| Abstract: | The kinetics of the synthesis of a riboflavin (RF) precursor, 2,6-dihydroxy-5-amino-4-ribitylaminopyrimidine (DHARAP), was studied using the washed cells of RF-deficient mutants of Pichia guilliermondii R7G and Pichia ohmeri R32 with blocked lumasine synthetase. RF inhibited the synthesis of DHARAP while cycloheximide in the absence of RF had no effect on this process. The data suggest that flavins regulate the biosynthesis of RF in P. guillier mondii and P. ohmeri b7 means of feed-back inhibition mechanism. |
