Proteome analysis of extracellular proteins regulated by the las and rhl quorum sensing systems in Pseudomonas aeruginosa PAO1
Proteome analysis of extracellular proteins regulated by the las and rhl quorum sensing systems in Pseudomonas aeruginosa PAO1
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DOI：
10.1099/mic.0.25967-0
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发表时间：
2003-05-01
期刊：
影响因子：
2.8
通讯作者：
Cordwell, SJ
中科院分区：
文献类型：
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作者：
Nouwens, AS;Beatson, SA;Cordwell, SJ
在铜绿假单胞菌中，LAS和RHL群体感应(QS)系统调节几个基因的表达，以响应细胞密度的变化。其中许多基因编码表面相关或分泌的毒力因子。从野生型和铜绿假单胞菌PAO1突变株中收集LASRI、rhIRI和VFR基因中的一个或多个缺失的固定相培养上清液中的蛋白质，并进行双向凝胶电泳分析。所有突变体释放的蛋白质量都明显低于野生型。用图像分析比较每个菌株的蛋白质斑点模式，并用质谱仪鉴定可见斑点的差异。几个未知的OS调节蛋白被鉴定，包括一个氨基肽酶(PA2939)、一个内蛋白酶(PRPL)和一个独特的“假设”蛋白(PA0572)，这些蛋白在Delta/AS突变体的培养上清液中不能检测到，尽管它们在Deltarhl突变体中没有受到影响。当LASRI或rhIRI基因中的任何一个被破坏时，都无法检测到几丁质结合蛋白(CbpD)和一个与宿主因子I(HF-1)相似的假想蛋白(PA4944)。在OS突变体的培养上清液中有14种蛋白质的含量显著增加，这表明QS也可能负向调控某些基因的表达。观察到两个伙伴分泌外蛋白(PA0041和PA4625)水平的增加，这可能与CS缺陷背景下其同源转运蛋白的稳定性增加有关。已知的QS调控的胞外蛋白，包括弹性蛋白酶(LasB)、LASA蛋白酶(LASA)和碱性金属蛋白酶(APRA)也被检测到。
The las and rhl quorum sensing (QS) systems regulate the expression of several genes in response to cell density changes in Pseudomonas aeruginosa. Many of these genes encode surface-associated or secreted virulence factors. Proteins from stationary phase culture supernatants were collected from wild-type and P. aeruginosa PAO1 mutants deficient in one or more of the lasRI, rhIRI and vfr genes and analysed using two-dimensional gel electrophoresis. All mutants released significantly lower amounts of protein than the wild-type. Protein spot patterns from each strain were compared using image analysis and visible spot differences were identified using mass spectrometry. Several previously unknown OS-regulated proteins were characterized, including an aminopeptidase (PA2939), an endoproteinase (PrpL) and a unique 'hypothetical' protein (PA0572), which could not be detected in the culture supernatants of Delta/as mutants, although they were unaffected in Deltarhl mutants. Chitin-binding protein (CbpD) and a hypothetical protein (PA4944) with similarity to host factor I (HF-1) could not be detected when any of the lasRI or rhIRI genes were disrupted. Fourteen proteins were present at significantly greater levels in the culture supernatants of OS mutants, suggesting that QS may also negatively control the expression of some genes. Increased levels of two-partner secretion exoproteins (PA0041 and PA4625) were observed and may be linked to increased stability of their cognate transporters in a CS-defective background. Known QS-regulated extracellular proteins, including elastase (lasB), LasA protease (lasA) and alkaline metalloproteinase (aprA) were also detected.