[Application of ultrafiltration for concentration and purification of Penicillium vitale catalase].

Various factors are studied for their effect on the ultrafiltration of Penicillium vitale catalase. It is established that acetate cellulose and polyamide membranes may be used for additional purification and deep concentration of native preliminarily purified enzyme solutions. Membranes YAM-300 and YAM-450 are most preferable.

[Immobilization of Penicillium vitale catalase on aminoethyl cellulose and properties of the obtained preparations].

Preparations of Penicillium vitale catalase immobilized by aminoethyl cellulose (AE-cellulose) are obtained using two methods: by the enzyme covalent cross-linking with the carrier by glutaric aldehyde and by the covalent binding of catalase to the carrier aminogroups through the carbohydrate enzyme component. A dependence is established for the degree of catalase binding and catalase activity of the immobilized enzyme on the enzyme carrier in immobilization ratio. The optimal enzyme-carrier ratio in both cases is 10 mg of the enzyme per 1 g of the carrier.

[Immobilization of Penicillium vitale glucose oxidase by aminoethyl cellulose and properties of immobilized enzyme].

Penicillium vitale glucose oxidase modified by oxidation of the carbohydrate component is in a covalent combination with aminoethyl cellulose (AE-cellulose). With the optimal enzyme: carrier ratio the manifested activity of glucose oxidase in the preparation is 4.3 +/- 0.

[Immobilization of Penicillium vitale glucose-oxidase on aminosilochrome and properties of immobilized enzyme].

Penicillium vitale glucose-oxidase modified by means of the carbohydrate component oxidation is added covalently to aminoorganosylochrome. The activity of the immobilized preparations is 20-38% depending on the protein-carrier ration in immobilization. Comparison of some properties of native and immobilized glucose-oxidase showed that the rH optimum of the immobilized glucose-oxidase is slightly widened towards the alkaline regions; the immobilized glucose-oxidase possesses a considerably higher pH-stability at pH alkaline values; the immobilized glucose-oxidase preparations are characterized by a significantly greater thermostability: their thermoinactivation constant at 65 degrees C is 8-10 times lower than that of the native enzyme.

[Stabilizing effect of calcium ions on glucose oxidase of Penicillium vitale].

Reconstruction of P. vitale glucose oxidase from apeonzyme and coenzyme (FAD) was studied as affected by iodine acetate as well as mercury and calcium ions. Mercury ions, iodine acetate as well as the labilizing fraction (flavin adenine-containing component) are established to inhibit the reconstruction affecting the sulphydryl groups of the apoenzyme which take part in addition of FAD to it.