Maria Antonietta Vanoni
Dipartimento di Scienze Biomolecolari e Biotecnologie, Universita' degli Studi di Milano, Italy

Understanding the structure-function relations is the main goal of mechanistic enzymologists, forming the basis for the understanding of the variety of biological functions carried out by enzymes, for their engineering for practical purposes, for the design of novel drugs or for metabolic engineering. X-ray crystallography provides high resolution atomic models of enzymes, complementing kinetic and spectroscopic studies in solution. However, the approach requires crystals suitable for X-ray diffraction studies. In several instances crystals of sufficient quality may not be obtained, crystallization may trap inactive protein conformations or just individual components of a multisubunit complex. Furthermore, it is increasingly evident that in several enzymes conformational changes do occur during the catalytic cycle. In these and other cases, alternative approaches must be used to obtain structural information on a given enzymatic system, possibly under conditions that are as close as possible to the physiological ones or, at least, to those of functional (kinetic and spectroscopic) studies.

The lecture will address the current status of our understanding of the structure-function relationships in glutamate synthases (GltS) and, if time allows, glutamyl-tRNA synthetase (GluRS) as gathered from the combined approaches of X-ray crystallography, small-angle X-ray scattering, cryo electron microscopy , atomic force microscopy as well as from kinetic and spectroscopic studies on wild-type and engineered forms of these enzymes.

Date/time: Saturday, 25 October, 9:00