Secondary structure of an antibacterial peptide Abp3 studied by two-dimensional proton-NMR.
An antibacterial peptide Abp3, an analogue of cecropin B, was investigated by two-dimensional proton-NMR at pH 5.0 in aqueous solution with 15% (v/v) hexafluoroisopropanol. The peptide, which consists of 35 amino acids, was synthesized chemically. Most resonances of the main-chain and side-chain protons were assigned. Several medium range NOE connectivities were observed, showing two separate alpha-helices with one amphiphilic in N-terminal domain (residues 5-21) and the other hydrophobic in C-terminal domain (residues 25-35) and a hinge region between them. The J coupling constants and the chemical shifts in these sections also supported the conclusion.
Xia
W
W
Department of Biology, University of Science and Technology of China, Hefei, Anhui, China.
Liu
Q
Q
Wu
J
J
Xia
Y
Y
Shi
Y
Y
Qu
X
X
D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry*; D019476:Insect Proteins / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010455:Peptides; D017433:Protein Structure, Secondary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D000900:Anti-Bacterial Agents; D019476:Insect Proteins; D010455:Peptides; C031162:cecropin B protein, Insecta