Effects of 2-amino-4-hydroxy-6-carboxy-7,8-dihydropteridine and 2-amino-4-hydroxy-6-formyl-7,8-dihydropteridine on growth of Escherichia coli.

2-Amino-4-hydroxy-6-carboxy-7, 8-dihydropteridine inhibited growth of Escherichia coli B, while 2-amino-4-hydroxy-6-carboxypteridine did not affect the growth. The half inhibition was achieved with the inhibitor concentration of 2.2×10-4M. The inhibition could be reversed by 2-amino-4-hydroxy-6-formyl-7, 8-dihydropteridine. However, when the carboxydihydropteridine was absent in the culture medium, the formyldihydropteridine blocked the microbial growth with an inhibitory power about equal to the carboxydihydropteridine.