Structural and dynamic studies of two antigenic loops from haemagglutinin: a relaxation matrix approach.
We have investigated the dynamics and structural behaviour of two antigenic peptides using 1H NMR. The two cyclic peptides mimic the antigenic site A of influenza haemagglutinin protein; they only differ in the way they were cyclized and in the size of their respective linkers. Homonuclear relaxation parameters extracted from a complete NOE matrix were interpreted in terms of local dynamics. A set of distance constraints was deduced from these parameters which allowed 3D models to be constructed using distance geometry. NOE back-calculation was used to check the validity of the final models. Strong variations of internal motion amplitude have been found in both peptides along their backbone. Motions with high amplitudes have been localized in the Gly-Pro-Gly sequence which forms a beta-turn in both structures.
Kieffer
B
B
IBMC du CNRS, Strasbourg, France.
Koehl
P
P
Plaue
S
S
Lefèvre
J F
JF
D000595:Amino Acid Sequence; D000939:Epitopes / Q000737:chemistry*; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008433:Mathematics; D008958:Models, Molecular; D008962:Models, Theoretical; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry*; D010456:Peptides, Cyclic / Q000138:chemical synthesis / Q000737:chemistry*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D014759:Viral Envelope Proteins / Q000737:chemistry
D000939:Epitopes; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006389:Hemagglutinins, Viral; D009842:Oligopeptides; D010456:Peptides, Cyclic; D014759:Viral Envelope Proteins