Extracellular polysaccharide synthesis by members of the genus Lactobacillus: conditions for formation and accumulation.

Members of the genus LactobacilZus were examined for their ability to synthesize extracellular polysaccharide from sucrose. Strains physiologically similar to L. pastorianus synthesized a glucan. Other strains liberated a complex polysaccharide which contained mannose and glucose. Variants of the glucan-producing strains occurred spontaneously and these lacked the capacity to synthesize glucan ; however, extracts of these bacilli contained glucansucrase and invertase. Manometric studies indicated that the latter enzyme functioned in the sucrose metabolism of these non-glucan producing variants.