The riboswitch-mediated control of sulfur metabolism in bacteria

The riboswitch-mediated control of sulfur metabolism in bacteria.

Vitaly Epshtein, Alexander S Mironov, Evgeny Nudler

Department of Biochemistry, New York University Medical Center, New York, NY 10016, USA.

Proceedings of the National Academy of Sciences (impact factor: 9.68). 05/2003; 100(9):5052-6. DOI:10.1073/pnas.0531307100

Source: PubMed

ABSTRACT Many operons in Gram-positive bacteria that are involved in methionine (Met) and cysteine (Cys) biosynthesis possess an evolutionarily conserved regulatory leader sequence (S-box) that positively controls these genes in response to methionine starvation. Here, we demonstrate that a feed-back regulation mechanism utilizes S-adenosyl-methionine as an effector. S-adenosyl-methionine directly and specifically binds to the nascent S-box RNA, causing an intrinsic terminator to form and interrupt transcription prematurely. The S-box leader RNA thus expands the family of newly discovered riboswitches, i.e., natural regulatory RNA aptamers that seem to sense small molecules ranging from amino acid derivatives to vitamins.

11.03.2013, 3085 просмотров.