title: Conformational change in the catalytic site of the ribonuclease YoeB toxin by YefM antitoxin.
abstract: The eubacterial chromosome encodes various addiction modules that control global levels of translation through RNA degradation. Crystal structures of the Escherichia coli YefM2 (antitoxin)-YoeB (toxin) complex and the free YoeB toxin have been determined. The structure of the heterotrimeric complex reveals an asymmetric disorder-to-order recognition strategy, in which one C terminus of the YefM homodimer exclusively interacts with an atypical microbial ribonuclease (RNase) fold of YoeB. Comparison with the YefM-free YoeB structure indicates a conformational rearrangement of the RNase catalytic site of YoeB, induced by interaction with YefM. Complementary biochemical experiments demonstrate that the YoeB toxin has an in vitro RNase activity that preferentially cleaves at the 3' end of purine ribonucleotides.
authors.affiliation: Cellular Physiology Laboratory, RIKEN Discovery Research Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. kamadak@riken.jp
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kamada
authors.forename: Fumio
authors.initials: F
authors.lastname: Hanaoka
mesh_terms: D000595:Amino Acid Sequence; D001427:Bacterial Toxins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D020134:Catalytic Domain / Q000502:physiology*; D018360:Crystallography, X-Ray; D019281:Dimerization; D004789:Enzyme Activation; D048168:Escherichia coli K12 / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D012260:Ribonucleases / Q000737:chemistry* / Q000235:genetics; D016415:Sequence Alignment; D013499:Surface Properties
chemical_list: D001427:Bacterial Toxins; D029968:Escherichia coli Proteins; C484519:YefM protein, E coli; C504245:YoeB protein, E coli; D012260:Ribonucleases