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

• Published in: FEBS letters Vol. 282; no. 1; pp. 122 - 126
• Main Authors: Schumann, Judith, Wrba, Alexander, Jaenicke, Rainer, Stetter, Karl Otto
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 22-04-1991; Elsevier
• Subjects: Amylase; Amylases - isolation & purification; Amylases - metabolism; Bacillus - enzymology; Bacillus licheniformis; Chromatography, Affinity; Compartmentation; Cyclodextrins - metabolism; Electrophoresis, Polyacrylamide Gel; Exact sciences and technology; Gram-Negative Anaerobic Bacteria - enzymology; Hydrogen-Ion Concentration; Mathematical analysis; Mathematics; Potential theory; Sciences and techniques of general use; Substrate Specificity; Temperature; Thermophilic; Thermotoga maritima; Thermophilic; Amylase; Compartmentation; Bacillus licheniformis; Thermotoga maritima; Molecular form; Purification; Enzyme; Bacillaceae; Characterization; Bacillales; Enzymatic activity; Substrate specificity; Bacteria; Localization; Comparative study
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(91)80459-G

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.