Abstract:
:Prion proteins (PrP) are the infectious agent in transmissible spongiform encephalopathies (i.e., mad cow disease). To be infectious, prion proteins must undergo a conformational change involving a decrease in α-helical content along with an increase in β-strand content. This conformational change was evaluated by means of elastic normal modes. Elastic normal modes show a diminution of two α-helices by one and two residues, as well as an extension of two β-strands by three residues each, which could instigate the conformational change. The conformational change occurs in a region that is compatible with immunological studies, and it is observed more frequently in mutant prions that are prone to conversion than in wild-type prions because of differences in their starting structures, which are amplified through normal modes. These findings are valuable for our comprehension of the conversion mechanism associated with the conformational change in prion proteins.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Samson AO,Levitt Mdoi
10.1021/bi1010514subject
Has Abstractpub_date
2011-03-29 00:00:00pages
2243-8issue
12eissn
0006-2960issn
1520-4995journal_volume
50pub_type
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