Acetylation of glucosyltransferases regulates Streptococcus mutans biofilm formation and virulence

• DOI: 10.1371/journal.ppat.1010134
• Publication Date: 2021-12-03T18:29:36Z
• Authors: Qizhao Ma; Yangyang Pan; Yang Chen; Shuxing Yu; Jun Huang; Yaqi Liu; Tao Gong; Jing Zou; Yuqing Li
• Keywords: Glucosyltransferases

Lysine acetylation is a frequently occurring post-translational modification (PTM), emerging as an important metabolic regulatory mechanism in prokaryotes. This process achieved enzymatically by the protein acetyltransferase (KAT) to specifically transfer acetyl group, or non-enzymatically direct intermediates (acetyl phosphate acetyl-CoA). Although lysine of glucosyltransferases (Gtfs), virulence factor Streptococcus mutans , was reported our previous study, KAT has not been identified. Here, we believe that ActG can acetylate Gtfs enzymatic mechanism. By overexpressing 15 KATs S . synthesized water-insoluble extracellular polysaccharides (EPS) and biofilm biomass were measured, ( actG ) The in-frame deletion mutant constructed validate function results showed could negatively regulate EPS synthesis formation. We used mass spectrometry (MS) identify GtfB GtfC possible substrates ActG. also demonstrated vitro assays, indicating increase levels decrease their activities. further found expression level part explained differences clinically isolated strains. Moreover, overexpression attenuated its cariogenicity rat caries model. Taken together, study induce providing insights into bacterial pathogenicity.