| Accession | GenProp0147 |
| Name | glycine betaine biosynthesis from choline |
| Type | PATHWAY |
| Description | As a coping mechanism against osmotic stress, prokaryotic organisms accumulate osmolytes or osmoprotectants from exogenous sources, to counterbalance elevated osmolarities in the environment without affecting overall cell metabolism and structural integrity [1]. One of the most efficient osmoprotectants found in the environment is the compound glycine betaine [1]. Both gram positive and gram negative bacteria mediate osmotolerance either by direct uptake of glycine betaine from the environment, or by synthesis from exogenously supplied choline [2,3]. This property reflects the biosynthesis of the osmoprotectant glycine betaine from choline [4,5]. Biosynthesis of glycine betaine occurs via a two-step oxidative reaction requiring a terminal electron acceptor [2,3]. Choline dehydrogenase first catalyzes the conversion of exogenously supplied choline into the intermediate glycine betaine aldehyde, with subsequent oxidization by betaine aldehyde dehydrogenase into the osmoprotectant glycine betaine [2,3]. Both choline dehydrogenase and betaine aldehyde dehydrogenase are required for conversion of choline into glycine betaine [2,3]. |
| JCVI Role | Adaptations to atypical conditions |
| Parent Property | GenProp0267: osmolyte biosynthesis
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| Literature References | [ 1 ]Csonka LN, Hanson AD. Prokaryotic osmoregulation: genetics and physiology. Annu Rev Microbiol. 1991;45:569-606. PMID 1741624
[ 2 ]Andresen PA, Kaasen I, Styrvold OB, Boulnois G, Strom AR Molecular cloning, physical mapping and expression of the bet genes governing the osmoregulatory choline-glycine betaine pathway of Escherichia coli J Gen Microbiol. 1988 Jun;134 ( Pt 6):1737-46. PMID 3065456
[ 3 ]Boch J, Kempf B, Schmid R, Bremer E. Synthesis of the osmoprotectant glycine betaine in Bacillus subtilis: characterization of the gbsAB genes. J Bacteriol. 1996 Sep;178(17):5121-9. PMID 8752328
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| Web References | The Ecocyc Database: betaine biosynthesis I
KEGG: Glycine, serine and threonine metabolism
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| Gene Ontology Term | GO:0019285: glycine betaine biosynthetic process from choline (biological_process)
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