Light‐induced carotenogenesis in Myxococcus xanthus: evidence that CarS acts as an anti‐repressor of CarA
Light‐induced carotenogenesis in Myxococcus xanthus: evidence that CarS acts as an anti‐repressor of CarA
复制标题
光诱导黄色粘球菌中的胡萝卜素生成：CarS 作为 CarA 抗阻遏剂的证据
DOI：
10.1046/j.1365-2958.2001.02679.x
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发表时间：
2001
影响因子：
3.6
通讯作者：
D. Hodgson
中科院分区：
文献类型：
--
作者：
D. Whitworth;D. Hodgson
在细菌黄色粘球菌（Myxococcus xanthus）中，作为crt类胡萝卜素生物合成基因表达的结果，类胡萝卜素响应于光照而产生。大多数crt基因聚集在crtEBDC操纵子中，该操纵子在黑暗中被CarA抑制。遗传数据表明，在光中，合成汽车并通过去除CarA的抑制作用来实现crtEBDC操纵子的激活。由于汽车不含已知的DNA结合基序，因此推测CarA介导的抑制的缓解是由这两种蛋白质之间的直接相互作用引起的。酵母双杂交系统的使用证明了CarA和汽车之间的直接相互作用。双杂交系统还意味着CarA和可能的汽车能够同源二聚化。在体外提供了汽车抗阻遏作用的直接证据。谷胱甘肽S-转移酶（GST）-CarA蛋白融合体显示与crtEBDC启动子内的回文操纵子序列特异性结合。阻止CarA与其操纵子结合，并通过加入纯化的汽车除去预先结合的CarA。因此，汽车是一种抗阻遏物。
In the bacterium Myxococcus xanthus, carotenoids are produced in response to illumination, as a result of expression of the crt carotenoid biosynthesis genes. The majority of crt genes are clustered in the crtEBDC operon, which is repressed in the dark by CarA. Genetic data suggest that, in the light, CarS is synthesized and achieves activation of the crtEBDC operon by removing the repressive action of CarA. As CarS contains no known DNA‐binding motif, the relief of CarA‐mediated repression was postulated to result from a direct interaction between these two proteins. Use of the yeast two‐hybrid system demonstrated direct interaction between CarA and CarS. The two‐hybrid system also implied that CarA and, possibly, CarS are capable of homodimerization. Direct evidence for CarS anti‐repressor action was provided in vitro. A glutathione S‐transferase (GST)–CarA protein fusion was shown to bind specifically to a palindromic operator sequence within the crtEBDC promoter. CarA was prevented from binding to its operator, and prebound CarA was removed by the addition of purified CarS. CarS is therefore an anti‐repressor.
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DOI：
10.1073/pnas.88.21.9578
发表时间：
1991-11-01
影响因子：
11.1
作者：
CHIEN, CT;BARTEL, PL;FIELDS, S
通讯作者：
FIELDS, S
影响因子：
5.6
作者：
Lewis, RJ;Brannigan, JA;Wilkinson, AJ
通讯作者：
Wilkinson, AJ
大肠杆菌热休克转录因子 sigma 32 的过量生产和纯化。
影响因子：
1.6
作者：
Nguyen,LH;Jensen,DB;Burgess,RR
通讯作者：
Burgess,RR
影响因子：
10.5
作者：
BAI, U;MANDICMULEC, I;SMITH, I
通讯作者：
SMITH, I