title: DNA sequence and analysis of the bet genes encoding the osmoregulatory choline-glycine betaine pathway of Escherichia coli.
abstract: The sequence was determined of 6493 nucleotides encompassing the bet genes of Escherichia coli which encode the osmoregulatory choline-glycine betaine pathway. Four open reading frames were identified: betA encoding choline dehydrogenase, a flavoprotein of 61.9kDa; betB encoding betaine aldehyde dehydrogenase (52.8kDa); betT encoding a proton-motive-force-driven, high-affinity transport system for choline (75.8kDa); and betl, capable of encoding a protein of 21.8kDa, implicated as a repressor involved in choline regulation of the bet genes. Identification of the genes was supported by subcloning, physical mapping of lambda placMu53 insertions, amino acid sequence similarity, or N-terminal amino acid sequencing. The bet genes are tightly spaced, with betT located upstream of, and transcribed divergently to, the tandemly linked betIBA genes.
authors.affiliation: Norwegian College of Fishery Sciences, University of Tromsø.
authors.forename: T
authors.initials: T
authors.lastname: Lamark
authors.forename: I
authors.initials: I
authors.lastname: Kaasen
authors.forename: M W
authors.initials: MW
authors.lastname: Eshoo
authors.forename: P
authors.initials: P
authors.lastname: Falkenberg
authors.forename: J
authors.initials: J
authors.lastname: McDougall
authors.forename: A R
authors.initials: AR
authors.lastname: Strøm
mesh_terms: D000429:Alcohol Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D000445:Aldehyde Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D050728:Betaine-Aldehyde Dehydrogenase; D001692:Biological Transport; D002794:Choline / Q000378:metabolism*; D050545:Choline Dehydrogenase; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005998:Glycine / Q000378:metabolism*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D009997:Osmotic Pressure; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D000429:Alcohol Oxidoreductases; D050545:Choline Dehydrogenase; D000445:Aldehyde Oxidoreductases; D050728:Betaine-Aldehyde Dehydrogenase; D002794:Choline; D005998:Glycine