Synthesis of DNA in permeabilized cells of Kiuyveromyces lactis

Abstract

Kluyveromyces lactis cells permeabilized with nystatin, though no longer viable, were able to incorporate ³ H-dATP into DNA. Maximum rate of synthesis was obtained when all four de oxyribonucleoside triphosphates were present. For prolonged incorporation of ³ H-dATP into DNA rATP or phosphoenolpyruvate were of absolute requirement. DNA synthesis was inhibited by p-chloromercuribenzoate, N-ethylmaleimide, nalidixate, ethi dium bromide and distamycin A. The density of DNA synthesized in permeabilized cells grown on non-fermentable and fermentable carbon sources was analyzed on CsCl gradients in the presence or absence of distamycin A. The DNA synthesized by per meabilized cells previously grown on glycerol was essentially mitochondrial DNA; nuclear DNA (30% of total) was also synthesized by cells previously grown on glucose.