Welker N E, Campbell L L
J Bacteriol. 1967 Oct;94(4):1131-5. doi: 10.1128/jb.94.4.1131-1135.1967.
The alpha-amylase (alpha-1,4-glucan 4-glucanohydrolase, EC 3.2.1.1) of Bacillus subtilis strain W23 is less negatively-charged than the alpha-amylase of B. amyloliquefaciens strain F, as determined by electrophoretic mobility in polyacrylamide gel at pH 8.6. The alpha-amylase of strain W23 is immunologically unrelated to the alpha-amylase of strain F, as judged by lack of cross-reaction in Ouchterlony immunodiffusion studies. The pH range of maximal activity for the enzyme of strain W23 was 5.7 to 6.7, with a maximum at 6.3. The pH range of activity for the alpha-amylase of strain F was 5.5 to 6.5, with a maximum at 5.9. No significant difference was found in the effect of temperature on the activity of the alpha-amylase of strain W23 and strain F. alpha-Amylase production by strain W23 occurs throughout the 7-hr growth period, whereas enzyme production by strain F does not begin until the culture enters the stationary phase of growth. The total amounts of enzyme produced by strains W23 and F after 7 hr of growth were 0.3 and 25.5 units/ml, respectively.
在pH 8.6的聚丙烯酰胺凝胶中通过电泳迁移率测定，枯草芽孢杆菌W23菌株的α-淀粉酶（α-1,4-葡聚糖4-葡聚糖水解酶，EC 3.2.1.1）比解淀粉芽孢杆菌F菌株的α-淀粉酶带负电荷少。在双向免疫扩散研究中，通过缺乏交叉反应判断，W23菌株的α-淀粉酶与F菌株的α-淀粉酶在免疫上不相关。W23菌株的该酶最大活性的pH范围为5.7至6.7，最大值在6.3。F菌株的α-淀粉酶的活性pH范围为5.5至6.5，最大值在5.9。未发现温度对W23菌株和F菌株的α-淀粉酶活性的影响有显著差异。W23菌株在整个7小时的生长期间都产生α-淀粉酶，而F菌株直到培养物进入生长稳定期才开始产生该酶。生长7小时后，W23菌株和F菌株产生的酶总量分别为0.3和25.5单位/毫升。
