Biomaterial Database

Circular dichroism studies on synthetic peptides corresponding to the cleavage site region of precursor proteins. 1987

G L Reddy, and R Nagaraj

The conformations of synthetic peptides which span the region in which the precursor part of proteins (signal sequences) destined for export are cleaved by signal peptidases, were investigated by circular dichroism spectroscopy. Pentapeptides comprising amino acids only from the carboxy-terminus of signal sequences or the amino terminus of the mature protein do not have any preferred conformation in a variety of solvents. Octa- and nonapeptides containing amino acids from the carboxy-terminal protion of signal sequences and the amino-terminus of the mature portions of precursor proteins tend to adopt beta-turn conformations in trifluoroethanol and micelles of sodium dodecylsulphate. Hence, in addition to the distribution of amino acids with small side chains at the carboxy terminus of signal sequences, it is conceivable that signal peptidases also recognize a beta-turn conformation in the cleavage site region of precursor proteins.

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
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
D011498	Protein Precursors		Precursors, Protein
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
D021382	Protein Sorting Signals	Amino acid sequences found in transported proteins that selectively guide the distribution of the proteins to specific cellular compartments.	Leader Signal Peptides,Leader Peptide,Leader Sequences, Peptide,Peptide Leader Sequences,Peptide Signal Sequences,Signal Peptide,Signal Peptides,Signal Sequence, Peptide,Signal Sequences,Signal Sequences, Peptide,Leader Peptides,Leader Sequence, Peptide,Leader Signal Peptide,Peptide Leader Sequence,Peptide Signal Sequence,Peptide, Leader,Peptide, Leader Signal,Peptide, Signal,Peptides, Leader,Peptides, Leader Signal,Peptides, Signal,Protein Sorting Signal,Sequence, Peptide Leader,Sequence, Peptide Signal,Sequence, Signal,Sequences, Peptide Leader,Sequences, Peptide Signal,Sequences, Signal,Signal Peptide, Leader,Signal Peptides, Leader,Signal Sequence,Signal, Protein Sorting,Signals, Protein Sorting,Sorting Signal, Protein,Sorting Signals, Protein