Mechanism of thermoinactivation of immobilized glucose isomerase

  title={Mechanism of thermoinactivation of immobilized glucose isomerase},
  author={David B. Volkin and Alexander M. Klibanov},
  journal={Biotechnology and Bioengineering},
Irreversible thermoinactivation of immobilized glucose isomerase from Streptomyces olivochromogenes has been mechanistically investigated at the pH‐optimum of enzymatic activity (pH 8.0). Ligands (high fructose corn syrup and the competitive inhibitor xylitol) greatly stabilize the immobilized enzyme at high temperatures. At 90°C in the presence of 2M xylitol, irreversible inactivation of immobilized glucose isomerase is caused by deamidation of its asparagine/glutamine residues. On the basis… Expand
Thermoinactivation Mechanism of Glucose Isomerase
In this article, the mechanisms of thermoinactivation of glucose isomerase (GI) from Streptomyces rubiginosus (in soluble and immobilized forms) were investigated, particularly the contributions ofExpand
Coimmobilization of glucoamylase and glucose isomerase by molecular deposition technique for one-step conversion of dextrin to fructose.
When the two enzymes were immobilized together, the system was found capable of functioning at pH 6.0 to produce fructose from starch and dextrin, and the total fructose output of the coimmobilized enzyme system after 24 h was 1.9 times that of the free enzyme system. Expand
Enhancing the Thermostability of Glucose Isomerase by Protein Engineering
The engineered recombinant glucose isomerase from Actinoplanes missouriensis is engineered by site-directed mutagenesis to enhance its thermal stability in both the soluble and immobilized forms and substitution of arginine for lysine at position 253 produced the largest stabilization under model industrial conditions. Expand
Immobilization of the serine protease from Thermomonospora fusca YX on porous glass
The immobilized protease exhibited a higher temperature optimum and pH optimum for activity compared to soluble YX‐protease and improved enzyme thermo‐stability above 90°C and reduced inactivation during prolonged storage. Expand
Influence of polymolecular events on inactivation behavior of xylose isomerase from Thermotoga neapolitana 5068.
The inactivation behavior of the xylose isomerase from Thermotoga neapolitana (TN5068 XI) was examined for both the soluble and immobilized enzyme, and formation of a reversible polymolecular aggregate capable of protecting the soluble enzyme from irreversible deactivation appears to be responsible for the second phase of inactivation seen. Expand
Extraction, purification and analysis of thermal stability of xylose isomerase
Thermostable enzymes are the enzymes which active even at high temperatures, such enzymes are industrially as well as biochemically very important. Xylose isomerase (EC is one such enzymeExpand
Efficient production of thermostable Thermus thermophilus xylose isomerase in Escherichia coli and Bacillus brevis
SummaryThe xylose (glucose) isomerase from the thermophile Thermus thermophilus seems to have potential for the development of new isomerization processes using high temperatures and slightly acidicExpand
Stability of native and cross-linked crystalline glucose isomerase.
Stabilities of native and cross-linked crystalline forms of Streptomyces rubiginosus glucose isomerase were compared in buffer and in 45% glucose/fructose solutions. The cross-linked crystalline formExpand
The immobilized enzyme on hydroxyapatite-immobilized dextransucrase could be stored in a refrigerator for 6-8 months and showed activity in 4-5 cycles of repeated use. Expand
Purification and characterization of a highly thermostable glucose isomerase produced by the extremely thermophilic eubacterium, Thermotoga maritima
  • Stephen H. Brown, C. Sjøholm, Robert M. Kelly
  • Biology, Medicine
  • Biotechnology and bioengineering
  • 1993
The high degree of thermostability, coupled with a neutral to slightly acid pH optimum, reveal this enzyme to be a promising candidate for improvement of the industrial glucose isomerization process. Expand


Sweetzyme — A New Immobilized Glucose Isomerase
The enzymatic isomerization of glucose to fructose is attracting significant attention from scientific as well as industrial quarters. In recent years, high fructose syrups (“isosyrups”) produced byExpand
Substrate protection of immobilized glucose isomerase
Using commercial immobilized glucose isomerase (SWETASE®, Nagase Co.), the effect of substrate protection on enzyme deactivation has been studied in a batch manner and the protection factor was proposed to elucidate the dependence of the degree of substrateprotection. Expand
Glucose isomerase immobolized on porous glass
Partially purified glucose isomerase from a Streptomyces species was immobilized on porous glass particles and studied for various characteristics concerning its use as an industrial catalyst. TheExpand
Control of oligomeric enzyme thermostability by protein engineering.
It is shown that replacement of interfacial Asn-78 by an aspartic acid residue increases the rate constant of irreversible thermal inactivation, drastically decreases the reversible transition temperature, and reduces the stability against dilution-induced dissociation. Expand
Why does ribonuclease irreversibly inactivate at high temperatures?
The mechanism of irreversible thermoinactivation of bovine pancreatic ribonuclease A in the pH range relevant to enzymatic catalysis has been elucidated and four processes appear to demarcate the upper limit of thermostability of enzymes. Expand
Purification, Immobilization, and Some Properties of Glucose Isomerase from Streptomyces flavogriseus
Several differences in properties were found between purified soluble enzyme, immobilized enzyme (DEAE-cellulose-glucose isomerase), and heat-treated whole cells, including a greater heat stability than whole cells. Expand
The mechanisms of irreversible enzyme inactivation at 100C.
The mechanism of irreversible thermoinactivation of an enzyme has been quantitatively elucidated in the pH range relevant to enzymatic catalysis. The processes causing irreversible inactivation ofExpand
Roles of Magnesium and Cobalt in the Reaction of Glucose Isomerase from Streptomyces griseofuscus S-41
The roles of magnesium and cobalt ions in the reaction of glucose isomerase from Streptomyces griseofuscus S-41 were kinetically investigated. Magnesium was superior to cobalt as an activator, butExpand
Mechanisms of irreversible thermal inactivation of Bacillus alpha-amylases.
Molecular mechanisms of irreversible thermal inactivation of two bacterial alpha-amylases, from the mesophile Bacillus amyloliquefaciens and from the thermophile Bacillus stearothermophilus, haveExpand
Physico-chemical and Enzymatic Properties of Purified Glucose Isomerases from Streptomyces olivochromogenes and Bacillus stearothermophilus
Large differences were found in the amino acid compositions of these two enzymes, especially in their serine, proline, tyrosine, lysine and arginine contents. Expand