Icho T
Department of Biochemistry, College of Agricultural and Life Science, University of Wisconsin, Madison 53706.
J Bacteriol. 1988 Nov;170(11):5117-24. doi: 10.1128/jb.170.11.5117-5124.1988.
The phosphatidyl glycerophosphate B phosphatase of Escherichia coli has a multiple substrate specificity and a peculiar dual subcellular localization in the envelope. Its phosphatidyl glycerophosphate phosphatase activity is higher in the cytoplasmic membrane, while phosphatidic acid and lysophosphatidic acid phosphatase activities are higher in the outer membrane. The DNA sequencing of the pgpB gene revealed a protein of 251 amino acids which had at least five hydrophobic membrane-spanning regions. About 37 hydrophilic residues in the middle of the sequence had considerable homology with the C-terminal conserved region of the ras family genes in eucaryotes. A protein of 28,000 daltons was expressed from the pgpB gene under a tac promoter in a runaway replication plasmid. This overproduced protein also revealed the dual subcellular localization.
大肠杆菌的磷脂酰甘油磷酸B磷酸酶具有多种底物特异性，并且在包膜中具有独特的双亚细胞定位。其磷脂酰甘油磷酸酶活性在细胞质膜中较高，而磷脂酸和溶血磷脂酸磷酸酶活性在外膜中较高。pgpB基因的DNA测序揭示了一个由251个氨基酸组成的蛋白质，该蛋白质至少有五个疏水跨膜区域。序列中间约37个亲水性残基与真核生物中ras家族基因的C端保守区域具有相当的同源性。在失控复制质粒中，在tac启动子下从pgpB基因表达了一种28,000道尔顿的蛋白质。这种过量产生的蛋白质也显示出双亚细胞定位。
