Phenotypic characterization of pore mutants of the Vibrio cholerae porin OmpU.
Phenotypic characterization of pore mutants of the Vibrio cholerae porin OmpU.
复制标题
霍乱弧菌孔蛋白 OmpU 孔突变体的表型特征。
DOI：
10.1128/jb.01163-07
复制
发表时间：
2007
影响因子：
3.2
通讯作者：
Delcour,AnneH
中科院分区：
文献类型：
--
作者：
Pagel,Melissa;Simonet,Valerie;Li,Jie;Lallemand,Mathilde;Lauman,Brian;Delcour,AnneH
一般扩散的孔道形成大的β桶通道，控制革兰氏阴性细菌外膜对营养物质、一些抗生素和外部信号的渗透性。在这里，我们分析了霍乱弧菌OmpU孔蛋白基因突变的影响，这些保守残基已知会影响Escherichia coliporins OmpF和OMPC的孔特性。研究了不同的表型，包括对β-内酰胺类抗生素的敏感性，在大糖上的生长，以及对脱氧胆酸钠的敏感性和生物被膜，脱氧胆酸钠是这种肠道病原体的一种主要胆汁成分，作为外部信号参与了这种肠道病原体的多种细胞反应。总体而言，我们的结果表明，特定的残基在控制不同化合物的通过中发挥着不同的作用。在大糖或脱氧胆酸钠存在的情况下，桶壁精氨酸残基在毛孔中突出的突变会影响毛孔的大小和生长。对大头孢菌素类药物的敏感性主要受位于L3环上的同源基因D116的影响。Coli，OmpF，是这些药物的已知结合决定因素。L3环残基也影响生物被膜的诱导。结果用基于E的结构的同调模型来解释。粘菌素类药物。
General-diffusion porins form large β-barrel channels that control the permeability of the outer membrane of gram-negative bacteria to nutrients, some antibiotics, and external signals. Here, we have analyzed the effects of mutations in the OmpU porin ofVibrio choleraeat conserved residues that are known to affect pore properties in theEscherichia coliporins OmpF and OmpC. Various phenotypes were investigated, including sensitivity to β-lactam antibiotics, growth on large sugars, and sensitivity to and biofilm induction by sodium deoxycholate, a major bile component that acts as an external signal for multiple cellular responses of this intestinal pathogen. Overall, our results indicate that specific residues play different roles in controlling the passage of various compounds. Mutations of barrel wall arginine residues that protrude in the pore affect pore size and growth in the presence of large sugars or sodium deoxycholate. Sensitivity to large cephalosporins is mostly affected by D116, located on the L3 loop, whose homolog inE. coli, OmpF, is a known binding determinant for these drugs. L3 loop residues also affect biofilm induction. The results are interpreted in terms of a homology model based on the structures ofE. coliporins.