Open AccessRole of glutamine as a direct co‐repressor of glutamine synthetase in Rhodobacter capsulatus E1F1
Author(s) -
Romero Francisco,
Quintero Antonio,
Roldán JoséManuel
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.tb03028.x
Subject(s) - glutamine synthetase , glutamine , rhodobacter , biochemistry , enzyme , repressor , methionine , amino acid , biology , chemistry , gene expression , mutant , gene
High performance liquid chromatography (HPLC) has been used to determine the internal levels of amino acids in Rhodobacter capsulatus E1F1 cells, subjected to different treatments and nutritional conditions. Glutamine synthetase activity and enzyme concentration correlated negatively with the level of glutamine, suggesting that glutamine per se acts as a co‐repressor in the enzyme synthesis. Moreover, addition of the specific inhibitor l ‐methionine‐ d,l ‐sulfoximine, that produced an increase in enzyme concentration, specifically promoted a depletion of intracellular glutamine.