Dr. Jonathan Trent, Ames Research Center, NASA, USA
|Date||Mon 15 May|
|Time||11:15 — 12:00|
|Location||AUD I (1514-213), Department of Chemistry, Langelandsgade 140, 8000 Aarhus C|
Christian Anfinsen shared the Nobel Prize for Chemistry in 1972 for research that demonstrated all the information needed for the protein, ribonuclease, to fold into its functional form was contained within its amino acid sequence. In other words, cells do not need protein-folding templates to make functional proteins from the string of amino acids synthesized by their ribosomes. Anfinsen's insight however, was based on experiments using pure protein in dilute solutions, which begged the fundamental unanswered question: How do proteins fold inside the living cell, which is filled with high concentrations of biomolecules? Current theories about in vivo protein folding suggest that there are proteins in cells, called “molecular chaperones,” that assist in the folding process that some of the heat shock proteins (HSPs) are functionally molecular chaperones. The HSP role was based on what was assumed to happen to cells at high temperatures and on observations of acquired thermotolerance.
We will investigate the molecular chaperone theory based on research on heat shock and acquired thermotolerance in the thermo-acidophile, Sulfolobus shibatae—an archaeon living in near-boiling sulfuric acid. While this research initially provided critical support for the molecular chaperone theory (1), it later showed the theory is misleading (2). We will consider an alternative theory for protein folding in vivo called "sensitive chaos."
(1) Trent, J.D., E. Nimmesgern, J. Wall, F.-U. Hartl, and A. Horwich. 1991. A chaperone from a thermophilic archaebacterium is related to the eukaryotic protein, t-complex polypeptide 1. Nature, 354(6353): 490-493.
(2) Trent, Jonathan D., Hiromi Kagawa, Chad Paavola, R. Andrew McMillan, Jeanie Howard, Linda Jahnke, Colleen Lavin, Tsegereda Embaye, and Christopher Henze. 2003. Intracelluar localization of a group II chaperonin indicates a membrane-related function. Proceedings of the National Academy of Sciences, USA, 100: 15589-15594.
Biography: Jonathan Trent
After receiving a PhD in Biological Oceanography from Scripps Institution of Oceanography, Dr. Trent spent six years in Europe at the Max Planck Institute for Biochemistry in Germany, the University of Copenhagen in Denmark, and the University of Paris at Orsay in France. He returned to the USA to work at the Boyer Center for Molecular Medicine at Yale Medical School for two years before establishing a biotechnology group at Argonne National Laboratory.
In 1998 he moved to NASA Ames Research Center where he conducted research in Astrobiology, Protein Nanotechnology, and most recently a life support system for Spaceship Earth called OMEGA. In addition to working at NASA, he is an Adjunct Professor in the Dept. of Biomolecular Engineering at UCSC, an Adjunct Professor in the Dept of Biotechnology and Life Science at Tokyo University of Agriculture and Technology, and he is a Fellow of the California Academy of Sciences.
Host: Director & Professor Jørgen Kjems, Interdisciplinary Nanoscience Center