Changes in soluble protein, dehydrogenases, and esterases of unfertilized and fertilized eggs of Musca domestica

Abstract

The proteins, including dehydrogenases and esterases, of fertilized and unfertilized housefly eggs have been studied by acrylamide gel electrophoresis and their enzymatic activities measured. A considerable increase in the activity of lactic acid dehydrogenase (LDH) and acetylcholinesterase (AchE) was evident during embryonic development in the fertilized eggs. When the crude protein extract from the unfertilized eggs was purified by DEAE cellulose column chromatography, the activity of LDH increased but the activity of AchE remained relatively the same. The activities of malic acid dehydrogenase (MDH) and glucose-6-phosphate dehydrogenase (G-6-PDH) were similar in fertilized and unfertilized eggs. At late embryogenesis, changes in protein patterns between fertilized and unfertilized eggs were barely detectable. During the period of development five LDH isoenzymes and six esterases were found in the fertilized eggs, whereas in the unfertilized eggs two LDH isoenzymes and four esterases were found. MDH and G-6-PDH isoenzyme bands were similar in both types of eggs with two distinct isoenzyme bands near the origin.