N-carbamoyl-L-cysteine as an intermediate in the bioconversion from D,L-2-amino-Delta(2)-thiazoline-4-carboxylic acid to L-cysteine by Pseudomonas sp. ON-4a

We investigated the conversion of D,L-2-amino-Delta(2)-thiazoline-4-carboxy lic acid (D,L-ATC) to L-cysteine with Pseudomonas sp. ON-4a, an ATC-assimil ating bacterium. Cysteine and N-carbamoylcysteine (NCC), but not S-carbamoy lcysteine (SCC), were produced from D,L-ATC by a cell-free extract from the strain. These products were isolated from the reaction mixture and then id entified as the L-form. Similar results were obtained with P. putida AJ3865 and unidentified strain TG-3, an ATC-assimilating bacteria. It became clea r that L-NCC is an intermediate in the conversion of D,L-ATC to L-cysteine in these Pseudomonas strains. Furthermore, it was suggested that these bact eria have L-ATC hydrolase and L-NCC amidohydrolase.