Bioenergetics and the Role of Soluble Cytochromes c for Alkaline Adaptation in Gram-Negative Alkaliphilic Pseudomonas
نویسندگان
چکیده
Very few studies have been conducted on alkaline adaptation of Gram-negative alkaliphiles. The reversed difference of H(+) concentration across the membrane will make energy production considerably difficult for Gram-negative as well as Gram-positive bacteria. Cells of the alkaliphilic Gram-negative bacterium Pseudomonas alcaliphila AL15-21(T) grown at pH 10 under low-aeration intensity have a soluble cytochrome c content that is 3.6-fold higher than that of the cells grown at pH 7 under high-aeration intensity. Cytochrome c-552 content was higher (64% in all soluble cytochromes c) than those of cytochrome c-554 and cytochrome c-551. In the cytochrome c-552-dificient mutant grown at pH 10 under low-aeration intensity showed a marked decrease in μ max [h(-1)] (40%) and maximum cell turbidity (25%) relative to those of the wild type. Considering the high electron-retaining abilities of the three soluble cytochromes c, the deteriorations in the growth of the cytochrome c-552-deficient mutant could be caused by the soluble cytochromes c acting as electron storages in the periplasmic space of the bacterium. These electron-retaining cytochromes c may play a role as electron and H(+) condenser, which facilitate terminal oxidation at high pH under air-limited conditions, which is difficult to respire owing to less oxygen and less H(+).
منابع مشابه
Cytochrome c-552 from gram-negative alkaliphilic Pseudomonas alcaliphila AL15-21T alters the redox properties at high pH.
A soluble class I cytochrome c of an alkaliphile was purified and characterized, and its primary structure was determined. This is the first example of a soluble class I cytochrome c in alkaliphiles. Cells the alkaliphilic gram-negative bacterium Pseudomonas alcaliphila AL15-21(T) grown at pH 10 had a soluble cytochrome c content that was more than twofold that of strain AL15-21(T) cells grown ...
متن کاملRole of PA3574 (nalD) gene in development of ciprofloxacin resistance in Pseudomonas aeruginosa isolates
Background & Aims: Pseudomonas aeruginosa is a gram-negative opportunistic pathogen and one of the mortality causes of nosocomial infections. One of the drug resistance mechanisms in P.aeruginosa is mutation in negative regulator genes of mexAB-oprM efflux pump system such as nalD. The aim of this study was to investigate the role of nalD mutations in P. aeruginosa isolates of Guilan province i...
متن کاملEvaluation of the Phenotypic and Genotypic Effects of Satureja Khuzestanica Essence and Copper Nanocomplex on the Expression of Alkaline Protease Gene in Pseudomonas Aeruginosa by RT-PCR Method
Background & aim: Pseudomonas aeruginosa is a gram-negative bacillus and an opportunistic pathogen that causes high mortality in immunocompromised patients. The main antimicrobial activity of Satureja khuzestanica essence is due to carvacrol phenolic components. Nanomaterials can be a good choice because of low toxicity to fight pathogenic microbes. The aim of this study was to evaluate the e...
متن کاملGRAM NEGATIVE BACILLI IN BURNS
In a period of nine months, 225 strains of Gram-negative bacilli isolated from burns were identified by a variety of tests in two burn centers in Tehran. The most common species were Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Enterobacter agglomerans, Enterobacter cloacae and Klebsiella pneumoniae. Many strains of acinetobacter spp, providencia spp, proteus spp, ser...
متن کاملMembrane-bound respiratory chain of Pseudomonas aeruginosa grown aerobically.
The electron transport chain of the gram-negative bacterium Pseudomonas aeruginosa, grown aerobically, contained a number of primary dehydrogenases and respiratory components (soluble flavin, bound flavin, coenzyme Q9, heme b, heme c, and cytochrome o) in membrane particles of the organism. Cytochrome o, about 50% of the b-type cytochrome, seemed to function as a terminal oxidase in the respira...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 2015 شماره
صفحات -
تاریخ انتشار 2015