Homocysteine biosynthesis pathways of Streptococcus anginosus.
A gene (cgs) encoding cystathionine gamma-synthase was cloned from Streptococcus anginosus, and its protein was purified and characterized. The cgs gene and the immediately downstream lcd gene were shown to be cotranscribed as an operon. High-performance liquid chromatography analyses showed that the S. anginosus Cgs not only has cystathionine gamma-synthase activity, but also expresses O-acetylhomoserine sulfhydrylase activity. These results suggest that S. anginosus has the capacity to utilize both the transsulfuration and direct sulfhydrylation pathways for homocysteine biosynthesis.
Department of Preventive Dentistry, Kyushu University Faculty of Dental Science, Fukuoka, Japan.
Yasuo
Y
Yoshida
Masahiro
M
Negishi
Yoshio
Y
Nakano
D000595:Amino Acid Sequence; D019757:Carbon-Oxygen Lyases; D002851:Chromatography, High Pressure Liquid; D015964:Gene Expression Regulation, Bacterial; D006710:Homocysteine / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D009876:Operon; D017386:Sequence Homology, Amino Acid; D034366:Streptococcus anginosus / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism*
D006710:Homocysteine; D013455:Sulfur; C022696:O-succinylhomoserine (thiol)-lyase; D019757:Carbon-Oxygen Lyases