β-glucan biosynthesis in Propionibacterium freudenreichii correlates with the expression level of gtf, a unique polysaccharide synthase encoding gene
Résumé
The propionibacteria are considered as food-grade and are essential as ripening starter in Swiss-type cheese. Some strains of Propionibacterium freudenreichii (PF) are also considered as potential probiotic organisms. Recently we identified an EPS encoding gene gtf involved in the biosynthesis of a (1→3,1→2)-β-D-glucan polysaccharide in PF (Deutsch et al., 2008). The aim of this work was to detect the presence of this polysaccharide, to study the expression of gtf, and to understand the role of the promoting region in the expression of gtf.