Download MendeleyStructure determination of human and murine beta-defensins reveals structural conservation in the absence of significant sequence similarity.
Bauer, F., Schweimer, K., Kluver, E., Conejo-Garcia, J.R., Forssmann, W.G., Rosch, P., Adermann, K., Sticht, H.(2001) Protein Sci 10: 2470-2479
- PubMed: 11714914
- DOI: https://doi.org/10.1110/ps.24401
- Primary Citation of Related Structures:
1E4Q, 1E4R, 1E4S, 1E4T - PubMed Abstract:
Defensins are cationic and cysteine-rich peptides that play a crucial role in the host defense against microorganisms of many organisms by their capability to permeabilize bacterial membranes. The low sequence similarity among the members of the large mammalian beta-defensin family suggests that their antimicrobial activity is largely independent of their primary structure. To investigate to what extent these defensins share a similar fold, the structures of the two human beta-defensins, hBD-1 and hBD-2, as well as those of two novel murine defensins, termed mBD-7 and mBD-8, were determined by nuclear magnetic resonance spectroscopy. All four defensins investigated share a striking similarity on the level of secondary and tertiary structure including the lack of a distinct hydrophobic core, suggesting that the fold is mainly stabilized by the presence of three disulfide bonds. In addition to the overall shape of the molecules, the ratio of solvent-exposed polar and hydrophobic side chains is also very similar among the four defensins investigated. It is significant that beta-defensins do not exhibit a common pattern of charged and hydrophobic residues on the protein surface and that the beta-defensin-specific fold appears to accommodate a wide range of different amino acids at most sequence positions. In addition to the implications for the mode of biological defensin actions, these findings are of particular interest because beta-defensins have been suggested as lead compounds for the development of novel peptide antibiotics for the therapy of infectious diseases.
Organizational Affiliation:
Lehrstuhl für Biopolymere, Universität Bayreuth, D-95440 Bayreuth, Germany.
