title: The metabolism of caffeine by a Pseudomonas putida strain.
abstract: 1) A bacterium capable of growing aerobically with caffeine (1,3,7-trimethylxanthine) as sole source of carbon and nitrogen was isolated from soil. The morphological and physiological characteristics of the bacterium were examined. The organism was identified as a strain of Pseudomonas putida and is referred to as Pseudomonas putida C1. 15 additional caffeine-degrading bacteria were isolated, and all of them were also identified as Pseudomonas putida strains. The properties of the isolates are discussed in comparison with 6 Pseudomonas putida strains of the American Type Culture Collection. 2) The degradation of caffeine by Pseudomonas putida C1 was investigated; the following 14 metabolites were identified: 3,7-dimethylxanthine (theobromine), 1,7-dimethylxanthine, 7-methylxanthine, xanthine, 3,7-dimethyluric acid, 1,7-dimethyluric acid, 7-methyluric acid, uric acid, allantoin, allantoic acid, ureidoglycolic acid, glyoxylic acid, urea, and formaldehyde. Formaldehyde has been demonstrated to be the product of oxidative N-demethylation mediated by an inducible demethylase. A pathway of caffeine degradation is proposed.
mesh_terms: D002110:Caffeine / Q000378:metabolism*; D005557:Formaldehyde / Q000378:metabolism; D006038:Glyoxylates / Q000378:metabolism; D008854:Microscopy, Electron; D009154:Mutation; D011549:Pseudomonas / Q000378:metabolism* / Q000648:ultrastructure; D013045:Species Specificity; D013329:Structure-Activity Relationship
chemical_list: D006038:Glyoxylates; D005557:Formaldehyde; D002110:Caffeine