title: The Bacillus subtilis ydcDE operon encodes an endoribonuclease of the MazF/PemK family and its inhibitor.
abstract: Operons encoding stable toxins and their labile antidote are widespread in prokaryotes and play important roles in plasmid partitioning and cellular responses to stress. One such family of toxins MazF/ChpAK/PemK encodes an endoribonuclease that inactivates cellular mRNAs by cleaving them at specific, but frequently occurring sites. Here we show that the Bacillus subtilis ydcE gene encodes a member of this family of RNases, which we have called EndoA. Overexpression of EndoA is toxic for bacterial cell growth and this toxicity is reversed by coexpression of the gene immediately upstream, ydcD. Furthermore, YdcD inhibits EndoA activity directly in vitro. EndoA has similar cleavage specificity to MazF and PemK and yields cleavage products with 3'-phosphate and 5'-hydroxyl groups, typical of EDTA-resistant degradative RNases. This is the first example of an antitoxin-toxin system in B. subtilis.
authors.affiliation: CNRS UPR 9073 (affiliated with Université de Paris 7 - Denis Diderot), Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005 Paris, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Pellegrini
authors.forename: Nathalie
authors.initials: N
authors.lastname: Mathy
authors.forename: Arhonda
authors.initials: A
authors.lastname: Gogos
authors.forename: Lawrence
authors.initials: L
authors.lastname: Shapiro
authors.forename: Ciarán
authors.initials: C
authors.lastname: Condon
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology; D001427:Bacterial Toxins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D004722:Endoribonucleases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008958:Models, Molecular; D009876:Operon; D012333:RNA, Messenger / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D012333:RNA, Messenger; D004722:Endoribonucleases