Cell Division Inhibition of Arbacia and Chaetopterus Eggs and Its Reversal by Krebs Cycle Intermediates and Certain Phosphate Compounds ,

Abstract

273fered with (azide and DNP), ATP atone cannot make up the deficit. The fact that malonate is able completely to inhibit division of Arbacia and Chaetopterus eggs, and succinate and fumarate are able completely to reverse this inhibition, is strong evidence that division is intimately dependent upon a functioning Krebs cycle. Further, because ATP was unable to reverse completely the division inhibition clue to the action of malonate, the function of the Krebs cycle in division may not be completely accounted for on the basis of ' P generation. SUMMARY Division of Arbacia eggs was inhibited by low oxygen tension, cyanide, azide, dinitrophenol (DXP) and malonate. Various high and low r energy phosphate compounds, and succinate and fumarate were added to the inhibited eggs. The results were extended to malonate-inhibited Chaetopterus eggs and the effects of succinate and fumarate were noted.

A Study of the Effects of Urethan on the Cleavage of the Chaetopterus Egg. I. Inhibition of Cleavage

“…Apparently when respiration is depressed to such an extent, the eggs are unable to generate enough ATP to complete the division process (Barnett, 1953). However, urethan prevents the division of these eggs at concentrations that have little effect on respiration (for references see Krahl, 1950).…”