CLONING AND CHARACTERIZATION OF PVDS, A GENE REQUIRED FOR PYOVERDINE SYNTHESIS IN PSEUDOMONAS-AERUGINOSA - PVDS IS PROBABLY AN ALTERNATIVE SIGMA-FACTOR
CLONING AND CHARACTERIZATION OF PVDS, A GENE REQUIRED FOR PYOVERDINE SYNTHESIS IN PSEUDOMONAS-AERUGINOSA - PVDS IS PROBABLY AN ALTERNATIVE SIGMA-FACTOR
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DOI：
10.1128/jb.177.10.2744-2750.1995
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发表时间：
1995-05-01
影响因子：
3.2
通讯作者：
LAMONT, IL
中科院分区：
文献类型：
--
作者：
CUNLIFFE, HE;MERRIMAN, TR;LAMONT, IL
铜绿假单胞菌的细胞当在缺铁条件下生长时分泌荧光黄绿色铁载体绿脓菌荧光素。我们在此描述了该过程所需的基因pvdS的克隆和表征。pvdS基因是从至少两个绿脓菌荧光素合成基因的启动子表达所需的，并且可以引起这些启动子在大肠杆菌中表达，在大肠杆菌中它们否则是无活性的。pvdS基因的序列分析表明，pvdS基因是RNA聚合酶σ因子亚家族的一员，该家族的功能是指导细菌合成胞外产物。我们提出，在铜绿假单胞菌的富铁细胞中，Fur与pvdS启动子结合并阻止该基因的表达;在铁饥饿的条件下，阻遏被解除并产生PvdS，重新编程细胞用于绿脓菌荧光素合成。
Cells of Pseudomonas aeruginosa secrete a fluorescent yellow-green siderophore, pyoverdine, when grown under iron deficient conditions, We describe here the cloning and characterization of a gene, pvdS, which is required for this process, The pvdS gene is required for expression from promoters of at least two pyoverdine synthesis genes and can cause expression from these promoters in Escherichia coli, where they are otherwise inactive, Sequencing of pvdS revealed that it is a member of a subfamily of RNA polymerase sigma factors which direct the synthesis of extracellular products by bacteria, The pvdS gene is expressed only in iron-starved bacteria, and in E. coli cells at least, expression is regulated by the Fur repressor protein, We propose that in iron-rich cells of P. aeruginosa, Fur binds to the pvdS promoter and prevents expression of the gene; under conditions of iron starvation, repression is relieved and PvdS is made, reprogramming the cells for pyoverdine synthesis.