CRYSTAL STRUCTURES OF VANCOMYCIN RELATED GLYCOPEPTIDE ANTIBIOTICS. Martina Schaefer, Thomas R. Schneider, George M. Sheldrick, Universität Göttingen, Germany

Glycopeptide antibiotics related to vancomycin have been of special clinical interest since 1956 when vancomycin itself was first discovered. Vancomycin is often the last hope in the treatment of infections caused by bacteria that have been developed resistance to other antibiotics, but unfortunately cases of vancomycin resistance are not unknown.

We direct our attention to these glycopeptide antibiotics for two reasons:

- With around 400 peptide atoms and 40-50% solvent content per asymetric unit crystals of glycopetide antibiotics have comparable diffraction properties to rubrodoxin, crambin and other small proteins. They should be good test structures for new ab initio approaches for the solution of the phase problem.

- With atomic resolution data (collected at EMBL-Hamburg with Synchrotron radiation) it is possible to obtain detailed structural information, for example in the region of the postulated binding pocket.

We will present new crystal structures of vancomycin related glycopeptide antibiotics that provide interesting details of the solvent structure, in particular in the region of the binding pocket.