THE ALGT (ALGU) GENE OF PSEUDOMONAS-AERUGINOSA, A KEY REGULATOR INVOLVED IN ALGINATE BIOSYNTHESIS, ENCODES AN ALTERNATIVE SIGMA-FACTOR (SIGMA(E))
THE ALGT (ALGU) GENE OF PSEUDOMONAS-AERUGINOSA, A KEY REGULATOR INVOLVED IN ALGINATE BIOSYNTHESIS, ENCODES AN ALTERNATIVE SIGMA-FACTOR (SIGMA(E))
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DOI：
10.1073/pnas.92.17.7941
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发表时间：
1995-08-15
影响因子：
11.1
通讯作者：
CHAKRABARTY, AM
中科院分区：
文献类型：
--
作者：
HERSHBERGER, CD;YE, RW;CHAKRABARTY, AM
由产藻酸盐（粘液样）绿脓杆菌引起的慢性感染是囊性纤维化（CF）患者死亡的主要原因。在持续感染的过程中，海藻酸盐胶囊的产生保护了细菌，并允许它们在CF肺中持续存在。海藻酸盐合成的关键调控因子之一是algT （algU）基因，该基因编码一种假定的替代sigma因子（sigma(E)）， algT是从大肠杆菌中大量产生和纯化的。纯化蛋白的n端序列与DNA序列预测的n端序列完全匹配。纯化后的蛋白，在大肠杆菌RNA聚合酶核心酶存在下，能够启动一个algT启动子的转录。该启动子-35区域的缺失在体内和体外均可消除该活性。这些数据表明，algT基因编码一个自我调节的sigma因子。
Chronic infection by alginate-producing (mucoid) Pseudomonas aenuginosa is the leading cause of mortality among cystic fibrosis (CF) patients. During the course of sustained infection, the production of an alginate capsule protects the bacteria and allows them to persist in the CF lung. One of the key regulators of alginate synthesis is the algT (algU) gene encoding a putative alternative sigma factor (sigma(E)), AlgT was hyperproduced and purified from Escherichia coli. The N-terminal sequence of the purified protein matched perfectly with that predicted from the DNA sequence. The purified protein, in the presence of E. coli RNA polymerase core enzyme, was able to initiate transcription of an algT promoter. Deletion of the -35 region of this promoter abolished this activity in vitro as well as in vivo. These data indicate that the algT gene encodes a sigma factor that is autoregulatory.