Br. Belitsky et Al. Sonenshein, ROLE AND REGULATION OF BACILLUS-SUBTILIS GLUTAMATE-DEHYDROGENASE GENES, Journal of bacteriology (Print), 180(23), 1998, pp. 6298-6305
The complete Bacillus subtilis genome contains two genes with the pote
ntial to encode glutamate dehydrogenase (GlutDH) enzymes. Mutations in
these genes were constructed and characterized. The rocG gene proved
to encode a major GlutDH whose synthesis was induced in media containi
ng arginine or ornithine or, to a lesser degree, proline and was repre
ssed by glucose. A rorG null mutant was impaired in utilization of arg
inine, ornithine, and proline as nitrogen or carbon sources. Thc gudB
gene was expressed under all growth conditions tested but codes for a
GlutDN that seemed to be intrinsically inactive. Spontaneous mutations
in gudB that removed a 9-bp direct repeat within the wild-type gudB s
equence activated the GudB protein and allowed more-efficient utilizat
ion of amino acids of the glutamate family.