Characterization of a gene encoding cellulase from uncultured soil bacteria.
FEMS Microbiol Lett
; 282(1): 44-51, 2008 May.
Article
em En
| MEDLINE
| ID: mdl-18355282
ABSTRACT
To detect cellulases encoded by uncultured microorganisms, we constructed metagenomic libraries from Korean soil DNAs. Screenings of the libraries revealed a clone pCM2 that uses carboxymethyl cellulose (CMC) as a sole carbon source. Further analysis of the insert showed two consecutive ORFs (celM2 and xynM2) encoding proteins of 226 and 662 amino acids, respectively. A multiple sequence analysis with the deduced amino acid sequences of celM2 showed 36% sequence identity with cellulase from the Synechococcus sp., while xynM2 had 59% identity to endo-1,4-beta-xylanase A from Cellulomonas pachnodae. The highest enzymatic CMC hydrolysis was observable at pH 4.0 and 45 degrees C with recombinant CelM2 protein. Although the enzyme CelM2 additionally hydrolyzed avicel and xylan, no substrate hydrolysis was observed on oligosaccharides such as cellobiose, pNP-beta-cellobioside, pNP-beta-glucoside, and pNP-beta-xyloside. These results showed that CelM2 is a novel endo-type cellulase.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Microbiologia do Solo
/
Bactérias
/
Celulase
País como assunto:
Asia
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article