Transcription termination control of the S box system: Direct measurement of S-adenosylmethionine by the leader RNA

摘要: Modulation of the structure a leader RNA to control formation an intrinsic termination signal is common mechanism for regulation gene expression in bacteria. Expression S box genes Gram-positive organisms induced response limitation methionine. We previously postulated that methionine availability monitored by binding regulatory factor and suggested or S-adenosylmethionine (SAM) could serve as metabolic signal. In this study, we show efficient region bacterial polymerase depends on SAM but not other related compounds. also directly binds induces conformational change RNA. Both SAM-directed transcription were blocked mutations cause constitutive vivo. Overproduction synthetase Bacillus subtilis resulted delay induction starvation, consistent with hypothesis molecular effector These results indicate concentration sensed nascent transcript absence trans-acting factor.