Speaker
Dr
Arefeh Seyedarabi
(Institute of Biochemistry and Biophysics, University of Tehran)
Description
The structure of protein molecules (either in their apo or halo forms) can be determined through three different techniques: (1) X-ray crystallography, (2) NMR and (3) Electron microscopy, with each technique having its own limitations. However, the most widely used method for the determination of protein structure as clearly revealed from the Protein Data Bank statistics to date is X-ray crystallography with 105316 pdb entries compared to NMR with 11377 pdb entries and Electron Microscopy with only 1001 pdb entries. This shows the highly significant (almost 90%) use of X-ray crystallography to reveal protein structure to answer many undoubtedly important questions related to the function of proteins in living organisms. X-ray crystallography of protein molecules, or better said 'macromolecular crystallography' is hence an important and invaluable tool for the determination of protein structures at the atomic detail, giving a wealth of knowledge about the protein bio-molecule. Macromolecular crystallography can be used to provide precious information and covers studies in many research fields including medicine, pharmacy, agriculture and even marine biology. With this information in mind, the work presented here covers the structures obtained and functions studied of proteins involved in (a) bacterial diseases both in human and plants, including results on the IpaH9.8 E3 Ubiquitin ligase from Shigella flexneri and Pectate lyase from Bacillus subtilis, (b) vitamin B12 biosynthesis essential for human diet, including results on the structure, sequence and evolution of methyltransferases fundamental in the decoration of a tetrapyrrole to arrive at the final product and nature's most complex small molecule, Vitamin B12, (c) Angiogenesis and vasculogenesis, describing a novel strategy to enable the over-production of soluble human VEGF protein in the conveniently used E. coli and (d) a recent project native to Iran on two Caspian Sea sturgeon Hemoglobin (fish belonging to the family Acipenseridae) revealing novel sequence and structure information. The latter project provides an example of the use of macromolecluar crystallography to advance many essential projects on-hand and of course, the development of ILSF can undeniably provide a bright future for macromolecular crystallography in Iran.
Author
Dr
Arefeh Seyedarabi
(Institute of Biochemistry and Biophysics, University of Tehran)
