Glycosyltransferases play a pivotal role in regulating biofilm formation and pathogenicity in Streptococcus suis

The crucial role of biofilm formation in the persistent infection and pathogenicity of Streptococcus suis compels researchers to delve into the mechanism underlying biofilm formation by S. suis. A previous study based on transposon screening indicated the potential impact of glycosyltransferases on S. suis biofilm formation. In this study, we characterized the major components of S. suis biofilm matrix and further elucidated the factors involved in glycosyltransferase-regulated biofilm formation by constructing a gene deletion strain, which involved the regulation of S. suis extracellular matrix, extracellular quorum-sensing signaling molecules and intracellular C-di-AMP, cell surface properties and bacterial energy metabolism. Additionally, the involvement of glycosyltransferases in the regulation of capsular polysaccharide content, composition, and structure of S. suis has been unveiled. Finally, the regulatory role of glycosyltransferases in the virulence of S. suis was elucidated based on in vitro and in vivo infection assessments, loss of glycosyl transferase function weaken the virulence of S. suis.