Biomaterial Database

Conformational change of a synthetic amyloid analogue des[Ala21,30]A42 upon binding to octyl glucoside micelles. 1992

I Laczkó-Hollósi, and M Hollósi, and V M Lee, and H H Mantsch

Institute of Biophysics, Biological Research Center, Szeged, Hungary.

The secondary structure of a synthetic amyloid fragment des [Ala21,30]A42 was studied by circular dichroism and Fourier transformed infrared spectroscopy. Measurements were performed in trifluoroethanol/water and octyl beta-D-glucopyranoside solutions. The spectra of the peptide in trifluoroethanol indicate a high percentage of alpha-helical structure. However, in octyl glucoside, at and above the critical micelle concentration, the peptide adopts a beta-sheet conformation. Secondary structure analysis yields a predominant (> 70%) beta-sheet content. Our data suggest that the peptide backbone or polar side groups of des[Ala21,30]A42 interact with the sugar-coated surface of micelles, which promotes an alpha to beta conformational transition.

UI	MeSH Term	Description	Entries
D008823	Micelles	Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.	Micelle
D010455	Peptides	Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are considered to be larger versions of peptides that can form into complex structures such as ENZYMES and RECEPTORS.	Peptide,Polypeptide,Polypeptides
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D002942	Circular Dichroism	A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Circular Dichroism, Vibrational,Dichroism, Circular,Vibrational Circular Dichroism
D005960	Glucosides	A GLYCOSIDE that is derived from GLUCOSE.	Glucoside
D013055	Spectrophotometry, Infrared	Spectrophotometry in the infrared region, usually for the purpose of chemical analysis through measurement of absorption spectra associated with rotational and vibrational energy levels of molecules. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	IR Spectra,Infrared Spectrophotometry,IR Spectras,Spectra, IR
D016229	Amyloid beta-Peptides	Peptides generated from AMYLOID BETA-PEPTIDES PRECURSOR. An amyloid fibrillar form of these peptides is the major component of amyloid plaques found in individuals with Alzheimer's disease and in aged individuals with trisomy 21 (DOWN SYNDROME). The peptide is found predominantly in the nervous system, but there have been reports of its presence in non-neural tissue.	Alzheimer beta-Protein,Amyloid Protein A4,Amyloid beta-Peptide,Amyloid beta-Protein,beta Amyloid,beta-Amyloid Protein,Alzheimer's ABP,Alzheimer's Amyloid Fibril Protein,Amyloid AD-AP,Amyloid Fibril Protein, Alzheimer's,Amyloid beta-Proteins,ABP, Alzheimer's,AD-AP, Amyloid,Alzheimer ABP,Alzheimer beta Protein,Alzheimers ABP,Amyloid AD AP,Amyloid beta Peptide,Amyloid beta Peptides,Amyloid beta Protein,Amyloid beta Proteins,Amyloid, beta,Protein A4, Amyloid,Protein, beta-Amyloid,beta Amyloid Protein,beta-Peptide, Amyloid,beta-Peptides, Amyloid,beta-Protein, Alzheimer,beta-Protein, Amyloid,beta-Proteins, Amyloid
D017433	Protein Structure, Secondary	The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to ALPHA-HELICES; BETA-STRANDS (which align to form BETA-SHEETS), or other types of coils. This is the first folding level of protein conformation.	Secondary Protein Structure,Protein Structures, Secondary,Secondary Protein Structures,Structure, Secondary Protein,Structures, Secondary Protein