Open AccessNa + ‐independence of the stability under alkaline conditions of the membrane of an alkalophilic Bacillus
Author(s) -
Koyama Noriyuki
Publication year - 1989
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1989.tb03542.x
Subject(s) - membrane , chemistry , vesicle , alkaline phosphatase , membrane potential , cytochrome c oxidase , biophysics , biochemistry , enzyme , inorganic chemistry , biology
The stability under alkaline conditions of the membrane of the alkalophile was studied. By an alkaline treatment in the absence of Na + or Li + , the abilities of the membrane vesicles, when energized with ascorbate plus tetramethylphenylenediamine, to produce a membrane potential (negative, inside) and transmembrane pH gradient (outside > inside) were rapidly lost. The activity of cytochrome oxidase was not affected by the alkaline treatment irrespective of the presence of Na + . It is likely that the membrane structure is sensitive to an alkaline pH and maintained specifically by the presence of Na + (or Li + ) in the alkaline medium.