title: Regulation by two CatR proteins that differ in binding affinity to catB promoters expressing two cat gene clusters.
abstract: We isolated the two LysR-type regulatory proteins CatR1 and CatR2, which regulate the expression of cat1 and cat2 gene clusters, respectively, required for catechol degradation in the bacterium Frateuria sp. ANA-18. In a gel mobility shift assay using CatR1 and the DNA fragment containing the catB1 promoter region, the formation of two complexes, complex 1-1 (C1-1) and complex 1-2 (C1-2), was observed in the presence of cis,cis-muconate. On the other hand, CatR2 and the DNA fragment containing the catB2 promoter region formed only complex 2-2 (C2-2) at a lower concentration of cis,cis-muconate than that at which C1-1 and C1-2 were formed. As the concentration of cis,cis-muconate decreased, the production of the muconate cycloisomerase isozyme MC II encoded by catB2 decreased as well as that of MC I encoded by catB1. However, the amount of MC II synthesized was larger than that of MC I at low concentrations. On the basis of these results, we concluded that the catB2 promoter was activated at low concentrations of cis,cis-muconate.
authors.affiliation: Division of Bioscience, The Graduate School of Science and Technology, Kobe University, Rokko, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Takashima
authors.forename: S
authors.initials: S
authors.lastname: Murakami
authors.forename: S
authors.initials: S
authors.lastname: Takenaka
authors.forename: K
authors.initials: K
authors.lastname: Aoki
mesh_terms: D001426:Bacterial Proteins; D001483:Base Sequence; D050548:Catechol 1,2-Dioxygenase; D002396:Catechols / Q000378:metabolism; D002846:Chromatography, Affinity; D018983:DNA Footprinting; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D049308:Dioxygenases; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D016946:Gram-Negative Aerobic Rods and Cocci / Q000201:enzymology / Q000235:genetics*; D019753:Intramolecular Lyases / Q000096:biosynthesis; D007527:Isoenzymes; D008969:Molecular Sequence Data; D010105:Oxygenases / Q000096:biosynthesis / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000502:physiology*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D002396:Catechols; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D007527:Isoenzymes; D012097:Repressor Proteins; D014157:Transcription Factors; C086843:CatR protein, bacteria; D010105:Oxygenases; D049308:Dioxygenases; D050548:Catechol 1,2-Dioxygenase; D019753:Intramolecular Lyases; C021811:muconate cycloisomerase; C034221:catechol