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.