Characterisation of cellulose-hydrolysing enzymes from the fungusBipolaris sorokiniana

✍ Scribed by Geimba, Mercedes P; Riffel, Alessandro; Agostini, Viviane; Brandelli, Adriano

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 105 KB
• Volume: 79
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/(sici)1097-0010(199910)79:13<1849::aid-jsfa445>3.0.co;2-4

✦ Synopsis

Cellulose-hydrolysing enzymes from the phytopathogenic fungus Bipolaris sorokiniana were partially puri®ed and characterised. The enzyme production was variable according to the carbon source. b-Glucosidase and cellobiohydrolase activities were higher by growing the fungus on cellulose than on other carbon sources. Carboxymethyl cellulase production was stimulated by other carbohydrates, mainly lactose. Partial enzyme puri®cation was carried out by liquid chromatography on Sepharose CL4B. The puri®cation was about 17-fold, with a yield of 41% as judged by assay with p-nitrophenyl-b-D-glucopyranoside as substrate. The optimum pH and temperature were 5.0 and 55±60 °C respectively. The enzyme was stable at 28 and 37 °C but lost about 50% of its initial activity after 120 min at 55 °C. Sacchari®cation of cellulosic materials such as crystalline cellulose, ®lter paper and wheat straws was carried out using the partially puri®ed enzyme, resulting in the production of reducing sugars.