摘要
构建重组菌(JM109/pTrc 99A xylIV)作为极耐热木聚糖酶的生产菌株,研究了IPTG诱导时间、IPTG浓度、重组菌生长的不同阶段加IPTG和温度对重组菌生产极耐热木聚糖酶的影响以及它的酶学性质.结果表明,IPTG诱导8h后极耐热木聚糖酶的表达量基本维持不变,0.5～5mmol/L浓度的IPTG诱导重组菌表达极耐热木聚糖酶的效果基本相同;当重组菌生长到OD600为1.2左右时加IPTG诱导最好,诱导温度对极耐热木聚糖酶表达水平的影响不大.重组耐热木聚糖酶的最适反应pH值为5.4～5.8,重组极耐热木聚糖酶的最适反应温度大于100℃,重组极耐热木聚糖酶在pH值4.2～7.5都比较稳定,重组极耐热木聚糖酶的温度稳定性好,在90℃下保温2h后残存酶活还有90%.
Several factors influencing thermostable xylanase production with Re-combination E. coli ( JM109/pTrc-99A-xylIV ) were investigated. The results showed that the production of thermostable xylanase did not improve after 8 hours of IPTG induction. Concentrations of IPTG from 0.5 to 5 mmol/L had the same effect on expression of thermostable xylanase. The best induced time was OD_(600) at about (1.2). The temperature from 30 ℃ to 37 ℃ did not affect the production of thermostable xylanase. The optimal reaction conditions for the thermostable xylanase were pH 5.5～5.8 at 100 ℃. The thermostable xylanase was stable at pH range of 4.2～7.2. 90% of the enzyme remained when activity incubating at 90 ℃ for 2 hours.
出处
《无锡轻工大学学报（食品与生物技术）》
CAS
CSCD
北大核心
2004年第4期94-97,共4页
Journal of Wuxi University of Light Industry
基金
国家轻工总局211专项基金
无锡市自然科学基金资助项目.
关键词
重组菌
极耐热木聚糖酶
诱导
re-combination E. coli
thermostable xylanase
induction
