Maxon M E, Wigboldus J, Brot N, Weissbach H
Roche Research Center, Roche Institute of Molecular Biology, Nutley, NJ 07110-1199.
Proc Natl Acad Sci U S A. 1990 Sep;87(18):7076-9. doi: 10.1073/pnas.87.18.7076.
The Escherichia coli metR gene has been sequenced. The sequence predicts a protein of 317 amino acids and a calculated molecular weight of 35,628. This is about 15% larger than the protein from Salmonella typhimurium reported previously [Plamann, L.S. & Stauffer, G.V. (1987) J. Bacteriol. 169, 3932-3937]. The protein is a homodimer and contains a leucine zipper motif characteristic of many eukaryotic DNA-binding proteins. Replacement of two of the leucines in the leucine zipper region of the MetR protein, or substitution of proline for one of the leucines, results in loss of biological activity of the protein. In addition, truncation studies have identified a region on MetR that may be involved in the homocysteine activation of metE expression.
大肠杆菌的metR基因已被测序。该序列预测的蛋白质有317个氨基酸，计算分子量为35628。这比之前报道的鼠伤寒沙门氏菌的蛋白质大约大15%[普拉曼，L.S.和施陶弗，G.V.（1987年）《细菌学杂志》169，3932 - 3937]。该蛋白质是同型二聚体，包含许多真核生物DNA结合蛋白特有的亮氨酸拉链基序。在MetR蛋白的亮氨酸拉链区域替换两个亮氨酸，或将其中一个亮氨酸替换为脯氨酸，会导致该蛋白质丧失生物活性。此外，截短研究已经确定了MetR上一个可能参与metE表达的高半胱氨酸激活的区域。
