LAUSR

Levansucrase gene (LmLEVS) was cloned from Leuconostoc mesenteroides MTCC 10508. The heterologous expression and purification of the truncated (TrLmLEVS) gene, lacking the N-terminal signal peptide, was performed in Escherichia coli. The recombinant enzyme (TrLmLEVS) was physico-kinetically characterized using sucrose as substrate. TrLmLEVS exhibited the maximum activity at pH 6 and temperature 30 °C. Thin layer chromatography and high performance liquid chromatography analyses unveiled the biosynthesis of fructooligosaccharides and levan by TrLmLEVS using sucrose as substrate. The catalytically synthesized polymer was characterized by Fourier-Transform Infrared Spectroscopy and Nuclear Magnetic Resonance analyses, confirming it as levan. TrLmLEVS was capable of catalyzing the transformation of raffinose-derived molecules, besides sucrose, into fructans. Further, TrLmLEVS was employed for the genesis of non-digestible fructans from sucrose-containing feedstocks like table sugar, jaggery, cane molasses, and sweet sorghum juice. The results suggest that Leu. mesenteroides MTCC 10508 levansucrase is a potential candidate for the production of levan-type biomolecules in plant-based food products.