Open AccessBacterial uptake of octyl ethanolamine increases with pH
Author(s) -
Sandin Michael,
Allenmark Stig,
Edebo Lars
Publication year - 1992
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.1574-6968.1992.tb05200.x
Subject(s) - ethanolamine , chemistry , membrane , cytoplasm , protonation , penetration (warfare) , diffusion , vesicle , nuclear chemistry , chromatography , biophysics , biochemistry , organic chemistry , biology , ion , physics , operations research , engineering , thermodynamics
The uptake of octyl ethanolamine (C 8 EA) by Pseudomonas pseudoalcaligenes was determined at pH 7.1–10.0. At pH 9.1 the total uptake was nearly three times higher, and at pH 10.0 four times higher than at pH 7.1. Also the initial rate of uptake was lowest at pH 7.1. At pH 7.1 five to ten times higher concentrations of C 8 EA were needed than at pH 9.1 to achieve the same degree of leakage of cytoplasmic constituents. The results support the hypothesis that penetration of the bacterial cytoplasmic membrane by C 8 EA in its uncharged form is favoured. This takes place particularly with high pH in the suspending medium. In the cytoplasm, the pH is lower, and C 8 EA becomes more protonated. This will prevent back diffusion, promote accumulation and enhance membrane interaction and toxicity at high pH.