Purification and Characterization of Two Chitosanase Isoforms from the Sheaths of Bamboo Shoots
| Autor: | Chen-Tien Chang, Hsien-Yi Sung, Shou-Kuo Hsu, Yun-Chin Chung |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Glycoside Hydrolases
Bambusa Chitin Bambusa oldhamii Isozyme Substrate Specificity chemistry.chemical_compound Enzyme Stability Isoelectric Point Chitosanase Enzyme Inhibitors Polyacrylamide gel electrophoresis Edetic Acid Bromosuccinimide chemistry.chemical_classification Chitosan Chromatography biology Temperature Substrate (chemistry) General Chemistry Hydrogen-Ion Concentration biology.organism_classification Isoenzymes Molecular Weight Kinetics Isoelectric point Enzyme chemistry Biochemistry Metals Electrophoresis Polyacrylamide Gel General Agricultural and Biological Sciences Plant Shoots |
| Zdroj: | Journal of Agricultural and Food Chemistry. 60:649-657 |
| ISSN: | 1520-5118 0021-8561 |
| Popis: | Two thermally stable chitosanase isoforms were purified from the sheaths of chitosan-treated bamboo shoots. Isoforms A and B had molecular masses of 24.5 and 16.4 kDa and isoelectric points of 4.30 and 9.22, respectively. Using chitosan as the substrate, both isoforms functioned optimally between pH 3 and 4, and the optimum temperatures for the activities of isoforms A and B were 70 and 60 °C, respectively. The kinetic parameters K(m) and V(max) for isoform A were 0.539 mg/mL and 0.262 μmol/min/mg, respectively, and for isoform B were 0.183 mg/mL and 0.092 μmol/min/mg, respectively. Chitosans were susceptible to degradation by both enzymes and could be converted to low molecular weight chitosans between 28.2 and 11.7 kDa. Furthermore, the most susceptible chitosan substrates were 50-70 and 40-80% deacetylated for isoforms A and B, respectively. Both enzymes could also degrade chitin substrates with lower efficacy. N-Bromosuccinimide and Woodward's reagent K strongly inhibited both enzymes. |
| Databáze: | OpenAIRE |
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