Abstract
Thiouracil inhibited the growth of psittacosis virus (6BC) in tissue cultures at concns. which had no obvious toxic effects on the host tissues. In tolaterated amts. 6-methylthiouracil, 6-methyluracil, diazouracil, and uracil had no effect on virus growth. These experiments suggest that some aspect of the intracellular metabolism of uracil is essential for the multiplication of psittacosis virus (6BC).