Kawamukai M, Utsumi R, Takeda K, Higashi A, Matsuda H, Choi Y L, Komano T
Laboratory of Applied Microbiology, Faculty of Agriculture, Shimane University, Matsue, Japan.
J Bacteriol. 1991 Apr;173(8):2644-8. doi: 10.1128/jb.173.8.2644-2648.1991.
We have cloned at least 12 different Escherichia coli genes which enable strain MK2001 to use maltose. The genes were designated sfs1 through sfs12 (sugar fermentation stimulation). Previously, one (sfs7) of them was mapped at 65 min on the E. coli chromosome and identified as nlp, which has high homology to repressor protein (Ner) of Mu phage, which contains a putative DNA binding region (Y.-L. Choi, T. Nishida, M. Kawamukai, R. Utsumi, H. Sakai, and T. Komano, J. Bacteriol. 171:5222-5225, 1989). In this study, another gene (sfs1) located at 3.5 min was newly found and analyzed. The nucleotide sequence of sfs1 encoded a protein of 234 amino acids (molecular mass, 26,227 Da) which also has a putative DNA binding domain. Overexpression of the sfs1 gene in MK2001 resulted in a 10-fold increase of amylomaltase, which was still dependent on MalT. These results suggest that Sfs1 could be a new regulatory factor involved in maltose metabolism.
我们已经克隆了至少12个不同的大肠杆菌基因，这些基因能使MK2001菌株利用麦芽糖。这些基因被命名为sfs1至sfs12（糖发酵刺激）。此前，其中一个基因（sfs7）被定位在大肠杆菌染色体的65分钟处，并被鉴定为nlp，它与Mu噬菌体的阻遏蛋白（Ner）具有高度同源性，后者含有一个假定的DNA结合区域（Y.-L. Choi、T. Nishida、M. Kawamukai、R. Utsumi、H. Sakai和T. Komano，《细菌学杂志》171:5222 - 5225，1989年）。在本研究中，新发现并分析了另一个位于3.5分钟处的基因（sfs1）。sfs1的核苷酸序列编码了一个由234个氨基酸组成的蛋白质（分子量为26,227道尔顿），该蛋白质也具有一个假定的DNA结合结构域。sfs1基因在MK2001中的过表达导致支链淀粉酶增加了10倍，其增加仍依赖于MalT。这些结果表明，Sfs1可能是参与麦芽糖代谢的一种新的调节因子。
