Open AccessCloning and characterization of the l ‐cysteine desulfhydrase gene of Fusobacterium nucleatum
Author(s) -
Fukamachi Haruka,
Nakano Yoshio,
Yoshimura Mamiko,
Koga Toshihiko
Publication year - 2002
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2002.tb11373.x
Subject(s) - fusobacterium nucleatum , cysteine , biochemistry , escherichia coli , chemistry , cloning (programming) , gene , microbiology and biotechnology , enzyme , molecular cloning , hydrogen sulfide , biology , bacteria , gene expression , genetics , sulfur , porphyromonas gingivalis , organic chemistry , computer science , programming language
Hydrogen sulfide and methyl mercaptan are the two major compounds associated with oral malodor. These compounds are highly toxic, and are thought to play an important role in periodontal disease. Fusobacterium nucleatum , an oral bacterium, produces large amounts of hydrogen sulfide from l ‐cysteine by the enzymatic action of l ‐cysteine desulfhydrase. We cloned and sequenced the cdl gene encoding l ‐cysteine desulfhydrase from F. nucleatum ATCC 10953, and revealed that the structural cdl gene consists of 921 bp and encodes a 33.4‐kDa protein. The cloned gene was inserted into an expression vector, pDEST17, and expressed in Escherichia coli as a fused protein. The purified enzyme was tested for substrate specificity using various SH‐containing compounds. Only l ‐cysteine served as a substrate for l ‐cysteine desulfhydrase to produce hydrogen sulfide.