van Kranenburg R, van Swam I I, Marugg J D, Kleerebezem M, de Vos W M
Microbial Ingredients Section, NIZO Food Research, 6710 BA Ede, The
J Bacteriol. 1999 Jan;181(1):338-40. doi: 10.1128/JB.181.1.338-340.1999.
We used homologous and heterologous expression of the glycosyltransferase genes of the Lactococcus lactis NIZO B40 eps gene cluster to determine the activity and substrate specificities of the encoded enzymes and established the order of assembly of the trisaccharide backbone of the exopolysaccharide repeating unit. EpsD links glucose-1-phosphate from UDP-glucose to a lipid carrier, EpsE and EpsF link glucose from UDP-glucose to lipid-linked glucose, and EpsG links galactose from UDP-galactose to lipid-linked cellobiose. Furthermore, EpsJ appeared to be involved in EPS biosynthesis as a galactosyl phosphotransferase or an enzyme which releases the backbone oligosaccharide from the lipid carrier.
我们利用乳酸乳球菌NIZO B40 eps基因簇的糖基转移酶基因进行同源和异源表达，以确定所编码酶的活性和底物特异性，并确定了胞外多糖重复单元三糖主链的组装顺序。EpsD将来自UDP-葡萄糖的葡萄糖-1-磷酸连接到脂质载体上，EpsE和EpsF将来自UDP-葡萄糖的葡萄糖连接到脂质连接的葡萄糖上，EpsG将来自UDP-半乳糖的半乳糖连接到脂质连接的纤维二糖上。此外，EpsJ似乎作为半乳糖基磷酸转移酶或一种从脂质载体释放主链寡糖的酶参与EPS生物合成。
