BIOTIN-DEPENDENT GLUTAMATE TRANSPORT IN BREVIBACTERIUM AMMONIAGENES

Abstract

Energy-dependent L-glutamate transport system in Brevibacterium ammoniagenes was studied. Its activity was repressed by biotin deficiency and was restored to its normal level by the addition of sugars or salts in high concentration. In the restored system, however, a decrease was observed in its substrate specificity, while other properties remained similar to those in biotin-sufficient one. Penicillin induced requirement for hypertonicity to activate the transport system even in biotin-sufficient state, and chloramphenicol acted to reduce the rate of the restoration of substrate specificity which occurred during biotin deficient-sufficient transition. It was concluded that biotin was bifunctional in the L-glutamate transport system in this organism.