REGULATION OF SUGAR TRANSPORT AND METABOLISM IN LACTIC ACID BACTERIA

1.依赖氨基酸的糖运输系统已在 梭杆菌的各种种类。 2.磷酸烯醇式丙酮酸(PEP)：依赖的蔗糖磷酸转移酶 该系统已在桑叶霉中发现。第一次提纯 这种有机体中的依赖于ATP的果糖激酶已经实现，并且 N-末端已确定。 3.对蔗糖6-磷酸水解酶进行了纯化，得到了均一的酶 乳酸乳球菌，其结构基因(Scra)已定位于 染色体编码的转座子Tn5306。 4.乳酸乳杆菌的果糖激酶也已纯化至均一，以及 ScrK基因也定位在转座子Tn5306上，与SCRA相近。 5.转座子Tn5306是第一个被描述的“代谢”转座子 在乳酸菌中。这么大(约50-100kb？)“移动”DNA片段 编码N5-(CE)鸟氨酸合成酶、蔗糖转运和 分解代谢、乳链菌素合成和抗性，以及转座酶基因。

1. Amino acid-dependent sugar transport systems have been identified in various species of Fusobacteria. 2. The phosphoenolpyruvate (PEP): dependent sucrose phosphotransferase system has been found in F. mortiferum. The first purification of the ATP-dependent fructokinase from this organism has been achieved, and the N-terminal has been determined. 3. Sucrose 6-phosphate hydrolase has been purified to homogeneity from Lactococcus lactis, and the structural gene (scrA) has been localized on the chromosomally-encoded transposon, Tn5306. 4. Fructokinase from L.lactis has also been purified to homogeneity, and the scrK gene is also localized on transposon Tn5306, close to scrA. 5. Transposon Tn5306 is the first "metabolic" transposon to be described in lactic acid bacteria. This large (~50-100kb?) fragment of 'mobile' DNA encodes genes for N5-(CE)ornithine synthase, sucrose transport and catabolism, nisin synthesis and resistance, and a transposase gene.