Three-dimensional solution structure of lactoferricin B, an antimicrobial peptide derived from bovine lactoferrin

Biochemistry. 1998 Mar 24;37(12):4288-98. doi: 10.1021/bi972323m.


The solution structure of bovine lactoferricin (LfcinB) has been determined using 2D 1H NMR spectroscopy. LfcinB is a 25-residue antimicrobial peptide released by pepsin cleavage of lactoferrin, an 80 kDa iron-binding glycoprotein with many immunologically important functions. The NMR structure of LfcinB reveals a somewhat distorted antiparallel beta-sheet. This contrasts with the X-ray structure of bovine lactoferrin, in which residues 1-13 (of LfcinB) form an alpha-helix. Hence, this region of lactoferricin B appears able to adopt a helical or sheetlike conformation, similar to what has been proposed for the amyloidogenic prion proteins and Alzheimer's beta-peptides. LfcinB has an extended hydrophobic surface comprised of residues Phe1, Cys3, Trp6, Trp8, Pro16, Ile18, and Cys20. The side chains of these residues are well-defined in the NMR structure. Many hydrophilic and positively charged residues surround the hydrophobic surface, giving LfcinB an amphipathic character. LfcinB bears numerous similarities to a vast number of cationic peptides which exert their antimicrobial activities through membrane disruption. The structures of many of these peptides have been well characterized, and models of their membrane-permeabilizing mechanisms have been proposed. The NMR solution structure of LfcinB may be more relevant to membrane interaction than that suggested by the X-ray structure of intact lactoferrin. Based on the solution structure, it is now possible to propose potential mechanisms for the antimicrobial action of LfcinB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Anti-Bacterial Agents / chemistry*
  • Anti-Infective Agents / chemistry*
  • Cattle
  • Crystallography, X-Ray
  • Lactoferrin / analogs & derivatives*
  • Lactoferrin / chemistry
  • Models, Molecular
  • Molecular Sequence Data
  • Peptides / chemistry*
  • Protein Structure, Secondary
  • Protons
  • Solutions


  • Anti-Bacterial Agents
  • Anti-Infective Agents
  • Peptides
  • Protons
  • Solutions
  • lactoferricin B
  • Lactoferrin