PDBsum entry: 1zue

Toxin

PDB id: 1zue

Contents

Protein chain

42 a.a.

PDB id:

1zue

Name:

Toxin

Title:

Revised solution structure of dlp-2

Structure:

Defensin-like peptide 2/4. Chain: a. Synonym: dlp-2. Engineered: yes

Source:

Synthetic: yes. Other_details: chemically synthesized

NMR struc:

20 models

Authors:

A.M.Torres,C.Tsampazi,D.P.Geraghty,P.S.Bansal,P.F.Alewood, P.W.Kuchel

Key ref:

A.M.Torres et al. (2005). D-amino acid residue in a defensin-like peptide from platypus venom: effect on structure and chromatographic properties. Biochem J, 391, 215-220. PubMed id: 16033333 Ref: Full text

Date:

30-May-05 Release date: 02-Aug-05

Protein chain

P82140  (DLP2_ORNAN) -  Defensin-like peptide 2/4

Seq: 66 a.a.

Struc: 42 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

 Gene Ontology (GO) functional annotation 

• Cellular component: extracellular region (1 term)
• Biological process: pathogenesis (1 term)
• Biochemical function: molecular_function (1 term)

Full text	Biochem J 391:215-220 (2005)
PubMed id: 16033333

D-amino acid residue in a defensin-like peptide from platypus venom: effect on structure and chromatographic properties.

A.M.Torres, C.Tsampazi, D.P.Geraghty, P.S.Bansal, P.F.Alewood, P.W.Kuchel.

ABSTRACT

The recent discovery that the natriuretic peptide OvCNPb (Ornithorhynchus venom C-type natriuretic peptide B) from platypus (Ornithorynchus anatinus) venom contains a D-amino acid residue suggested that other D-amino-acid-containing peptides might be present in the venom. In the present study, we show that DLP-2 (defensin-like peptide-2), a 42-amino-acid residue polypeptide in the platypus venom, also contains a D-amino acid residue, D-methionine, at position 2, while DLP-4, which has an identical amino acid sequence, has all amino acids in the L-form. These findings were supported further by the detection of isomerase activity in the platypus gland venom extract that converts DLP-4 into DLP-2. In the light of this new information, the tertiary structure of DLP-2 was recalculated using a new structural template with D-Met2. The structure of DLP-4 was also determined in order to evaluate the effect of a D-amino acid at position 2 on the structure and possibly to explain the large retention time difference observed for the two molecules in reverse-phase HPLC. The solution structures of the DLP-2 and DLP-4 are very similar to each other and to the earlier reported structure of DLP-2, which assumed that all amino acids were in the L-form. Our results suggest that the incorporation of the D-amino acid at position 2 has minimal effect on the overall fold in solution.