1d6b: Difference between revisions

Revision as of 13:13, 21 February 2008

SOLUTION STRUCTURE OF DEFENSIN-LIKE PEPTIDE-2 (DLP-2) FROM PLATYPUS VENOM

OverviewOverview

The venom of the male Australian duck-billed platypus contains a family of four polypeptides of appox. 5 kDa, which are referred to as defensin-like peptides (DLPs). They are unique in that their amino acid sequences have no significant similarities to those of any known peptides; however, the tertiary structure of one of them, DLP-1, has recently been shown to be similar to beta-defensin-12 and to the sodium neurotoxin peptide ShI (Stichodactyla helianthus neurotoxin I). Although DLPs are the major peptides in the platypus venom, little is known about their biological roles. In this study, we determined the three-dimensional structure of DLP-2 by NMR spectroscopy, with the aim of gaining insights into the natural function of the DLPs in platypus venom. The DLP-2 structure was found to incorporate a short helix that spans residues 9-12, and an antiparallel beta-sheet defined by residues 15-18 and 37-40. The overall fold and cysteine-pairing pattern of DLP-2 were found to be similar to those of DLP-1, and hence beta-defensin-12; however, the sequence similarities between the three molecules are relatively small. The distinct structural fold of the DLP-1, DLP-2, and beta-defensin-12 is based upon several key residues that include six cysteines. DLP-3 and DLP-4 are also likely to be folded similarly since they have high sequence similarity with DLP-2. The DLPs, and beta-defensin-12 may thus be grouped together into a class of polypeptide molecules which have a common or very similar global fold. The fact that the DLPs did not display antimicrobial, myotoxic, or cell-growth-promoting activities implies that the nature of the side chains in this group of peptides is likely to play an important role in defining the biological function(s).

About this StructureAbout this Structure

1D6B is a Single protein structure of sequence from Ornithorhynchus anatinus. Full crystallographic information is available from OCA.

ReferenceReference

Defensin-like peptide-2 from platypus venom: member of a class of peptides with a distinct structural fold., Torres AM, de Plater GM, Doverskog M, Birinyi-Strachan LC, Nicholson GM, Gallagher CH, Kuchel PW, Biochem J. 2000 Jun 15;348 Pt 3:649-56. PMID:10839998

Page seeded by OCA on Thu Feb 21 12:13:27 2008

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OCA

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-[[Image:1d6b.jpg|left|200px]]<br /><applet load="1d6b" size="450" color="white" frame="true" align="right" spinBox="true"
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 caption="1d6b" />
 '''SOLUTION STRUCTURE OF DEFENSIN-LIKE PEPTIDE-2 (DLP-2) FROM PLATYPUS VENOM'''<br />
 ==Overview==
-The venom of the male Australian duck-billed platypus contains a family of, four polypeptides of appox. 5 kDa, which are referred to as defensin-like, peptides (DLPs). They are unique in that their amino acid sequences have, no significant similarities to those of any known peptides; however, the, tertiary structure of one of them, DLP-1, has recently been shown to be, similar to beta-defensin-12 and to the sodium neurotoxin peptide ShI, (Stichodactyla helianthus neurotoxin I). Although DLPs are the major, peptides in the platypus venom, little is known about their biological, roles. In this study, we determined the three-dimensional structure of, DLP-2 by NMR spectroscopy, with the aim of gaining insights into the, natural function of the DLPs in platypus venom. The DLP-2 structure was, found to incorporate a short helix that spans residues 9-12, and an, antiparallel beta-sheet defined by residues 15-18 and 37-40. The overall, fold and cysteine-pairing pattern of DLP-2 were found to be similar to, those of DLP-1, and hence beta-defensin-12; however, the sequence, similarities between the three molecules are relatively small. The, distinct structural fold of the DLP-1, DLP-2, and beta-defensin-12 is, based upon several key residues that include six cysteines. DLP-3 and, DLP-4 are also likely to be folded similarly since they have high sequence, similarity with DLP-2. The DLPs, and beta-defensin-12 may thus be grouped, together into a class of polypeptide molecules which have a common or very, similar global fold. The fact that the DLPs did not display antimicrobial, myotoxic, or cell-growth-promoting activities implies that the nature of, the side chains in this group of peptides is likely to play an important, role in defining the biological function(s).
+The venom of the male Australian duck-billed platypus contains a family of four polypeptides of appox. 5 kDa, which are referred to as defensin-like peptides (DLPs). They are unique in that their amino acid sequences have no significant similarities to those of any known peptides; however, the tertiary structure of one of them, DLP-1, has recently been shown to be similar to beta-defensin-12 and to the sodium neurotoxin peptide ShI (Stichodactyla helianthus neurotoxin I). Although DLPs are the major peptides in the platypus venom, little is known about their biological roles. In this study, we determined the three-dimensional structure of DLP-2 by NMR spectroscopy, with the aim of gaining insights into the natural function of the DLPs in platypus venom. The DLP-2 structure was found to incorporate a short helix that spans residues 9-12, and an antiparallel beta-sheet defined by residues 15-18 and 37-40. The overall fold and cysteine-pairing pattern of DLP-2 were found to be similar to those of DLP-1, and hence beta-defensin-12; however, the sequence similarities between the three molecules are relatively small. The distinct structural fold of the DLP-1, DLP-2, and beta-defensin-12 is based upon several key residues that include six cysteines. DLP-3 and DLP-4 are also likely to be folded similarly since they have high sequence similarity with DLP-2. The DLPs, and beta-defensin-12 may thus be grouped together into a class of polypeptide molecules which have a common or very similar global fold. The fact that the DLPs did not display antimicrobial, myotoxic, or cell-growth-promoting activities implies that the nature of the side chains in this group of peptides is likely to play an important role in defining the biological function(s).
 ==About this Structure==
-D6B is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Ornithorhynchus_anatinus Ornithorhynchus anatinus]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1D6B OCA].
+D6B is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Ornithorhynchus_anatinus Ornithorhynchus anatinus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1D6B OCA].
 ==Reference==
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 [[Category: Ornithorhynchus anatinus]]
 [[Category: Single protein]]
-[[Category: Birinyi-Strachan, L.C.]]
+[[Category: Birinyi-Strachan, L C.]]
 [[Category: Doverskog, M.]]
-[[Category: Gallagher, C.H.]]
+[[Category: Gallagher, C H.]]
-[[Category: Kuchel, P.W.]]
+[[Category: Kuchel, P W.]]
-[[Category: Nicholson, G.M.]]
+[[Category: Nicholson, G M.]]
-[[Category: Plater, G.M.De.]]
+[[Category: Plater, G M.De.]]
-[[Category: Torres, A.M.]]
+[[Category: Torres, A M.]]
 [[Category: antiparallel beta-sheet]]
 [[Category: helix]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 13:02:13 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:13:27 2008''