Dual inhibitory effect of bredinin

Abstract
Bredinin inhibition of cell growth was investigated in the mouse lymphoma cell line L5178Y. Bredinin caused the accumulation of IMP and the reduction of XMP. It was converted to the 5′‐phosphate within the cells. Bredinin 5′‐phosphate but not bredinin competitively inhibited both IMP dehydrogenase and GMP synthetase. Thus the inhibition of cell growth is probably due to bredinin 5′‐phosphate, which inhibits the consecutive enzyme reactions IMP dehydrogenase and GMP synthetase. These inhibitions result in the accumulation of IMP and the reduction of XMP.