It has been estimated that less than 1% of the microorganisms in nature can be cultivated by conventional techniques. Thus, the classical approach of isolating enzymes from pure cultures allows the analysis of only a subset of the total naturally occurring microbiota in environmental samples enriched in microorganisms. To isolate useful microbial enzymes from uncultured soil microorganisms, a m...

Cyclodextrin glycosyltransferase (CGTase) enzymes from various bacteria catalyze the formation of cyclodextrins from starch. The Bacillus stearothermophilus maltogenic alpha-amylase (G2-amylase is structurally very similar to CGTases, but converts starch into maltose. Comparison of the three-dimensional structures revealed two large differences in the substrate binding clefts. (i) The loop form...

BACKGROUND Maltogenic amylases belong to a subclass of cyclodextrin-hydrolyzing enzymes and hydrolyze cyclodextrins more efficiently than starch unlike typical α-amylases. Several bacterial malto-genic amylases with temperature optima of 40-60°C have been previously characterized. The thermo-adaption, substrate preferences and transglycosylation aspects of extremely thermostable bacterial malto...

The thermostability of maltogenic amylase from Thermus sp. strain IM6501 (ThMA) was improved greatly by random mutagenesis using DNA shuffling. Four rounds of DNA shuffling and subsequent recombination of the mutations produced the highly thermostable mutant enzyme ThMA-DM, which had a total of seven individual mutations. The seven amino acid substitutions in ThMA-DM were identified as R26Q, S1...

Enzymatic modification is an effective method to inhibit starch retrogradation. However, lack of quantification relationships between enzymatic and retrogradation makes the improvement unpredictable. In this study, maltogenic α-amylase (MA) was used treat wheat granules restrain retrogradation, aiming elucidate mechanism MA hydrolysis on establish a quantitative relationship degree (DH) Scannin...

Maltogenic amylase (Mag1) is a potent enzyme that hydrolyzes the glycosidic bond of polysaccharides to produce malto-oligosaccharides (MOS). However, Mag1 has poor stability and reusability, leading inefficient MOS production. Enzyme immobilization promising method solve problem. Entrapment encapsulation technique was used in this study immobilize because high biocompatibility prevention degrad...