SYNTHESIS OF 3-ARSONOALANINE AND ITS ACTION ON ASPARTATE-AMINOTRANSFERASE AND ASPARTATE AMMONIA-LYASE - COMPARISON WITH ARSENICAL ANALOGS OF MALATE AND FUMARATE

DL-3-Arsonoalanine has been synthesized by the Strecker synthesis from the unstable compound arsonoacetaldehyde. It inactivates pig heart cytosolic aspartate aminotransferase and inhibits aspartate ammonia-lyase by competing with aspartate (K(i)/K(m) 0.23). The fumarate analogue (E)-3-arsonoacrylic acid and the malate analogue (RS)-3-arsonolactate also inhibit fumarate hydratase, competing with fumarate (K(i)/K(m) 1.8) and malate (K(i)/K(m) 1.6) respectively. Attempted non-enzymic transamination of 3-arsonoalanine gave elimination of arsenite, in contrast with the transamination of 3-phosphonoalanine, which is either successful or leads to loss of phosphate.