| Comment | Choline dehydrogenase catalyzes the conversion of exogenously supplied choline into the intermediate glycine betaine aldehyde, as part of a two-step oxidative reaction leading to the formation of osmoprotectant betaine. This enzymatic system can be found in both gram-positive and gram-negative bacteria.
As in Escherichia coli [1], Staphylococcus xylosus [2], and Sinorhizobium meliloti [3], this enzyme is found associated in a transciptionally co-induced gene cluster with betaine aldehyde dehydrogenase, the second catalytic enzyme in this reaction. Other gram-positive organisms have been shown to employ a different enzymatic system, utlizing a soluable choline oxidase or type III alcohol dehydrogenase instead of choline dehydrogenase [4].
This enzyme is a member of the GMC oxidoreductase family (PF00732 and PF05199), sharing a common evoluntionary origin and enzymatic reaction with alcohol dehydrogenase [5]. Outgrouping from this model, Caulobacter crescentus shares sequence homology with choline dehydrogenase, yet other genes participating in this enzymatic reaction have not currently been identified. |
| References | CC
CC
RN [1]
RM 3065456
RT Molecular cloning, physical mapping and expression of the bet genes governing the osmoregulatory choline-glycine betaine pathway of Escherichia coli.
RA Andresen PA, Kaasen I, Styrvold OB, Boulnois G, Strom AR.
RJ J Gen Microbiol. 1988 Jun;134 ( Pt 6):1737-46.
RN [2]
RM 10094709
RT The choline-converting pathway in Staphylococcus xylosus C2A: genetic and physiological characterization.
RA Rosenstein R, Futter-Bryniok D, Gotz F.
RJ J Bacteriol. 1999 Apr;181(7):2273-8.
RN [3]
RM 9141699
RT Molecular characterization of the bet genes encoding glycine betaine synthesis in Sinorhizobium meliloti 102F34.
RA Pocard JA, Vincent N, Boncompagni E, Smith LT, Poggi MC, Le Rudulier D.
RT Microbiology. 1997 Apr;143 ( Pt 4):1369-79.
RN [4]
RM 8752328
RT Synthesis of the osmoprotectant glycine betaine in Bacillus subtilis: characterization of the gbsAB genes.
RA Boch J, Kempf B, Schmid R, Bremer E.
RJ J Bacteriol. 1996 Sep;178(17):5121-9.
RN [5]
RM 1453953
RT DNA sequence determination and functional characterization of the OCT-plasmid-encoded alkJKL genes of Pseudomonas oleovorans.
RA van Beilen JB, Eggink G, Enequist H, Bos R, Witholt B.
RJ Mol Microbiol. 1992 Nov;6(21):3121-36.
DR PFAM; PF00732; GMC_oxred_N: GMC oxidoreductase
DR PFAM; PF05199; GMC_oxred_C: GMC oxidoreductase
DR EXPERIMENTAL; SP|P17444; Escherichia coli; Molecular cloning, physical mapping and expression of the bet genes governing the osmoregulatory choline-glycine betaine pathway of Escherichia coli.
DR EXPERIMENTAL; GP|4574121; Staphylococcus xylosus; The choline-converting pathway in Staphylococcus xylosus C2A: genetic and physiological characterization.
DR EXPERIMENTAL; SP|P54223; Sinorhizobium meliloti; Molecular characterization of the bet genes encoding glycine betaine synthesis in Sinorhizobium meliloti 102F34.
DR OUTGROUP; SP|Q00593; Pseudomonas oleovorans; Alcohol dehydrogenase
DR HAMAP; MF_00750; 84 of 85 |
