3D STRUCTURE OF THE COMPLEX OF MDL 63,246 WITH THE CELL WALL MODEL PEPTIDE AC-2-LYS-D-ALA-D-ALA

摘要

The complex between the glycopeptide MDL 62,346 and the model cell wall analog Ac-2-Lys-D-Ala-D-Ala was studied by NMR spectroscopy in DMSO solution. A complete assignment of proton and carbon resonances was achieved, and the data were compared with the results observed for the free glycopeptide. NOE buildup rates were determined to calculate interproton distances which were used as constraints to model the 3D structure of the complex. Molecular dynamics simulations were performed in DMSO to gain further insight into the stability of the complex and the dynamical behavior of structural features. The structure of the glycopeptide backbone and the attractive interactions in the intermolecular interface are very well defined. The complex is stabilized by the formation of five intermolecular hydrogen bonds between the glycopeptide and the tripeptide.