Studies of 1‑Amino-2,2-difluorocyclopropane-1-carboxylic Acid: Mechanism of Decomposition and Inhibition of 1‑Aminocyclopropane-1-carboxylic Acid Deaminase

1-Amino-2,2-difluoro­cyclopropane-1-carboxylic acid (DFACC) is of interest in the study of 1-aminocyclo­propane-1-carboxylic acid (ACC) deaminase due to the increased reactivity of its cyclopropyl functionality. It is shown that DFACC is unstable under near-physiological conditions where it primarily decomposes via specific-base catalysis to 3-fluoro-2-oxobut-3-enoic acid with a rate constant of 0.18±0.01 min–1. Upon incubation with ACC deaminase, DFACC is found to be a slow-dissociating inhibitor of ACC deaminase with submicromolar affinity.