Effect of analogues of diaminopimelic acid on the meso‐diaminopimelate‐adding enzyme from Escherichia coli

Abstract

Several analogues of diaminopimelic acid (A₂pm) were tested as substrates or inhibitors of the meso-diaminopimelate-adding enzyme from Escherichia coli. They included lanthionine derivatives, a phosphonic analogue, heterocyclic compounds, 3-fluoro-A₂pm, 4-methylene-A₂pm and N-hydroxy-A₂pm. The best substrates were, in decreasing order of specific enzyme activity, (2S,3R,6S)-3-fluoro-A₂pm, meso-lanthionine sulfoxide and N-hydroxy-A₂pm (mixture of stereoisomers). In those cases where all the stereoisomers were available, the specificity could be described as meso ⪢ DD ≈ LL. N-Hydroxy-A₂pm (mixture of stereoisomers) strongly inhibited the addition of radioactive meso-A₂pm to UDP-N-acetylmuramoyl-dipeptide.