一种耐热几丁质酶的产生及其稳定性研究  

Production and Stability of a Thermostable Chitinase

作　　者：郭润芳[1] 史小琴[2] 李多川[3] 魏青[1] 贾英民[1] 

机构地区：[1]河北农业大学食品学院生物工程系,保定071000 [2]河北大学医学院,保定071001 [3]山东农业大学环境生物系,泰安271018

出　　处：《微生物学通报》2008年第4期481-485,共5页Microbiology China

基　　金：河北农业大学博士基金;河北省科技发展计划项目(No.06220106D)资助

摘　　要：疏绵状嗜热丝孢菌（Thermomyces lanuginosus）SY2在以胶状几丁质为唯一碳源的诱导培养基中产生了胞外几丁质酶。该酶在50℃保温1h，酶活稳定：65℃时半衰期为25min；酶液在室温下保存到12周，残余酶活性为45％左右。该酶有较宽的pH范围，3．0-9．0之间保持稳定，pH值为2．5时，仍具有70％的剩余酶活性。Ca^2＋对几丁质酶的活性有显著的激活作用；高浓度变性剂对酶有抑制作用。结果表明该酶是一种热稳定性高且耐酸碱的新型几丁质酶，能在酸性和高温环境中发挥作用，这些特性赋予了T.lanuginosus几丁质酶在几丁质的生物转化及其它生物技术中极大的应用优势。An extracellular chitinase from Thermomyces lanuginosus SY2 was produced when SY2 was grown in mineral liquid medium containing colloidal chitin as the only carbon source. The chitinase was stable at 50℃ for 1h, and the half-life time of the enzyme at 65℃ was 25 min. when it was kept at room temperature for 12 week, the chitinase activity was retained about 45% activity. The pH stability was kept in the range 3.0-9.0, and the enzyme was able to obtain 70% of the full activity, when the enzyme was incubated in the buffer （pH 2.5）. The chitinase activity was enhanced obviously by metal ion Ca^2＋, but inhibited under the high content chemical reagents. The results suggested that the chitinase from Thermomyces lanuginosus SY2 was a novel enzyme due to its high activity and stability under the high temperature and acid environment, which make it applicable for biotransformation and other biotechnological purposes.

关 键 词：几丁质酶 疏绵状嗜热丝孢菌 嗜热真菌 货架稳定性 

分 类 号：Q55[生物学—生物化学]