NMR studies on the flexibility of the poliovirus C3 linear epitope inserted into different sites of the maltose-binding protein.
A set of permissive positions that tolerate insertions/deletions without major deleterious consequences for the binding activity of the protein was previously identified in the maltose-binding protein. The C3 epitope from poliovirus VP1 protein (93DNPASTTNKDK103) was inserted into eight of these positions and two nonpermissive control sites. NMR studies were performed on the MalE protein, the insertion/deletion mutants, and the C3MalE hybrids to selectively determine the flexible regions in these proteins. Comparison of the C3 epitope mobility in the different hybrid proteins indicates that, whatever its insertion site and independently from the specific sequences of its linkers, the epitope is mostly flexible. The vector protein was shown to unfold partially only in the two C3MalE hybrids that correspond to nonpermissive positions. For one of them (insertion at site 339), both sides of the insert are flexible, and at most one side for all the other hybrids. This result correlates with the antigenicity data on the inserted epitope (Martineau, P., Leclerc, C., and Hofnung, M. (1997) Mol. Immunol, in press.
Lecroisey
A
A
Laboratoire de Résonance Magnétique Nucléaire, CNRS URA 1129, Paris,France. alecrois@pasteur.fr
Martineau
P
P
Hofnung
M
M
Delepierre
M
M
D000595:Amino Acid Sequence; D000956:Antigens, Viral / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry*; D002213:Capsid / Q000737:chemistry*; D036022:Capsid Proteins; D002352:Carrier Proteins / Q000737:chemistry; D000939:Epitopes; D009682:Magnetic Resonance Spectroscopy; D058619:Maltose-Binding Proteins; D008969:Molecular Sequence Data; D009038:Motion; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry*; D013329:Structure-Activity Relationship
D000956:Antigens, Viral; D001426:Bacterial Proteins; D036022:Capsid Proteins; D002352:Carrier Proteins; D000939:Epitopes; D058619:Maltose-Binding Proteins; D011993:Recombinant Fusion Proteins; C442540:VP1 protein, Poliovirus