Two glycosyl transferase 2 genes from the gram-positive bacterium Clostridium ventriculi encode (1,3;1,4)-β-D-glucan synthases

Carbohydr Polym. 2024 Oct 15:342:122394. doi: 10.1016/j.carbpol.2024.122394. Epub 2024 Jun 14.

Abstract

The exopolysaccharides of the Gram-positive bacterium Romboutsia ilealis have recently been shown to include (1,3;1,4)-β-D-glucans. In the present study, we examined another Clostridia bacterium Clostridium ventriculi that has long been considered to contain abundant amounts of cellulose in its exopolysaccharides. We treated alcohol insoluble residues of C. ventriculi that include the exopolysaccharides with the enzyme lichenase that specifically hydrolyses (1,3;1,4)-β-D-glucans, and examined the oligosaccharides released. This showed the presence of (1,3;1,4)-β-D-glucans, which may have previously been mistaken for cellulose. Through genomic analysis, we identified the two family 2 glycosyltransferase genes CvGT2-1 and CvGT2-2 as possible genes encoding (1,3;1,4)-β-D-glucan synthases. Gain-of-function experiments in the yeast Saccharomyces cerevisiae demonstrated that both of these genes do indeed encode (1,3;1,4)-β-D-glucan synthases.

Keywords: Cellulose; Exopolysaccharides; Romboutsia ilealis; Saccharomyces cerevisiae; Transgenic expression.

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Clostridium* / enzymology
  • Clostridium* / genetics
  • Glucosyltransferases / genetics
  • Glucosyltransferases / metabolism
  • Glycoside Hydrolases / genetics
  • Glycoside Hydrolases / metabolism
  • Glycosyltransferases* / genetics
  • Glycosyltransferases* / metabolism
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics
  • beta-Glucans / metabolism

Substances

  • Glycosyltransferases
  • licheninase
  • beta-Glucans
  • Bacterial Proteins
  • Glycoside Hydrolases
  • Glucosyltransferases