Solution structure of moricin, an antibacterial peptide, isolated from the silkworm Bombyx mori

FEBS Letters

Hemmi, Hikaru³  Yamakawa, Minoru²  Hara, Seiichi¹  Ishibashi, Jun² 

[1] Noda Institute for Scientific Research, Noda, Chiba 278-0037, Japan;National Institute of Agrobiological Sciences, 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan;National Food Research Institute, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8642, Japan

关键词: Antibacterial peptide;    Moricin;    Nuclear magnetic resonance;    Solution structure;    Bombyx mori;    CecP;    cecropin P1;    TFE;    2;    2;    2-trifluoroethanol;    HFP;    1;    1;    1;    3;    3;    3-hexafluoroisopropanol;    CD;    circular dichroism;    2D;    two-dimensional;    NMR;    nuclear magnetic resonance;    DQF-COSY;    double-quantum-filtered correlated spectroscopy;    TOCSY;    total correlation spectroscopy;    NOESY;    nuclear Overhauser effect spectroscopy;    RMSD;    root mean square deviation;   

DOI  :  10.1016/S0014-5793(02)02637-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A novel antibacterial peptide, moricin, isolated from the silkworm Bombyx mori, consists of 42 amino acids. It is highly basic and the amino acid sequence has no significant similarity to those of other antibacterial peptides. The 20 structures of moricin in methanol have been determined from two-dimensional ¹H-nuclear magnetic resonance spectroscopic data. The solution structure reveals an unique structure comprising of a long α-helix containing eight turns along nearly the full length of the peptide except for four N-terminal residues and six C-terminal residues. The electrostatic surface map shows that the N-terminal segment of the α-helix, residues 5–22, is an amphipathic α-helix with a clear separation of hydrophobic and hydrophilic faces, and that the C-terminal segment of the α-helix, residues 23–36, is a hydrophobic α-helix except for the negatively charged surface at the position of Asp30. The results suggest that the amphipathic N-terminal segment of the α-helix is mainly responsible for the increase in permeability of the membrane to kill the bacteria.

【 授权许可】

Unknown