[Properties of lactate dehydrogenase (LDH) during embryogenesis ofAcheta domesticus L.].

LDH activity of cricket eggs decreases during the first two days of development and then increases again with nearly constant rate. Before and after the depression of activity the molecular weight (100000), Michaelis constant (1,33 mM) and pH optimum (6.9) are identical. However, the pattern of isoenzymes and the inhibition by excess substrate are different. It is therefore assumed, that the increase of enzyme activity is due to new protein synthesis directed by the genome of the embryo cells.