Fungal biosynthesis of 3-nitropropanoic acid
Abstract
The origin of 3-nitropropanoic acid 1 in the fungus Penicillium atrovenetum has been examined using a combination of stable isotope methods. The incorporation of 13C and 15N from DL-[2-13C, 15N]aspartic acid 2a,18O from 18O2,15N from DL-diethyl [15N] nitrosuccinate 6 and 2H from L-[2,3,3-2H3]aspartate, DL-[4-13C, 2,3,3-2H3]aspartate and from (2S,3R)-[3-2H]- and (2S,3S)-[2,3-2H2]-aspartates indicate a biosynthetic pathway L-aspartate 2→(S)-nitrosuccinate 5→1. Mature cells of P. atrovenetum which produce 3-nitropropanoate dehydrogenase catalyse an apparent futile cycle between 1 and 3-nitroacrylate 3 with loss of the stereospecific integrity of the hydrogen at the 2-position of 1.