Purification and characterization of thermostable beta-glucosidase from the brown-rot basidiomycete Fomitopsis palustris grown on microcrystalline cellulose
Yoon, JJ; Kim, KY; Cha, CJ
| HERO ID | 4943303 |
|---|---|
| In Press | No |
| Year | 2008 |
| Title | Purification and characterization of thermostable beta-glucosidase from the brown-rot basidiomycete Fomitopsis palustris grown on microcrystalline cellulose |
| Authors | Yoon, JJ; Kim, KY; Cha, CJ |
| Journal | Journal of Microbiology |
| Volume | 46 |
| Issue | 1 |
| Page Numbers | 51-55 |
| Abstract | An extracellular beta-glucosidase was purified 154-fold to electrophoretic homogeneity from the brown-rot basidiomycete Fomitopsis palustris grown on 2.0% microcrystalline cellulose. SDS-polyacrylamide gel electrophoresis gel gave a single protein band and the molecular mass of purified enzyme was estimated to be approximately 138 kDa. The amino acid sequences of the proteolytic fragments determined by nano-LC-MS/MS suggested that the protein has high homology with fungal beta-glucosidases that belong to glycosyl hydrolase family 3. The Kms for p-nitorophenyl-beta-D-glucoside (p-NPG) and cellobiose hydrolyses were 0.117 and 4.81 mM, and the Kcat values were 721 and 101.8 per sec, respectively. The enzyme was competitively inhibited by both glucose (Ki= 0.35 mM) and gluconolactone (Ki= 0.008 mM), when p-NPG was used as substrate. The optimal activity of the purified beta-glucosidase was observed at pH 4.5 and 70 degrees. The F. palustris protein exhibited half-lives of 97 h at 55 degrees and 15 h at 65 degrees, indicating some degree of thermostability. The enzyme has high activity against p-NPG and cellobiose but has very little or no activity against p-nitrophenyl-beta-lactoside, p-nitrophenyl-beta-xyloside, p-nitrophenyl-alpha-arabinofuranoside, xylan, and carboxymethyl cellulose. Thus, our results revealed that the beta-glucosidase from F. palustris can be classified as an aryl-beta-glucosidase with cellobiase activity. |
| Doi | 10.1007/s12275-007-0230-4 |
| Pmid | 18337693 |
| Wosid | WOS:000253545600009 |
| Is Certified Translation | No |
| Dupe Override | 4943303 |
| Is Public | Yes |
| Language Text | English |