Biomaterial Database

Tertiary peptide bond containing-oligo(Leu)s. Conformational studies in solution of oligo (L-leucine)s with L-proline residue and glycyl-N-(2, 4-dimethoxybenzyl)-L-leucine sequence. 1984

M Narita, and K Ishikawa, and H Nakano, and S Isokawa

In order to elucidate the role of tertiary peptide bonds in the conformational development and solubility improvement of peptides, the conformational properties of oligo(Leu)s with the Pro residue and the Gly-(Dmob)Leu sequence were investigated in solution using i.r. absorption, CD, and molar rotation measurements. The i.r. absorption spectroscopy indicated that the peptides soluble in inert solvents such as CCl4 and toluene had a predominantly beta-sheet structure in these solvents. The conformations of the peptides in CCl4 and toluene were essentially the same as those in a solid state, whereas in THF and in MeOH, the peptides examined were efficiently subjected to solvation, and a randomly coiled structure was predominant. In order to confirm the randomly coiled structure, measurements have been made of the molar rotations of the peptides in a variety of strong proton acceptor and donor solvents. CD measurements are also carried out in MeOH. Through the investigations, it was shown that the protection of peptide bonds and the insertion of the Pro residue had the same effect on conformational and solubilizing behaviors and induced onset of an unordered structure and easy solvation of the peptides in medium and high polarity-solvents.

UI	MeSH Term	Description	Entries
D007202	Indicators and Reagents	Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)	Indicator,Reagent,Reagents,Indicators,Reagents and Indicators
D009842	Oligopeptides	Peptides composed of between two and twelve amino acids.	Oligopeptide
D009905	Optical Rotatory Dispersion	The method of measuring the dispersion of an optically active molecule to determine the relative magnitude of right- or left-handed components and sometimes structural features of the molecule.	Dispersion, Optical Rotatory,Rotatory Dispersion, Optical
D011392	Proline	A non-essential amino acid that is synthesized from GLUTAMIC ACID. It is an essential component of COLLAGEN and is important for proper functioning of joints and tendons.	L-Proline,L Proline
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
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
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
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships