WELKER N E, CAMPBELL L L
J Bacteriol. 1963 Dec;86(6):1196-201. doi: 10.1128/jb.86.6.1196-1201.1963.
Welker, N. E. (Western Reserve University, Cleveland, Ohio), and L. Leon Campbell. Induced biosynthesis of alpha-amylase by growing cultures of Bacillus stearothermophilus. J. Bacteriol. 86:1196-1201. 1963.-The maximal differential rate (K) of alpha-amylase synthesis was usually two to three times that of the sucrose control culture, over an inducer concentration range of 5 x 10(-4) to 1 x 10(-3)m. With maltotetraose, higher concentrations decreased the K value, whereas higher concentrations of maltose were needed to obtain maximal K values. Glucose, in concentrations from 10(-5) to 10(-2)m, had no effect on the differential rate of enzyme synthesis. Cultures growing on maltotriose, maltotetraose, maltopentaose, and maltohexaose exhibited the same growth rate (k) and differential rate of alpha-amylase synthesis over a concentration range of 2.92 x 10(-4) to 1.46 x 10(-2)m. Growth of cultures in various concentrations of pure maltose revealed that with concentrations of maltose ranging from 2.92 x 10(-3) to 1.46 x 10(-2)m the K value for alpha-amylase production increased 18-fold. The amount of maltose utilized, during the growth period, at each concentration of maltose, was constant. Diauxic type growth was observed when maltose was used in addition to another carbon source (i.e., glucose, glycerol, fructose, or sucrose). Maltose was not utilized until the other carbon source had been metabolized. Phenyl-, methyl-, and ethyl-alpha-d-glucoside and methyl-beta-d-maltoside were good inducers of alpha-amylase and would not serve as a carbon source in a chemically defined medium supplemented with 0.1% casein hydrolysate. These compounds were therefore gratuitous inducers of alpha-amylase. Isomaltose, panose, butyl-alpha-d-glucoside, and methyl-alpha-d-maltotetraoside were not effective as inducers of alpha-amylase. Fructose had an inhibitory effect on constitutive (41%) and inducible (55%) alpha-amylase formation; glucose had no effect.
韦尔克，N.E.（俄亥俄州克利夫兰市西部保留地大学），以及L.利昂·坎贝尔。嗜热脂肪芽孢杆菌生长培养物诱导合成α-淀粉酶。《细菌学杂志》86:1196 - 1201。1963年。——在诱导剂浓度范围为5×10⁻⁴至1×10⁻³m时，α-淀粉酶合成的最大差异速率（K）通常是蔗糖对照培养物的两到三倍。对于麦芽四糖，较高浓度会降低K值，而需要较高浓度的麦芽糖才能获得最大K值。浓度从10⁻⁵至10⁻²m的葡萄糖对酶合成的差异速率没有影响。在浓度范围为2.92×10⁻⁴至1.46×10⁻²m的麦芽三糖、麦芽四糖、麦芽五糖和麦芽六糖上生长的培养物表现出相同的生长速率（k）和α-淀粉酶合成差异速率。在不同浓度的纯麦芽糖中培养物的生长表明，当麦芽糖浓度范围为2.92×10⁻³至1.46×10⁻²m时，α-淀粉酶产生的K值增加了18倍。在生长期间，每种麦芽糖浓度下利用的麦芽糖量是恒定的。当除了另一种碳源（即葡萄糖、甘油、果糖或蔗糖）之外还使用麦芽糖时，观察到双相生长类型。直到其他碳源被代谢完，麦芽糖才会被利用。苯基-α-D-葡萄糖苷、甲基-α-D-葡萄糖苷和乙基-α-D-葡萄糖苷以及甲基-β-D-麦芽糖苷是α-淀粉酶的良好诱导剂，并且在添加了0.1%酪蛋白水解物的化学限定培养基中不会作为碳源。因此，这些化合物是α-淀粉酶的 gratuitous诱导剂。异麦芽糖、潘糖、丁基-α-D-葡萄糖苷和甲基-α-D-麦芽四糖苷作为α-淀粉酶的诱导剂无效。果糖对组成型（41%）和诱导型（55%）α-淀粉酶的形成有抑制作用；葡萄糖没有影响。 （注：“gratuitous”这里结合语境推测可能是“安慰性的、无需代谢利用仅起诱导作用的”之类意思，文中未明确给出准确对应中文释义）
