Primary study on isolation of cellulase from a Thermobifida and its enzymatic properties
Nucleotide sequences of the 16S rRNA gene of Thermobifida (formerly Thermomonospora) Q-0 was analyzed by MEGA v.3, and the phylogenetic tree showed the relationship between different strains in Thermobifida genus. A carboxymethyl cellulase Ⅰ (CMCase Ⅰ ) was purified by fractional ammonium sulphate precipitation and ion exchange chromatography on DEAE-Sephadex. The enzyme showed the highest activity at 60°C and pH 8.0.It exhibited high thermostability and wide pH stability (6.0 -9.0). The enzyme retained 100％ activity at 50°C for 120min. The half-lives of the CMCase at 70°C and 80°C were about 75min and 110min, respectively. The effects of some metal ions and inhibitors on the activities of the CMCases were examined. Metal ions such as K+, Na+, Cu2+, Fe3+ did not influence the enzyme activity. Mg2+ ions caused increase, while Hg2+, Mn2+, Ag2+, Zn2+, caused a decrease in the activity. Ca2+ was slightly inhibitory to CMCase. The enzyme activity was complete inhibited by EDTA, which indicated the enzyme activity required certain metal ions for activation and stabilization.
actinomycetes Thermobifid carbozymethyl cellulase
Qi Yun Liao Yin-zhang
School of Environmental Science and Engineering Tianjin University Tianjin,China Chengdu Institute of biology chinese Academy of Sciences Chengdu,China
国际会议
北京
英文
1-4
2009-06-11（万方平台首次上网日期，不代表论文的发表时间）