Production and Characterization of Thermotolerant Endoglucanase from Streptomyces xylophagus KX6 / 中国生物工程杂志

ABSTRACT

A strain KX6,producing thermotolerant endoglucanase,was isolated from compost. The morpholo-gical identification and 16S rRNA sequence analysis showed it belongs to Streptomyces xylophagus. The production and characterization of endoglucanase from Streptomyces xylophagus KX6 was studied. Maximum endoglucanase yield of 0.538 IU/ml was achieved with medium pH8.0,containing CMC2Na 1.0% as carbon resource,soybean meal 1% as nitrogen resource,2% inoculating volume,30% 250 ml triangle flask bulk for medium volume at 40℃ 200r/min shaker for 48h. The endoglucanase exhibited optimum catalytic activity at pH7.0 and 50℃. The enzyme was stable at 50℃,and able to retain 60% of the full activity,when it was incubated at 60℃ for 1h.The enzyme was stable at pH6.0~7.0. All these findings suggest that the enzyme is a thermotolerant neutral endoglucanase.