Physiological comparison of D-cysteine desulfhydrase of Escherichia coli with 3-chloro-D-alanine dehydrochlorinase of Pseudomonas putida CR 1-1.
D-Cysteine desulfhydrase of Escherichia coli W3110 delta trpED102/F' delta trpED102 was physiologically characterized. It was found to be located in the cytosolic fraction, as 3-chloro-D-alanine dehydrochlorinase is. D-Cysteine desulfhydrase catalyzed not only the alpha, beta-elimination reaction of O-acetyl-D-serine to form pyruvate, acetic acid and ammonia, but also the beta-replacement reaction of O-acetyl-D-serine with sulfide to form D-cysteine. However, these reactions appeared not to proceed in vivo. No other activity of D-cysteine synthesis from O-acetyl-D-serine and sulfide was detected in a crude cell extract of E. coli which was immunotitrated with antibodies raised against the purified D-cysteine desulfhydrase. Although D-cysteine desulfhydrase catalyzes the degradation (alpha, beta-elimination reaction) of 3-chloro-D-alanine, which is an effective antibacterial agent, E. coli W3110 delta trpED102/F' delta trpED102 did not show resistance against 3-chloro-D-alanine. Therefore, D-cysteine desulfhydrase does not contribute to 3-chloro-D-alanine detoxification in vivo.
D003542:Cystathionine gamma-Lyase / Q000378:metabolism*; D003545:Cysteine / Q000096:biosynthesis; D003600:Cytosol / Q000201:enzymology; D004926:Escherichia coli / Q000201:enzymology* / Q000648:ultrastructure; D008190:Lyases / Q000378:metabolism*; D011549:Pseudomonas / Q000201:enzymology*; D012694:Serine / Q000031:analogs & derivatives / Q000378:metabolism; D015091:beta-Alanine / Q000031:analogs & derivatives / Q000378:metabolism
D015091:beta-Alanine; C006977:3-chloroalanine; D012694:Serine; D008190:Lyases; D003542:Cystathionine gamma-Lyase; C031729:3-chloro-D-alanine dehydrochlorinase; C043943:O-acetylserine; D003545:Cysteine