[Purification of exocellular catalise of Penicillium piceum F-648 and enzyme]
2003
Moroz, I.V. | Pavlovskaya, Zh.I. | Mikhajlova, R.V. | Eremin, A.N. (Institute of Microbiology of the National Academy of Sciences of Belarus, Minsk (Belarus))
Four fractions (fr.) of extracellular catalase, which had high helix content, were isolated from the cultural liquid of Penicillium piceum F-648 and then purified with the help of the ultrafiltration membranes which featured 0.2 mm diameter pores and detention limits of 300, 50 and 20 kDa respectively. When the catalase concentration in a reaction medium was less than 1 nM, all the enzyme samples except fr.3 decomposed H2O2 at the approximately the same rate. When the catalase concentration was more than 1 nM, the largest catalytic activity was displayed by the fr.2 obtained on the membrane with the detention limit of 50 kDa. Kinetic parameters of extracellular catalase depened on its concentration in a reaction medium. In strongly diluted solutions the catalase was characterised by the largest values of the effective catalytic constant and the constant which shows the interaction of Complex I with H2O2 second molecule. Under these conditions the extracellular catalase P. piceum F-648 dislayed low operational stability, that increased significantly with the rise of the catalase concentration in a medium. The optimum enzyme concentration in solution was equal 1.5 - 2.0 nM
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