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Hu KN, McGlinchey RP, Wickner RB, Tycko R. Segmental polymorphism in a functional amyloid. Biophys J 2011; 101:2242-50. [PMID: 22067164 DOI: 10.1016/j.bpj.2011.09.051] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 09/22/2011] [Accepted: 09/29/2011] [Indexed: 11/25/2022] Open
Abstract
Although amyloid fibrils are generally considered to be causative or contributing agents in amyloid diseases, several amyloid fibrils are also believed to have biological functions. Among these are fibrils formed by Pmel17 within melanosomes, which act as a template for melanin deposition. We use solid-state NMR to show that the molecular structures of fibrils formed by the 130-residue pseudo-repeat domain Pmel17:RPT are polymorphic even within the biologically relevant pH range. Thus, biological function in amyloid fibrils does not necessarily imply a unique molecular structure. Solid-state NMR spectra of three Pmel17:RPT polymorphs show that in all cases, only a subset (~30%) of the full amino acid sequence contributes to the immobilized fibril core. Although the repetitive nature of the sequence and incomplete spectral resolution prevent the determination of unique chemical shift assignments from two- and three-dimensional solid-state NMR spectra, we use a Monte Carlo assignment algorithm to identify protein segments that are present in or absent from the fibril core. The results show that the identity of the core-forming segments varies from one polymorph to another, a phenomenon known as segmental polymorphism.
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Affiliation(s)
- Kan-Nian Hu
- Laboratory of Chemical Physics, National Institute of Diabetes Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
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Gochin M, Pines A, Rosen M, Rucker S, Schmidt C. Two-dimensional N.M.R. studies of flexible molecules in liquid crystals: orientational order and conformational probabilities ofn-hexane. Mol Phys 2006. [DOI: 10.1080/00268979000100501] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- M. Gochin
- a Materials and Chemical Sciences Division , Lawrence Berkeley Laboratory , 1 Cyclotron Road, Berkeley , California , 94720 , U.S.A
- b Department of Chemistry , University of California , Berkeley , California , 94720 , U.S.A
- c Department of Pharmaceutical Chemistry , University of California , San Francisco , California , 94143 , U.S.A
| | - A. Pines
- a Materials and Chemical Sciences Division , Lawrence Berkeley Laboratory , 1 Cyclotron Road, Berkeley , California , 94720 , U.S.A
- b Department of Chemistry , University of California , Berkeley , California , 94720 , U.S.A
| | - M.E. Rosen
- a Materials and Chemical Sciences Division , Lawrence Berkeley Laboratory , 1 Cyclotron Road, Berkeley , California , 94720 , U.S.A
- b Department of Chemistry , University of California , Berkeley , California , 94720 , U.S.A
| | - S.P. Rucker
- a Materials and Chemical Sciences Division , Lawrence Berkeley Laboratory , 1 Cyclotron Road, Berkeley , California , 94720 , U.S.A
- b Department of Chemistry , University of California , Berkeley , California , 94720 , U.S.A
| | - C. Schmidt
- a Materials and Chemical Sciences Division , Lawrence Berkeley Laboratory , 1 Cyclotron Road, Berkeley , California , 94720 , U.S.A
- b Department of Chemistry , University of California , Berkeley , California , 94720 , U.S.A
- d Institut für Makromolekulare Chemie, Universität Freiburg , Stefan-Meier-Strasse 31, D-7800 , Freiburg , F.R. Germany
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Photinos D, Poliks BJ, Samulski E, Terzis A, Toriumi H. n-Hexane proton dipolar couplings and the rotational isomeric state approximation. Mol Phys 2006. [DOI: 10.1080/00268979100100261] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- D.J. Photinos
- a Department of Chemistry , University of North Carolina , Chapel Hill , North Carolina , 27599-3290 , U.S.A
- b Department of Physics , University of Patras , Patras , 26110 , Greece
| | - B. Janik Poliks
- a Department of Chemistry , University of North Carolina , Chapel Hill , North Carolina , 27599-3290 , U.S.A
- c Institute of Nuclear Physics , Krakow , Poland
| | - E.T. Samulski
- a Department of Chemistry , University of North Carolina , Chapel Hill , North Carolina , 27599-3290 , U.S.A
| | - A.F. Terzis
- a Department of Chemistry , University of North Carolina , Chapel Hill , North Carolina , 27599-3290 , U.S.A
- b Department of Physics , University of Patras , Patras , 26110 , Greece
| | - H. Toriumi
- a Department of Chemistry , University of North Carolina , Chapel Hill , North Carolina , 27599-3290 , U.S.A
- d Department of Chemistry , University of Tokyo , Komaba, Meguro, Tokyo , 153 , Japan
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Tan C, Fung BM. Determination of Bond Distances and Bond Angles in a Liquid Crystal with Hydrogen Bonding. J Phys Chem B 2003. [DOI: 10.1021/jp027738i] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Chibing Tan
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma, 73019-3051
| | - B. M. Fung
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma, 73019-3051
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Gochin M, Hugi-Cleary D, Zimmermann H, Pines A. Two-dimensional multiple quantum N.M.R. of isotopic mixtures in liquid crystals. Mol Phys 1987. [DOI: 10.1080/00268978700100151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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