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1mr4
From Proteopedia
| 1mr4, 20 NMR models () | |||||||
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| Domains: | Gamma-thionin | ||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Contents |
Solution Structure of NaD1 from Nicotiana alata
NMR spectroscopy and simulated annealing calculations have been used to determine the three-dimensional structure of NaD1, a novel antifungal and insecticidal protein isolated from the flowers of Nicotiana alata. NaD1 is a basic, cysteine-rich protein of 47 residues and is the first example of a plant defensin from flowers to be characterized structurally. Its three-dimensional structure consists of an alpha-helix and a triple-stranded antiparallel beta-sheet that are stabilized by four intramolecular disulfide bonds. NaD1 features all the characteristics of the cysteine-stabilized alphabeta motif that has been described for a variety of proteins of differing functions ranging from antibacterial insect defensins and ion channel-perturbing scorpion toxins to an elicitor of the sweet taste response. The protein is biologically active against insect pests, which makes it a potential candidate for use in crop protection. NaD1 shares 31% sequence identity with alfAFP, an antifungal protein from alfalfa that confers resistance to a fungal pathogen in transgenic potatoes. The structure of NaD1 was used to obtain a homology model of alfAFP, since NaD1 has the highest level of sequence identity with alfAFP of any structurally characterized antifungal defensin. The structures of NaD1 and alfAFP were used in conjunction with structure-activity data for the radish defensin Rs-AFP2 to provide an insight into structure-function relationships. In particular, a putative effector site was identified in the structure of NaD1 and in the corresponding homology model of alfAFP.
The three-dimensional solution structure of NaD1, a new floral defensin from Nicotiana alata and its application to a homology model of the crop defense protein alfAFP., Lay FT, Schirra HJ, Scanlon MJ, Anderson MA, Craik DJ, J Mol Biol. 2003 Jan 3;325(1):175-88. PMID:12473460
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
About this Structure
1MR4 is a Single protein structure of sequence from Nicotiana tabacum. Full experimental information is available from OCA.
Reference
The three-dimensional solution structure of NaD1, a new floral defensin from Nicotiana alata and its application to a homology model of the crop defense protein alfAFP., Lay FT, Schirra HJ, Scanlon MJ, Anderson MA, Craik DJ, J Mol Biol. 2003 Jan 3;325(1):175-88. PMID:12473460
Page seeded by OCA on Mon Jul 28 18:29:55 2008
Related References
The plant defensin, NaD1, enters the cytoplasm of Fusarium oxysporum hyphae., van der Weerden NL, Lay FT, Anderson MA, J Biol Chem. 2008 May 23;283(21):14445-52. PMID:18339623
Defensins - Components of the innate immune system in plants., Lay FT, Anderson MA, Curr Protein Pept Sci. 2005 Feb;6(1):85-101. PMID: 15638771
Structure of Petunia hybrida defensin 1, a novel plant defensin with five disulfide bonds., Janssen BJ, Schirra HJ, Lay FT, Anderson MA, Craik DJ. Biochemistry. 2003 Jul 15;42(27):8214-22. PMID:12846570
Isolation and properties of floral defensins from ornamental tobacco and petunia. Lay FT, Brugliera F, Anderson MA. Plant Physiol. 2003 Mar;131(3):1283-93. PMID:12644678
