is limited.ResultsHere we demonstrate that a pathogen of the oral cavity, Aggregatibacter actinomycetemcomitans (A. act.), triggers expression of the quorum sensing (QS) regulon of Streptococcus mutans, a well-studied model organism for cariogenic streptococci, in dual-species biofilms grown on artificial saliva. The gene for the synthesis of the QS signal XIP is essential for this interaction. Transcriptome sequencing of biofilms revealed that S. mutans up-regulated the complete QS regulon (transformasome and mutacins) in the presence of A. act. and down-regulated oxidative stress related genes. A.act. required the presence of S. mutans for growth. Fimbriae and toxins were its most highly expressed genes and up-regulation of anaerobic metabolism, chaperones and iron acquisition genes was observed in co-culture. Metatranscriptomes from periodontal pockets showed highly variable levels of S. mutans and low levels of A. act.. Transcripts of the alternative sigma-factor SigX, the key regulator of QS in S. mutans, were significantly enriched in periodontal pockets compared to single cultures (log2 4.159, FDR ≤0.001, and expression of mutacin related genes and transformasome components could be detected.ConclusionThe data show that the complete QS regulon of S. mutans can be induced by an unrelated oral pathogen and S. mutans may be competent in oral biofilms in vivo.

【 授权许可】

CC BY   
© The Author(s). 2017