Abstract
The structure of a novel plant defensin isolated from the flowers of Petunia hybrida has been determined by (1)H NMR spectroscopy. P. hybrida defensin 1 (PhD1) is a basic, cysteine-rich, antifungal protein of 47 residues and is the first example of a new subclass of plant defensins with five disulfide bonds whose structure has been determined. PhD1 has the fold of the cysteine-stabilized alphabeta motif, consisting of an alpha-helix and a triple-stranded antiparallel beta-sheet, except that it contains a fifth disulfide bond from the first loop to the alpha-helix. The additional disulfide bond is accommodated in PhD1 without any alteration of its tertiary structure with respect to other plant defensins. Comparison of its structure with those of classic, four-disulfide defensins has allowed us to identify a previously unrecognized hydrogen bond network that is integral to structure stabilization in the family.
| Original language | English |
|---|---|
| Pages (from-to) | 8214-22 |
| Number of pages | 9 |
| Journal | Biochemistry |
| Volume | 42 |
| Issue number | 27 |
| DOIs | |
| Publication status | Published - 15 Jul 2003 |
| Externally published | Yes |
Keywords
- Amino Acid Sequence
- Defensins/chemistry
- Disulfides/chemistry
- Hydrogen Bonding
- Molecular Sequence Data
- Petunia/chemistry
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Static Electricity