title: The PaaX repressor, a link between penicillin G acylase and the phenylacetyl-coenzyme A catabolon of Escherichia coli W.
abstract: The pac gene, encoding the penicillin G acylase from Escherichia coli W, is regulated by the PaaX repressor of the phenylacetate catabolic pathway. pac expression depends on the synthesis of phenylacetyl-coenzyme A. PaaX and the cyclic AMP receptor protein (CRP) bind in vitro to the Ppac promoter region. A palindromic sequence proposed as the PaaX operator is located upstream of the -35 box overlapping a CRP binding site, an unusual position that suggests a novel regulatory mechanism.
authors.affiliation: Department of Molecular Microbiology, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Galán
authors.forename: José L
authors.initials: JL
authors.lastname: García
authors.forename: María A
authors.initials: MA
authors.lastname: Prieto
mesh_terms: D000105:Acetyl Coenzyme A / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D010399:Penicillin Amidase / Q000235:genetics / Q000378:metabolism*; D010648:Phenylacetates / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D010648:Phenylacetates; D012097:Repressor Proteins; D000105:Acetyl Coenzyme A; C037816:phenylacetyl-coenzyme A; D010399:Penicillin Amidase