Production of trimethylamine from structurally related trimethylammonium compounds by resting cell suspensions of γ-butyrobetaine- and D,l-carnitine-grown Acinetobacter calcoaceticus and Pseudomonas putida

The degradation of trimethylammonium compounds that are structurally related to γ-butyrobetaine and D,l-carnitine has been examined with variously grown resting cell suspensions of Acinetobacter calcoaceticus and Pseudomonas putida. Ac. calcoaceticus grown on either γ-butyrobetaine effectively degraded D,l-3-fluoro-4-N-trimethylaminobutyric, 4-N-trimethylaminocrotonic and 5-N-trimethylaminopentanoic acids with stoichiometric formation of triylaminopentanoic acids with stoichiometric formation of trimethylamine. None of these betaine analogs was metabolized by Ps. putida grown on D,l-carnitine as sole source of carbon. Only D,l-carnitine-grown Ac. calcoaceticus showed a slow but significant utilization of D,l-3-chloro-4-N-trimethylaminobutyric acid with equivalent formation of trimethylamine. Neither Ac. calcoaceticus nor Ps. putida, grown on either γ-butyrobetaine or D,l-carnitine as sole source of carbon degraded any of the following quaternary ammonium compounds: glycinebetaine, N-trimethylethanolamine-O-phosphate, N-trimethylethanolamine-O-sulfate, 3-N-trimethylaminopropanol, 3-N-trimethylaminopropionitrile, 3-N-trimethylaminopropionic acid, 3-N-trimethylaminopropane sulfonic acid and 6-N-trimethylaminohexanoic acid. Cleavage of the C-N bond of 4-N-trimethylaminocrotonic acid, and lack of stereochemical specificity with respect to the configuration at C-3 for the other betaines undergoing a similar degradation with formation of trimethylamine, are inconsistent with a mechanism involving a simple Hofmann-type of elimination reaction.