title: The riboswitch-mediated control of sulfur metabolism in bacteria.
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.
authors.affiliation: Department of Biochemistry, New York University Medical Center, New York, NY 10016, USA.
authors.forename: Vitaly
authors.initials: V
authors.lastname: Epshtein
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Mironov
authors.forename: Evgeny
authors.initials: E
authors.lastname: Nudler
mesh_terms: D001483:Base Sequence; D006094:Gram-Positive Bacteria / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009876:Operon; D012329:RNA, Bacterial / Q000378:metabolism; D013455:Sulfur / Q000378:metabolism*; D013728:Terminator Regions, Genetic; D014158:Transcription, Genetic
chemical_list: D012329:RNA, Bacterial; D013455:Sulfur