A periplasmic protein disulfide oxidoreductase is required for transformation of Haemophilus influenzae Rd.
A periplasmic protein disulfide oxidoreductase is required for transformation of Haemophilus influenzae Rd.
复制标题
转化流感嗜血杆菌 Rd 需要周质蛋白二硫键氧化还原酶。
DOI：
10.1073/pnas.89.21.10252
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发表时间：
1992
影响因子：
11.1
通讯作者：
Tomb,JF
中科院分区：
文献类型：
--
作者：
Tomb,JF
对流感嗜血杆菌JG 16菌株的DNA结合和摄取能力进行了克隆，并对野生型等位基因进行了测序。该基因通过北方分析显示在1.7-β-淀粉酶转录物上组成型表达。基因产物被鉴定为靶向周质的20.6 kDa蛋白。该蛋白含有序列Cys-Pro-His-Cys（CPHC），并且与另外两种含有周质CPHC基序的蛋白高度相似：DsbA，一种大肠杆菌蛋白（45%同一性，87%同源性）和TcpG，一种霍乱弧菌蛋白（32%同一性，74%同源性）。DsbA和TcpG都促进周质蛋白中二硫键的形成，是菌毛生物发生所需的，并且像硫氧还蛋白一样，能够在体外减少胰岛素。嗜血杆菌蛋白质被证明可以补充大肠杆菌。大肠杆菌DsbA突变，命名为Por（周质氧化还原酶）。在JG 16中，内膜蛋白的能力依赖性再分配没有发生。这些研究结果表明，Por是需要正确的装配和/或折叠的一个或多个含二硫键的细胞包膜蛋白参与无论是在竞争力的发展或在DNA结合和摄取机器。
The mutated gene in JG16, a Haemophilus influenzae strain deficient in competence-induced DNA binding and uptake, was cloned and the wild-type allele was sequenced. The gene was shown by Northern analysis to be constitutively expressed on a 1.7-kilobase transcript. The gene product was identified as a 20.6-kDa protein targeted to the periplasm. The protein contains the sequence Cys-Pro-His-Cys (CPHC) and is highly similar to two other periplasmic CPHC motif-containing proteins: DsbA, an Escherichia coli protein (45% identity, 87% homology) and TcpG, a Vibrio cholerae protein (32% identity, 74% homology). Both DsbA and TcpG promote disulfide bond formation in periplasmic proteins, are required for pilus biogenesis, and, like thioredoxin, are capable of reducing insulin in vitro. The Haemophilus protein was shown to complement an E. coli mutation in DsbA and was named Por (periplasmic oxidoreductase). In JG16 the competence-dependent redistribution of inner membrane proteins did not occur. These findings suggest that Por is required for the correct assembly and/or folding of one or more disulfide-containing cell envelope protein involved either in competence development or in the DNA-binding and -uptake machinery.