The Structure of FemXWv in Complex with a Peptidyl-RNA Conjugate: Mechanism of Aminoacyl Transfer from Ala-tRNAAla to Peptidoglycan Precursors

M. Fonvielle, I. Li de La Sierra-Gallay, A. H. El-Sagheer, M. Lecerf, D. Patin, D. Mellal, C. Mayer, D. Blanot, N. Gale, T. Brown, H. van Tilbeurgh, M. Ethève-Quelquejeu and M. Arthur. Angew. Chem. Int. Ed. 52 (28), 7278-7281, 2013.


To gain insight into the catalytic mechanism of non-ribosomal amino acid transferases, peptidyl-RNA conjugates were synthesized for co-crystallization with FemXWv of Weissella viridescens, which transfers l-Ala from Ala-tRNAAla to the peptidoglycan precursor UDP-MurNAc-pentapeptide. The structure of the resulting complex and mutational studies revealed the mechanism by which FemXWv binds its substrates for substrate-assisted catalysis and stabilization of the tetrahedral intermediate.