Topographical and enzymatic characterization of amylases from the extremely thermophilic eubacterium Thermotoga maritima

FEBS Letters

Jaenicke, Rainer²  Stetter, Karl Otto²  Wrba, Alexander¹  Schumann, Judith¹ 

[1] Institut für Biophysik und Physikalische Biochemie, Universität Regensburg, D-8400 Regensburg, Germany;Lehrstuhl Mikrobiologie, Universität Regensburg, D-8400 Regensburg, Germany

关键词: Amylase;    Bacillus licheniformis;    Compartmentation;    Thermophilic;    Thermotoga maritima;   

DOI  :  10.1016/0014-5793(91)80459-G

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The hyperthermophilic cubacterium Thermotoga maritima uses starch as a substrate, without releasing amylase activity into the culture medium. The enzyme is associated with the ‘toga’. Its expression level is too low to allow the isolation of the pure enzyme. Using cycloheptaamylose and acarbose affinity chromatography and common chromatographic procedures, two enzyme fractions are obtained. They differ in specificity, pH-optimum, temperature dependence and stability. Substrate specificity and Ca^2* dependence indicate α-, β- and gluco-amylase activity. Compared with α-amylase from Bacillus licheniformis (T _max = 75°C), the amylasex from Thermotoga maritima show exceedingly high thermal stability with an upper temperature limit at 95°C. Significant turnover occurs only 70 and 100°C, i.e. in the range of viability of the microorganism.

【 授权许可】

Unknown