三株异淀粉酶酶源菌株的筛选分离及部分酶学性质研究  

Isolation of Three Bacillus Strains and Characterization of Their Isoamylase

作　　者：王晓燕[1,2,3,4] 李俊俊[2,3,4] 杨云娟[2,3,4] 唐湘华[2,3,4] 孟艳芬[2,3,4] 许波[2,3,4] 黄遵锡[1,2,3,4] 

机构地区：[1]中国农业大学水利与土木工程学院,北京100193 [2]生物能源持续开发利用教育部工程研究中心,云南昆明650092 [3]云南师范大学酶工程重点实验室,云南昆明650092 [4]云南师范大学生命科学学院,云南昆明650092

出　　处：《食品与发酵工业》2010年第6期31-35,共5页Food and Fermentation Industries

基　　金：云南省应用基础研究计划重点项目:热泉中高温酶功能基因研究与评价(2006C004Z)

摘　　要：从云南温泉中分离鉴定了3株产异淀粉酶的芽孢杆菌，经16SrDNA序列比对分析及主要生理生化研究，初步鉴定为：Bacillus amyloliquefacie LCEP-1、Bacillus subtilis DL-34—2、Bacillus subtilis DMJS-2—1。GeneBank登录号分别为：gb．GQ199589、gb．GQ199593、gb．GQ199594。3株菌所产的异淀粉酶都能降解玉米支链淀粉。酶解反应的最适pH分别为pH6．8、5．4和pH7．8；最适温度分别为60、55、60℃。优化条件下，最高酶活分别为：36．5、18．89、11．08μ／mL。3株菌的酶对不同金属离子有不同的反应，金属螯合剂EDTA对酶活又有较强的抑制作用，推测可能都属于金属酶。3株菌能在偏酸性至中性的pH范围内（pH4．4～8．0）保持稳定，可以在pH变化较大的条件下保持较高的酶活，在偏酸性、中性和弱碱性环境中都能有效地水解淀粉质底物。3株菌所产异淀粉酶，底物专一性强，最适pH可低至5．4。To determine the physiological and biochemical characteristics, three Bbacillus strains were isolated from Yunnan springs and were identified by 16 SrDNA sequence analysis as Bacillus amyloliquefacie LCEP-1 ,Bacillus subtilis DL-3-4-2 and Bacillus subtilis DMJS-2-1 with their GeneBank accession numbers of gb. GQ199589, gb. GQ199593 and gb. GQ199594, respectively. Isoamylases from all three strains could hydrolyze corn amylopectin. The optimal pH of enzymatic reaction respectively was 6. 8, 5.4 and 7.8; optimum temperature was 60℃ , 55℃ and 60℃. Under optimized conditions, the highest enzyme activity was 36.5 U/mL, 18.89 U/mL and 11.08 U/mL. The enzymes react differently to metal ions. It is proposed that the three isoamylases belong to metal enzymes because some metal and EDTA showed stronger inhibitory effect than others on the enzyme activity. Within the pH range of 4.4 8.0 all three enzymes remain stable; the enzyme activities can maintain high under the condition of weak acidic,neutral to weak alkaline.

关 键 词：异淀粉酶 菌株筛选 酶学性质 

分 类 号：Q814[生物学—生物工程]