NR AOAK
AU Alonso,D.O.V.; An,C.; Daggett,V.
TI Simulations of biomolecules: Characterization of the early steps in the pH-induced conformational conversion of the hamster, bovine and human forms of the prion protein.
QU Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences 2002 Jun 15; 360(1795): 1165-78
IA http://www.journals.royalsoc.ac.uk/media/m37hullxrl1pd5tpulft/contributions/6/n/m/p/6nmp6m7jmacvm0qj.pdf
PT journal article
AB As computer power increases, so too does the range of interesting biomolecular phenomena and properties that can be simulated. It is now possible to simulate complicated protein conformational changes at ambient or physiological temperatures. In this regard, we are attempting to map the conformational transitions of the normal, cellular prion protein (PrPc) to its infectious scrapie isoform (PrPsc), which causes neurodegenerative diseases in many mammals. These two forms have identical sequences and are conformational isomers, with heightened formation of beta-sheet structure in the scrapie form. Conversion can be triggered by lowering the pH, but thus far it has been impossible to characterize the conformational change at high resolution using experimental methods. Therefore, to investigate the effect of acidic pH on PrP conformation, we have performed molecular-dynamics simulations of hamster, human and bovine forms of the prion protein in water at neutral and low pH. In all cases the core of the protein is well maintained at neutral pH. At low pH, however, the protein is more dynamic, and the sheet-like structure increases both by lengthening of the native beta-sheet and by addition of a portion of the N-terminus to widen the sheet by another 2-3 strands.
MH Animals; Cattle; Comparative Study; *Computer Simulation; Cricetinae; Humans; Hydrogen-Ion Concentration; *Models, Molecular; Nerve Tissue Proteins/chemistry; PrPc Proteins/chemistry; PrPsc Proteins/chemistry; Prions/*chemistry/classification; *Protein Conformation; Protein Denaturation; Protein Folding; Protein Structure, Tertiary; Research Support, U.S. Gov't, P.H.S.; Species Specificity
AD Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195-7610, USA
SP englisch
PO England