Fluorinated substrates result in variable leakage of a reaction intermediate during catalysis by dehydroquinate synthase.

Incubation of (3S)-3-fluoro-3-deoxy-D-arabino-heptulosonate 7-phosphate with dehydroquinate (DHQ) synthase from three phylogenetically distinct sources resulted in the production of (6S)-6-fluoroDHQ and its epimer 1-epi-(6S)-6-fluoroDHQ. The differences in the product ratios of the reactions catalysed by each enzyme imply that 1-epi-(6S)-6-fluoroDHQ formation occurs by an unusual partial leakage of a reaction intermediate from the enzyme.