2 PERIPLASMIC TRANSPORT PROTEINS WHICH INTERACT WITH A COMMON MEMBRANE-RECEPTOR SHOW EXTENSIVE HOMOLOGY - COMPLETE NUCLEOTIDE-SEQUENCES
2 PERIPLASMIC TRANSPORT PROTEINS WHICH INTERACT WITH A COMMON MEMBRANE-RECEPTOR SHOW EXTENSIVE HOMOLOGY - COMPLETE NUCLEOTIDE-SEQUENCES
复制标题
DOI：
10.1073/pnas.78.10.6038
复制
发表时间：
1981-01-01
期刊：
影响因子：
--
通讯作者：
AMES, GFL
中科院分区：
文献类型：
--
作者：
HIGGINS, CF;AMES, GFL
鼠伤寒沙门氏菌的hisJ和argT基因编码2种周质结合蛋白，J和LAO，它们分别参与组氨酸和精氨酸的转运，并且与共同的膜结合组分P蛋白相互作用。测定了这2个基因的全核苷酸序列。这2个基因显示出广泛的同源性（70%），并推测是由一个单一的祖先基因的串联重复。2编码的蛋白质现在执行不同的功能，但仍保留足够的同源性，允许与膜结合的P蛋白上的相同位点的相互作用。2种蛋白质之间氨基酸差异的分布;功能性嵌合蛋白质的性质，由缺失突变体产生，其中argT基因的第一半融合到hisJ基因的第二半;不能与P相互作用的突变J蛋白的序列变化允许氨基酸-结合位点和参与与P蛋白相互作用的位点被分配到每个结合蛋白的特定区域。
The hisJ and argT genes of Salmonella typhimurium encode 2 periplasmic binding proteins, J and LAO, which are involved in histidine and arginine transport, respectively, and which interact with a common membrane-bound component, the P protein. The complete nucleotide sequences of these 2 genes were determined. The 2 genes show extensive homology (70%) and presumably arose by tandem duplication of a single ancestral gene. The 2 encoded proteins now perform distinct functions but still retain sufficient homology to permit interaction with the same site on the membrane-bound P protein. The distribution of amino acid differences between the 2 proteins; the properties of a functional chimeric protein, produced by a deletion mutant in which the 1st half of the argT gene is fused to the 2nd half of the hisJ gene; and the sequence change in a mutant J protein unable to interact with P allowed the amino acid-binding site and the site involved in the interaction with the P protein to be assigned to specific regions of each binding protein.