Zhu J, Che F, Yan Z, Liang G, Zhang S
Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
Chin J Biotechnol. 1997;13(1):25-30.
Zymograms of the cultural supernatant of Alcaligenes sp. showed three bands, the major one being G4A-1 and the minor two, G4A-2 and G4A-3. Based on the electrophoretic homogeneity of the purified three bands and the enzymatic activities identified by a thin layer chromatography of the soluble starch hydrolysates, all the three bands were confirmed to be maltotetraose-forming amylase but in multiple forms. Neither glycosidase nor protease activities could be detected in the culture (only very weak protease activities were observed at 48 hours after cultivation), which indicate that the two enzymes were not involved in the amylase multiple-form formation. Only the relative amount of the two minor bands (but not the multiple-form pattern) was changed when the initial pH of the medium varied from 6.5-8.5. An addition of 0.3% glucose raised the yield of G4A-2 and G4A-3.
产碱杆菌属菌株培养上清液的酶谱显示有三条带，主要的一条为G4A-1，另外两条次要的为G4A-2和G4A-3。基于纯化后的三条带的电泳同质性以及通过可溶性淀粉水解产物的薄层色谱法鉴定的酶活性，证实这三条带均为形成麦芽四糖的淀粉酶，但存在多种形式。在培养物中未检测到糖苷酶和蛋白酶活性（仅在培养48小时后观察到非常微弱的蛋白酶活性），这表明这两种酶不参与淀粉酶多种形式的形成。当培养基的初始pH值在6.5至8.5之间变化时，仅两条次要带的相对量（而非多种形式模式）发生了变化。添加0.3%的葡萄糖提高了G4A-2和G4A-3的产量。
