Irreversible thermal denaturation of glucose oxidase from Aspergillus niger is the transition to the denatured state with residual structure.

Irreversible thermal denaturation of Glucose oxidase from Aspergillus niger

Thermal Characterization of Purified Glucose Oxidase from A Newly Isolated Aspergillus Niger UAF-1

An intracellular glucose oxidase was isolated from the mycelium extract of a locally isolated strain of Aspergillus niger UAF-1. The enzyme was purified to a yield of 28.43% and specific activity of 135 U mg(-1) through ammonium sulfate precipitation, anion exchange and gel filtration chromatography. The enzyme showed high affinity for D-glucose with a Km value of 2.56 mM. The enzyme exhibited ...

Formation of molten globule-like state during acid denaturation of Aspergillus niger glucoamylase

Acid denaturation of Aspergillus niger glucoamylase was studied using different conformational probes. Both far-UV CD spectral signal (MRE222 nm) and tryptophan fluorescence remained unchanged in the pH range, 7.0–3.0 but decreased significantly below pH 3.0, whereas ANS fluorescence showed a marked increase below pH 1.5. Maximal changes in MRE222 nm and ANS fluorescence were noticed at pH 1.0....

Two-state irreversible thermal denaturation of Euphorbia characias latex amine oxidase.

Thermal denaturation of Euphorbia latex amine oxidase (ELAO) has been studied by enzymatic activity, circular dichroism and differential scanning calorimetry. Thermal denaturation of ELAO is shown to be an irreversible process. Checking the validity of two-state it really describes satisfactorily the thermal denaturation of ELAO. Based on this model we obtain the activation energy, parameter T(...

REASSOCIATION AND REACTIVATION OF GLUCOSE 6-PHOSPHATE DEHYDROGENASE FROM STREPTOMYCES AUREOFACIENS AFTER DENATURATION BY 6 M UREA

Glucose 6-phosphate dehydrogenase (G6PD) from Streptomyces aureofaciens was purified and denatured in 6 M urea. Denaturation led to complete dissociation of the enzyme into its inactive monomers, 98% loss of the enzyme activity, about 30% decrease in the protein fluorescence and a 10 nm red shift in the emission maximum. Dilution of urea-denatured enzyme resulted in regaining of the enzyme acti...