Actins/chemistry; Amino Acid Sequence; Calcium-Binding Proteins/chemistry; Carboxylic Acids; Carrier Proteins/chemistry; Circular Dichroism; Computer Simulation; Magnetic Resonance Spectroscopy; Microfilament Proteins/chemistry; Models, Molecular; Molecular Sequence Data; Protein Conformation; Protein Structure, Secondary; Temperature
Abstract :
[en] The solution structure of a synthetic 22-amino acid peptide (P1) corresponding to the extreme C-terminal end and one of the F-actin binding sites of villin has been determined by 1H NMR and CD spectroscopy. The structure of this peptide was compared to that of a peptide in which lysine to glutamic acid substitutions were introduced at positions 17 and 19 (P11), abolishing F-actin binding. Both peptides are largely unstructured in aqueous solution. Changes observed in the NMR and CD spectra of both peptides are consistent with alpha-helix formation in trifluoroethanol/water mixtures. A set of 189 interproton distances derived from nuclear Overhauser enhancement (NOE) measurements, 17 phi-angle constraints obtained from 3JNH alpha coupling constants, as well as about 10 N ... O distance restraints deduced from amide proton exchange kinetics with deuterium, were used for the structure determination. The three-dimensional structure of P1 and P11 is characterized by two helical regions, one extending from residues 2 to 5 and a second covering residues 7 to 17. The central fragment, ranging from Leu-7 to Leu-15, is more stable. The C-terminal residues are less structured, particularly within peptide P11. The significance of these structural results is discussed in relation to the biological activity of villin.
Disciplines :
Biochemistry, biophysics & molecular biology
Author, co-author :
Simenel, C.
Rose, T.
Goethals, M.
Vandekerckhove, J.
Friederich, Evelyne ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Life Science Research Unit
Louvard, D.
Delepierre, M.
Language :
English
Title :
Conformational behaviour of a synthetic peptide of the C-terminus of villin that interacts with actin: an NMR, CD and stimulated annealing study.
Publication date :
1995
Journal title :
International Journal of Peptide and Protein Research