Role of Streptococcus mutans two-component systems in antimicrobial peptide resistance in the oral cavity

Abstract

SummaryApproximately 100 trillion microorganisms exist in the oral cavity. For the commensal bacteria of the oral cavity, it is important to adapt to environmental stimuli, including human- or bacteria-derived antimicrobial agents. Recently, bacterial-specific signal transduction regulatory systems, called two-component systems (TCSs), which appear to be focused on sensing and adapting to the environment, were discovered. Streptococcus mutans is an oral commensal bacteria and is also known as a cariogenic bacteria. Although the virulence factors of S. mutans have been well demonstrated, the mechanism underlying the adaptation of the species to the oral cavity is poorly understood. S. mutans UA159 has 15 sets of TCSs. Among them, several have been demonstrated to be involved in acid tolerance, competence and biofilm formation. Recently, together with our findings, it was demonstrated that 5 TCSs were involved in resistance to antimicrobial agents. Furthermore, another TCS was associated with the production of bacteriocin. Six of 15 TCSs are associated with antimicrobial agents, implying that S. mutans can survive in the oral cavity by resisting various antimicrobial peptides.In this review, we highlight the role of antimicrobial peptides in the oral cavity.

Analysis of Porcine Model of Fecal-Induced Peritonitis Reveals the Tropism of Blood Microbiome

“…Two-component systems, each composed of a histidine kinase and a response regulator, are major bacterial signaling pathways that sense environmental cues ( Mascher et al., 2006 ; Mattos-Graner and Duncan, 2017 ), such as pH ( Gao and Lynn, 2005 ; Liu and Burne, 2009 ) and oxidative stress ( Ortiz de Orué Lucana et al., 2012 ). They are also tightly linked to bacterial responses to the host immune system ( Barrett and Hoch, 1998 ; Kawada-Matsuo and Komatsuzawa, 2017 ). Therefore, it is likely that cells in the microbiome would utilize these systems to survive.…”

Roles of Two-Component Regulatory Systems in Antibiotic Resistance

“…Several Streptococcus species including S. pyogenes, S. mutans and S. pneumoniae utilize the TCS VicKR, which upregulates biofilm formation in response to an as-yet-undetermined environmental signal [137,[206][207][208]. In S. mutans, LiaSR also increases biofilm formation in response to cell envelope stress and can directly react to the antibiotic bacitracin [135,137]. At least two other TCSs, ComDE and hk11/rr11 in S. mutans, also appear to function in the formation of biofilm [79,80,132].…”

Analysis of the blood microbiome in a porcine model of fecal-induced peritonitis

“…The two-component system, which is composed of a histidine kinase and a response regulator, is a major bacterial central signaling pathways that senses environmental cues [43,44] such as pH [45,46] and oxidative stress [47]. It is also tightly linked to bacterial responses to the host immune system [48,49]; therefore, it is likely that cells in the microbiome would activate to survive.…”