Enhancement of stability of immobilized glucose oxidase by modification of free thiols generated by reducing disulfide bonds and using additives.
Stability of glucose oxidase (GOD) immobilized with lysozyme has been considerably enhanced by modification of free thiols generated by reducing disulfide bonds using beta-mercaptoethanol and N-ethylmaleimide in conjunction with additives like antibiotics and salts. Thermal stability of immobilized GOD was quantified by means of the transition temperature, Tm and the operational stability by half-life t1/2 at 70 degrees C. Modification of the free thiols in the enzyme coupled with the presence of kanamycin, NaCl, and K2SO4, led to increase in Tm, to 80, 82 and 84 degrees C (compared to 75 degrees C in control) and t1/2 by 7.7-, 11- and 22-fold, respectively, indicating that this method can be effectively used for enhancing the stability of enzymes.
Gulla
K C
KC
Department of Fermentation Technology and Bioengineering, Central Food Technological Research Institute, Mysore 570013, India.
Gouda
M D
MD
Thakur
M S
MS
Karanth
N G
NG
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry*; D004566:Electrodes; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005609:Free Radicals / Q000737:chemistry; D005949:Glucose Oxidase / Q000737:chemistry*; D010084:Oxidation-Reduction; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013696:Temperature
D020099:Coated Materials, Biocompatible; D004220:Disulfides; D004800:Enzymes, Immobilized; D005609:Free Radicals; D013438:Sulfhydryl Compounds; D005949:Glucose Oxidase