Isolation and characterization of 3-N-trimethylamino-1-propanol-degrading Rhodococcus sp. strain A2

The aerobic degradation of 3-N-trimethylamino-1-propanol (homocholine) as a sole source of carbon and nitrogen has been found for a Rhodococcus sp. bacterium isolated from soil. The isolate was identified as Rhodococcus sp. strain A2 based on its phenotypic features, physiological and biochemical characteristics, and results of phylogenetic analysis. The washed cells of strain A2 completely degraded homocholine within 6 h, with concomitant formation of several metabolites. Analysis of the metabolites using capillary electrophoresis, fast atom bombardment-MS, and GC-MS showed that trimethylamine was the major metabolite, in addition to beta-alanine betaine (beta-AB) and trimethylaminopropionaldehyde. Therefore, the possible degradation pathway of homocholine in the isolated strain is through consequent oxidation of the alcohol group (-OH) to aldehyde (-CHO) and acid (-COOH). Thereafter, the cleavage of beta-AB C-N bonds yielded trimethylamine and alkyl chain.