title: Antitermination of amidase expression in Pseudomonas aeruginosa is controlled by a novel cytoplasmic amide-binding protein.
abstract: Amide-inducible expression of the aliphatic amidase system of Pseudomonas aeruginosa can be reconstituted in Escherichia coli with only the amidase structural gene amiE, the negative regulator amiC and the positive regulator amiR, a transcription antitermination factor. Complementation experiments in E. coli suggest that negative control of amidase expression by AmiC is mediated by a protein-protein interaction with AmiR. Purified AmiC binds acetamide with a KD of 3.7 microM in equilibrium dialysis studies, and therefore AmiC appears to be the sensory partner of the AmiC/AmiR pair of regulatory proteins, responding to the presence of amides. Sequence analysis techniques suggest that AmiC is a member of the structural family of periplasmic binding proteins, but has a distinct and novel cytoplasmic role.
authors.affiliation: Biomolecular Structure Group, University College London, UK.
authors.forename: S A
authors.initials: SA
authors.lastname: Wilson
authors.forename: S J
authors.initials: SJ
authors.lastname: Wachira
authors.forename: R E
authors.initials: RE
authors.lastname: Drew
authors.forename: D
authors.initials: D
authors.lastname: Jones
authors.forename: L H
authors.initials: LH
authors.lastname: Pearl
mesh_terms: D000581:Amidohydrolases / Q000096:biosynthesis* / Q000235:genetics; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000378:metabolism*; D016384:Consensus Sequence; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D005798:Genes, Bacterial; D005809:Genes, Regulator; D005816:Genetic Complementation Test; D007700:Kinetics; D008969:Molecular Sequence Data; D009876:Operon; D033902:Periplasmic Binding Proteins; D017433:Protein Structure, Secondary; D011550:Pseudomonas aeruginosa / Q000201:enzymology* / Q000378:metabolism; D012097:Repressor Proteins / Q000378:metabolism*; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D033902:Periplasmic Binding Proteins; D012097:Repressor Proteins; C070135:AmiC protein, Pseudomonas aeruginosa; D000581:Amidohydrolases; C019665:amidase