title: Regulatory role of cAMP receptor protein over Escherichia coli fumarase genes.
abstract: Escherichia coli expresses three fumarase genes, namely, fumA, fumB, and fumC. In the present study, catabolite repression was observed in the fumA-lacZ and fumC-lacZ fusion strains, but not in the fumB-lacZ fusion strain. The Crp-binding sites in fumA and fumC were identified using an electrophoretic mobility shift assay and footprint analysis. However, the electrophoretic mobility shift assay did not detect band shifts in fumB. Fnr and ArcA serve as transcription regulators of fumarase gene expression. In relation to this, different mutants, including Δcya, Δcrp, Δfnr, and ΔarcA, were used to explore the regulatory role of Crp over fumA and fumC. The results show that Crp is an activator of fumA and fumC gene expression under various oxygen conditions and growth rates. ArcA was identified as the dominant repressor, with the major repression occurring at 0-4% oxygen. In addition, Fnr was confirmed as a repressor of fumC for the first time. This study elucidates the effects of Crp on fumarase gene expression.
authors: Department of Biological Science and Technology, National Chiao Tung University, HsinChu, 300, Taiwan.
authors: Yu-Pei
authors: YP
authors: Chen
authors: Hsiao-Hsien
authors: HH
authors: Lin
authors: Chi-Dung
authors: CD
authors: Yang
authors: Shin-Hong
authors: SH
authors: Huang
authors: Ching-Ping
authors: CP
authors: Tseng
mesh_terms: D019677:Artificial Gene Fusion; D057465:Catabolite Repression; D002373:Cyclic AMP Receptor Protein / Q000378:metabolism*; D004269:DNA, Bacterial / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D004926:Escherichia coli / Q000201:enzymology* / Q000378:metabolism / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000096:biosynthesis* / Q000378:metabolism; D005649:Fumarate Hydratase / Q000096:biosynthesis; D015964:Gene Expression Regulation, Bacterial; D017930:Genes, Reporter; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D001616:beta-Galactosidase / Q000032:analysis / Q000235:genetics
chemical_list: D002373:Cyclic AMP Receptor Protein; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C481662:crp protein, E coli; D001616:beta-Galactosidase; D005649:Fumarate Hydratase