The effects of temperature and chorionic gonadotropin on the functional properties of lactate dehydrogenase from oocytes of loach Misgurnus fossilis

Abstract Acclimation of loach to relatively low and high temperatures gives rise to changes in the properties of LDH from oocytes. The minimum of apparent K m values for pyruvate of LDH from immature oocytes of fish acclimated to low temperature was registered at low assay temperatures, whereas adaptation to high temperatures leads to the enzyme showing a minimum at high temperatures. In thermal acclimation of fish the K m minimum value drifts during 15 days. During oocyte maturation, the K m minimum drifts during 40 hr. The differences in the kinetic features of LDH from oocytes both at thermal acclimation and during oocyte maturation are not associated with the appearance of new isozymes.