title: Spontaneous mutations affecting transcriptional regulation by protocatechuate in Acinetobacter.
abstract: Positive selection yields Acinetobacter strains with a spontaneous mutation blocking catabolism of protocatechuate. For this study, the growth temperature during selection was lowered to 22 degrees C: growth at 37 degrees C was found to mask the role of the protocatechuate-responsive transcriptional regulator PcaU. The resulting mutants included those with amino acid substitutions useful for understanding PcaU structure and function, a 20-bp deletion whose repeated isolation suggested genetic instability of DNA in the putative PcaU operator, and a large deletion whose phenotype revealed that the supraoperonic cluster of genes for the protocatechuate branch of the beta-ketoadipate pathway extends to genes for the utilization of C(6)-C(10) straight-chain dicarboxylic acids including adipate.
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, Yale University, P.O. Box 208103, New Haven, CT 06520-8103, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: D'Argenio
authors.forename: A
authors.initials: A
authors.lastname: Segura
authors.forename: P V
authors.initials: PV
authors.lastname: Bünz
authors.forename: L N
authors.initials: LN
authors.lastname: Ornston
mesh_terms: D000150:Acinetobacter / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D019943:Amino Acid Substitution; D001426:Bacterial Proteins; D021901:DNA, Intergenic; D003998:Dicarboxylic Acids / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005809:Genes, Regulator; D062385:Hydroxybenzoates / Q000378:metabolism*; D009154:Mutation; D010641:Phenotype; D017384:Sequence Deletion; D013696:Temperature; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D021901:DNA, Intergenic; D003998:Dicarboxylic Acids; D062385:Hydroxybenzoates; C111304:PcaU protein, Acinetobacter; D015534:Trans-Activators; C009091:protocatechuic acid