Characterization of the third chitinase Chi18C of Clostridium paraputrificum M-21.
A novel chitinase gene chiC of Clostridium paraputrificum M-21, a chitinolytic and hydrogen-gas-producing bacterium, was characterized along with its translated product. The chi18C gene encodes 683 amino acids (signal peptide included) with a deduced molecular weight of 74,651. Chi18C is a modular enzyme composed of a family-18 catalytic module of glycoside hydrolases, two reiterated modules of unknown function, and a family-12 carbohydrate-binding module. Recombinant Chi18C was active toward soluble and insoluble chitin preparations, and synthetic substrates such as 4-methylumbelliferyl-beta-D: -N-N'-N''-triacetylchitotriose, but not active toward 4-MU-N-acetylglucosamine or 4-MU-beta-D: -N-N'-diacetylchitobioside. Sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunological analyses suggested that the expression of chi18C was inducible with chitinous substrates and that Chi18C was secreted into the culture medium. A possible role of Chi18C in the chitinolytic system of C. paraputrificum M-21 is discussed.
Morimoto
Kenji
K
Rare Sugar Research Center, Kagawa University, 2393 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0795, Japan.
Yoshimoto
Michiko
M
Karita
Shuichi
S
Kimura
Tetsuya
T
Ohmiya
Kunio
K
Sakka
Kazuo
K
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D015153:Blotting, Western; D020134:Catalytic Domain / Q000235:genetics; D002686:Chitin / Q000378:metabolism; D002688:Chitinases / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular; D003013:Clostridium / Q000201:enzymology* / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D015971:Gene Expression Regulation, Enzymologic; D006026:Glycoside Hydrolases / Q000235:genetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames / Q000235:genetics; D011956:Receptors, Cell Surface / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins; C055213:saccharide-binding proteins; D002686:Chitin; D006026:Glycoside Hydrolases; D002688:Chitinases