Document Detail


Seeding-dependent propagation and maturation of beta2-microglobulin amyloid fibrils under high pressure.
MedLine Citation:
PMID:  16697008     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
High hydrostatic pressure reversibly transforms the amyloid fibrils of beta2-microglobulin (beta2-m) into a more tightly packed, reorganized structure, which has provided insight into the polymorphic properties of amyloid fibrils. Here, to further investigate the molecular mechanism that controls fibril structure, seed-dependent fibril growth from an acid-unfolded monomeric form under high pressure was studied. At all pressures up to 400 MPa, the fibril growth could be approximated by a single-exponential kinetics, although pressure above 300 MPa decreased the growth rate significantly. The fibrils formed at high pressure were similar to the reorganized fibrils formed initially at ambient pressure and then pressurized, suggesting that the reorganized fibrils were formed directly at high pressure. A systematic investigation of the extension rate under various pressures indicated that the activation free energies for the original and reorganized fibrils are significantly different, suggesting that different amino acid contacts are involved in these two types of fibrils. On the other hand, for the seed-dependent extension reactions of both types of fibrils, the activation volume was much smaller than the change in reaction volume, implying that only small numbers of side-chain interactions are achieved in the transition state. Importantly, we observed a marked acceleration of fibril growth, i.e., maturation, on repeated self-seeding above 300 MPa, revealing the coexistence of another type of fibril with a similar structure but with an increased growth-rate under high pressure.
Authors:
Eri Chatani; Hironobu Naiki; Yuji Goto
Related Documents :
16851178 - N-heptane under pressure: structure and dynamics from molecular simulations.
19874878 - Separation of major catechins from green tea by ultrahigh pressure extraction.
18284998 - Temperature and pressure dependence of dielectric properties of ceramic pb(fe(1/2)ta(1/...
19445828 - Effect of high-pressure homogenisation on rheological properties of rennet-induced skim...
11673348 - Ventricular dysfunction after cardioplegic arrest is improved after myocardial gene tra...
15526988 - Prenatal dietary docosahexaenoic acid supplementation in combination with protein restr...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2006-04-25
Journal Detail:
Title:  Journal of molecular biology     Volume:  359     ISSN:  0022-2836     ISO Abbreviation:  J. Mol. Biol.     Publication Date:  2006 Jun 
Date Detail:
Created Date:  2006-06-12     Completed Date:  2006-08-10     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  2985088R     Medline TA:  J Mol Biol     Country:  England    
Other Details:
Languages:  eng     Pagination:  1086-96     Citation Subset:  IM    
Affiliation:
Institute for Protein Research, Osaka University and CREST, Japan Science and Technology Agency, Suita, Osaka 565-0871, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Amyloid / chemistry,  metabolism*
Humans
Kinetics
Pressure
beta 2-Microglobulin / chemistry*,  metabolism*
Chemical
Reg. No./Substance:
0/Amyloid; 0/beta 2-Microglobulin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  From the similarity analysis of protein cavities to the functional classification of protein familie...
Next Document:  The 2.1A crystal structure of copGFP, a representative member of the copepod clade within the green ...