Dextran polysaccharide produced by Gtf180-ΔN of Lactobacillus reuteri 180 mutant L940F
The glucansucrase of Lactobacillusreuteri 180 catalyzes the synthesis of a diversity of α-glucans from sucrose. An enzyme mutation of Leu940 in domain B significantly changed the linkage and reaction specificity. Compared with the GTF180-ΔN wild type, the GTF180-ΔN L940F mutant has an increased percentage of α(1→6) linkages and a decreased percentage of α(1→3) linkages in the product. Furthermore, the mutant enzyme has an increased polysaccharide synthesis.