Department of Physiological Sciences, Piracicaba Dental School, UNICAMP, CP 52, CEP 13414-903, Piracicaba, SP, Brazil.
Int J Biol Macromol. 2010 Jun;46(5):551-4. doi: 10.1016/j.ijbiomac.2010.01.018. Epub 2010 Feb 6.
Extracellular polysaccharide is a virulence factor of the most cariogenic bacteria, Streptococcus mutans. We describe a procedure for chemical analysis of this polysaccharide of S. mutans, using a well-known glucan synthesized by purified enzymes of cariogenic streptococci. Soluble and insoluble glucan from glucosyltransferase D and B respectively, were prepared and analyzed by nuclear magnetic resonance spectroscopy and methylation. Soluble alpha-glucan contained 60% of (1-->6)-linkages and 17% of branching while insoluble alpha-glucan was composed of 57% of (1-->3)- and 28% of (1-->6)-linkages with 8% branching. The described procedure could be important focusing future studies on in vivo biofilm.
细胞外多糖是最具致龋性的细菌——变形链球菌的毒力因子。我们描述了一种化学分析方法,用于分析变形链球菌的这种多糖,使用的是由致龋链球菌的纯化酶合成的一种已知的葡聚糖。分别从葡糖基转移酶 D 和 B 中制备并分析了可溶性和不溶性葡聚糖,通过核磁共振波谱和甲基化分析。可溶性α-葡聚糖含有 60%的(1→6)键和 17%的支链,而不溶性α-葡聚糖由 57%的(1→3)键和 28%的(1→6)键以及 8%的支链组成。所描述的方法可能对未来的体内生物膜研究非常重要。