An Overview of Functional Genomics and Relevance of Glycosyltransferases in Exopolysaccharide Production by Lactic Acid Bacteria

Abstract

There are many reports on exopolysaccharides of lactic acid bacteria (LAB EPS) such as isolation, production and applications. The LAB EPS have been proved to exhibit significantly improved texture and rheological properties in order to prevent syneresis of fermented foods. Furthermore, they are known to have many biological properties such as mouthwatering flavors, antioxidant activity, cholesterol lowering and antimicrobial activities. Considering their GRAS status, LAB EPS need to be explored for better titre and improved biological properties, where strain improvement by genetic engineering has a major role for making tailor-made EPS. The genetic overview of the EPS production by LAB is an auxiliary area of interest as the process and the biosynthetic pathway involves numerous genes and their proteins. Among them Glycosyltransferases (gtfs) are the key enzymes involved in EPS biosynthesis. Current knowledge of gtfs of LAB and its manipulation is limited. The present review spotlights the importance of glycosyltransferases and their specific role on the biosynthesis of LAB EPS and addresses the functionality and applicability of these enzymes and their products. It enfold the available literature including some patents in recent past to underline the fact that glycosyltransferases are un-reluctantly the key proteins involved in the EPS biosynthesis.