Crystallography, molecular modeling and planning of substances of biological interest II

Abstract

This project was the key for the complete establishment of the first laboratory dedicated to Structural Biology research in Brazil, through the techniques of protein crystallography and molecular modelling. This goal was achieved with excelent results, expanding beyond the original objectives of the project. Several proteins were crystallized and had their three dimensional structure determined locally: glucosamine-6-phosphate deaminase from E.coli, in 5 different crystal structures (T-state, R-state, complexes with allosteric activator, inhibitor, and double mutant Cys-Ser); glyceraldehyde-3-phosphate dehydrogenase from T.cruzi, a important enzyme for the rational design of drugs against Chagas disease, an endemic infectious disease in Brazil; GAPDH from duck muscle; Bothropstoxin I, a K49 phospholipase from the venom of the snake Bothrops jararacussu; bovine carbonic anhydrase; a phospholipase A2 from the venom of Bothrops moojeni; a lectin from the seeds of the leguminous Cratylia mollis. Several other proteins were crystallized and are being studies crystallographycally: lectin KM+ from the seeds of A.integrifolia which induces neutrophil migration; calgranulin C from granulocytes; an alpha-amylase inhibitor from wheat with implications in diagnosis of pancreatic disorders and other forms of hyperamylasemias; a glutamate specific serine protease from B.licheniformis. Several proteins were modelled by homology: Sm14, a highly antigenic protein in Schistossoma mansoni, plant storage proteins a-prolamins from Coix, toxins from scorpion venoms. We have excellent facilities which include an Image Plate detector, several SGI graphics workstations, complete biochemistry and molecular biology facilities for cloning, expression, purification and crystallization and a range of spectroscopic techniques, as Circular Dichroism, Fluorescence, EPR, FTIR. We are involved in the construction of a dedicated protein crystallography beamline at the Brazilian Synchrotron Light Source (LNLS), operational from September/97. The coordinator of the project is an International Research Scholar of the Howard Hughes Medical Institute. (AU)