title: A protein antibiotic in the phage Qbeta virion: diversity in lysis targets.
abstract: A(2), a capsid protein of RNA phage Qbeta, is also responsible for host lysis. A(2) blocked synthesis of murein precursors in vivo by inhibiting MurA, the catalyst of the committed step of murein biosynthesis. An A(2)-resistance mutation mapped to an exposed surface near the substrate-binding cleft of MurA. Moreover, purified Qbeta virions inhibited wild-type MurA, but not the mutant MurA, in vitro. Thus, the two small phages characterized for their lysis strategy, Qbeta and the small DNA phage phiX174, effect host lysis by targeting different enzymes in the multistep, universally conserved pathway of cell wall biosynthesis.
authors: Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX 77843-2128, USA..
authors: T G
authors: TG
authors: Bernhardt
authors: I N
authors: IN
authors: Wang
authors: D K
authors: DK
authors: Struck
authors: R
authors: R
authors: Young
mesh_terms: D019883:Alkyl and Aryl Transferases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017908:Allolevivirus / Q000235:genetics / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000378:metabolism* / Q000494:pharmacology; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D001433:Bacteriolysis; D010584:Bacteriophage phi X 174 / Q000378:metabolism / Q000502:physiology; D001665:Binding Sites; D002213:Capsid / Q000378:metabolism* / Q000494:pharmacology; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000821:virology*; D009154:Mutation; D010457:Peptidoglycan / Q000096:biosynthesis*; D014166:Transferases; D017855:Transferases (Other Substituted Phosphate Groups); D014537:Uridine Diphosphate N-Acetylglucosamine / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D010457:Peptidoglycan; D014537:Uridine Diphosphate N-Acetylglucosamine; D014166:Transferases; D019883:Alkyl and Aryl Transferases; C022566:UDP-N-acetylglucosamine 1-carboxyvinyltransferase; D017855:Transferases (Other Substituted Phosphate Groups); C079803:mraY protein, Bacteria