Two-dimensional NMR studies of the antimicrobial peptide NP-5.
Nearly complete proton resonance assignment of the rabbit antimicrobial peptide NP-5 has been made from two-dimensional NMR data taken at a single temperature. The assignment procedure involved acquisition of phase-sensitive double-quantum-filtered correlation spectra, relayed coherence-transfer spectra, total correlation (homonuclear Hartmann-Hahn) spectra, double- and triple-quantum spectra, and nuclear Overhauser effect spectra. The combination of these complementary experiments simplified and accelerated resonance assignment of the peptide. Individual assignments were made at 20 degrees C for all amide and C alpha protons in the peptide, and for all nonlabile side-chain protons on 26 of the 33 amino acid residues in NP-5. Analysis of the proton-proton nuclear Overhauser effect connectivities, the slowly exchanging amide protons, and the proton chemical shifts in NP-5 indicates that the peptide has a stable, ordered structure in solution. These data also indicate that residues 19-29 in NP-5 are involved in an antiparallel beta-sheet that has a hairpin conformation.
Bach
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Department of Chemistry, Rutgers, State University of New Jersey, New Brunswick 08903.
Selsted
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Pardi
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D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D011487:Protein Conformation; D011506:Proteins / Q000302:isolation & purification; D011817:Rabbits
D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D011506:Proteins