Effect of pyronin Y on adenovirus.

Abstract

At concentrations (10–15 μM) not markedly toxic for the eta line of rhesus monkey kidney cells, commercial pyronin Y, at low to moderate pH values, strongly inhibited the cytopathic effects and multiplication, of human type 1 adenovirus on these cells. The inhibition occurred equally in the dark and under ordinary light conditions, and was readily reversible simply by replacing the old medium with fresh medium without pyronin Y. The major colored component of the commercial pyronin Y, purified by paper chromatography, was found to possess nearly full activity. High concentrations (5–50 mM) of pyronin Y inactivated adenovirionsin vitro, especially at low pH, and equally in the dark as in ordinary room light; but the low concentrations which inhibit adeno-virus multiplication did not inactivate virions. Adenovirus synthesized in the presence of pyronin Y was stable to room light. Serial passages of adenovirus in the presence of pyronin Y did not result in the emergence of resistant mutants.