Autor: |
Ya-Min Chang, Li-Chun Chen, Hsin-Yi Wang, Chui-Liang Chiang, Chen-Tien Chang, Yun-Chin Chung |
Jazyk: |
angličtina |
Rok vydání: |
2014 |
Předmět: |
|
Zdroj: |
PLoS ONE, Vol 9, Iss 12, p e113596 (2014) |
Druh dokumentu: |
article |
ISSN: |
1932-6203 |
DOI: |
10.1371/journal.pone.0113596 |
Popis: |
Using 4-methylumbelliferyl-β-D-N,N',N″-triacetylchitotrioside (4-MU-GlcNAc3) as a substrate, an acidic chitinase was purified from seeds of black soybean (Glycine max Tainan no. 3) by ammonium sulfate fractionation and three successive steps of column chromatography. The purified chitinase was a monomeric enzyme with molecular mass of 20.1 kDa and isoelectric point of 4.34. The enzyme catalyzed the hydrolysis of synthetic substrates p-nitrophenyl N-acetyl chitooligosaccharides with chain length from 3 to 5 (GlcNAcn, n = 3-5), and pNp-GlcNAc4 was the most degradable substrate. Using pNp-GlcNAc4 as a substrate, the optimal pH for the enzyme reaction was 4.0; kinetic parameters Km and kcat were 245 µM and 10.31 min-1, respectively. This enzyme also showed activity toward CM-chitin-RBV, a polymer form of chitin, and N-acetyl chitooligosaccharides, an oligomer form of chitin. The smallest oligomer substrate was an N-acetylglucosamine tetramer. These results suggested that this enzyme was an endo-splitting chitinase with short substrate cleavage activity and useful for biotechnological applications, in particular for the production of N-acetyl chitooligosaccharides. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
|