Purification of a novel fructosyltransferase from Lactobacillus reuteri strain 121 and characterization of the levan produced

Fructosyltransferase (FTF) enzymes have been characterized from various Gram-positive bacteria, but not from Lactobacillus sp. In a screening of 182 lactobacilli for polysaccharide production only one strain, Lactobacillus reuteri strain 121, was found to produce a fructan being a levan. Here we report the first-time identification and biochemical characterization of a Lactobacillus FTF enzyme. When incubated with sucrose the enzyme produced a levan that is identical to that produced by Lb. reuteri strain 121 cells.