Mutations Asn20-->Cys/Ala27-->Cys (SS), Ala27-->Pro, Ser30-->Pro, Lys108-->Arg, Gly137-->Ala, Tyr312-->Trp and Ser436-->Pro in Aspergillus awamori glucoamylase, along with a mutation inserting a seven-residue loop between Tyr311 and Gly314 (311-314 Loop), were made to increase glucose yield from maltodextrin hydrolysis. No active Lys108-->Met glucoamylase was found in the supernatant after bein...

A glucoamylase-immobilized system based on cross-linked gelatin nanoparticles (CLGNs) was prepared by coacervation method. This system exhibited characteristics of temperature-triggered phase transition, which could be used for enzyme immobilization and release. Their morphology and size distribution were examined by transmission electron microscopy and dynamic light scattering particle size an...

To understand the differences in production and secretion patterns between plasmid-harboring and chromosome-integrated recombinant yeasts, the two recombinant Saccharomyces cerevisiae yeasts, containing the structural glucoamylase STA gene and the SUC2 promoter, were investigated. Both systems were regulated by glucose concentration in the culture broth. First, the glucoamylase activity per gen...

Arthrobotrysamerospora (ATCC 34468) produced glucoamylase in a semi-synthetic medium containing starch as a sole carbon source. Polyacrylamide gel electrophoresis of crude glucoamylase showed three isoenzymes. They were designated as glu I, glu II and glu III according to their electrophoretic mobility. These iso-glucoamylases were purified by column chromatography using DEAE-Sephadex A-50. The...

Bestimmung der Glucoamylase in Kulturfiltraten, die andere amylolytische Enzyme enthalten. Es wird eine verbesserte Methode fur die bestimmung der Glucoamylase in Gegenwart anderer amylolytischer Enzyme vorgeschlagen. Sie beruht auf der Verwendung von Dextran mit niedrigem Molekulargewicht als spezifisches Substrat. Die Bestimmung der aktivitat erfolgt durch quantitative Ermittlung der Glucosem...

Digestion of starch requires activities provided by 6 interactive small intestinal enzymes. Two of these are luminal endo-glucosidases named alpha-amylases. Four are exo-glucosidases bound to the luminal surface of enterocytes. These mucosal activities were identified as 4 different maltases. Two maltase activities were associated with sucrase-isomaltase. Two remaining maltases, lacking other i...

Two additional disulfide bonds and three combined thermostabilizing mutations were introduced into Aspergillus awamori glucoamylase to test their effects on enzyme thermostability and catalytic properties. The single cysteine mutations N20C, A27C, T72C and A471C were made and combined to produce the double cysteine mutations N20C/ A27C and T72C/A471C. The double cysteine mutants were expressed ...

30. Chantret I, Lacasa M, Chevalier G, et al. Sequence of the complete cDNA and the 50 structure of the human sucrase-isomaltase gene. Possible homology with a yeast glucoamylase. Biochem J 1992; 285:915–23. 31. Nichols BL, Eldering J, Avery S, et al. Human small intestinal maltaseglucoamylase cDNA cloning. Homology to sucrase-isomaltase. J Biol Chem 1998;273:3076–81. 32. Nichols BL, Avery S, S...

Digestion of starch requires activities provided by 6 interactive small intestinal enzymes. Two of these are luminal endoglucosidases named a-amylases. Four are exo-glucosidases bound to the luminal surface of enterocytes. These mucosal activities were identified as 4 different maltases. Two maltase activities were associated with sucrase-isomaltase. Two remaining maltases, lacking other identi...

Transformed, hybrid Saccharomyces strains capable of simultaneous secretion of glucoamylase and alpha-amylase have been produced. These strains could carry out direct, one-step assimilation of starch, with conversion efficiency greater than 93% during a 5-day growth period. One of the transformants converted 92.8% of available starch into reducing sugars in only 2 days. Glucoamylase secretion b...