3-Chloro-DL-alanine resistance by L-methionine-alpha-deamino-gamma-mercaptomethane-lyase activity.
The antibacterial agent 3-chloro-DL-alanine (3CA) is an inhibitor of peptidoglycan synthesis. Fusobacterium nucleatum and Porphyromonas gingivalis, the bacteria responsible for oral malodor, are shown to be resistant to 1 mM 3CA, whereas Streptococcus mutans and Escherichia coli are sensitive to this antibacterial agent at the same concentration. We isolated the 3CA resistance gene from F. nucleatum and showed that the gene encodes an L-methionine-alpha-deamino-gamma-mercaptomethane-lyase that catalyzes the alpha,gamma-elimination of L-methionine to produce methyl mercaptan. The enzyme also exhibits 3CA chloride-lyase (deaminating) activity. This antibacterial agent is expected to be useful for specific selection of malodorous oral bacteria producing high amounts of methyl mercaptan.
Department of Preventive Dentistry, Kyushu University Faculty of Dental Science, 3-1-1 Maidashi, Higashi-ku, 812-8582, Fukuoka, Japan.
Mamiko
M
Yoshimura
Yoshio
Y
Nakano
Haruka
H
Fukamachi
Toshihiko
T
Koga
D000900:Anti-Bacterial Agents / Q000378:metabolism / Q000494:pharmacology; D013437:Carbon-Sulfur Lyases / Q000235:genetics / Q000378:metabolism*; D003641:Deamination; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D016967:Fusobacterium nucleatum / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D008715:Methionine / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D016966:Porphyromonas gingivalis / Q000187:drug effects; D013045:Species Specificity; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D015091:beta-Alanine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D013438:Sulfhydryl Compounds; D015091:beta-Alanine; C006977:3-chloroalanine; D008715:Methionine; D013437:Carbon-Sulfur Lyases; C021558:L-methionine gamma-lyase