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2dpe
From Proteopedia
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==Overview== | ==Overview== | ||
| - | A 40kDa glycoprotein from dry secretion of sheep is implicated as a | + | A 40kDa glycoprotein from dry secretion of sheep is implicated as a signaling factor and is named as SPS-40. This protein is secreted only during the early phase of involution when the drastic tissue remodeling occurs in the mammary gland. SPS-40 was purified from sheep dry secretions and crystallized using hanging drop vapour diffusion method. The crystals belong to orthorhombic space group P2(1)2(1)2(1) with cell dimensions, a=62.7A, b=66.4A, c=107.5A. The protein was also cloned for the determination of its complete amino acid sequence. The three-dimensional structure of SPS-40 was determined by X-ray crystallographic method at 2.0A resolution. The structure revealed the presence of an N-linked glycan chain at Asn39. The protein adopts a conformation with a classical (beta/alpha)(8)-barrel fold of triosephosphate isomerase (TIM) (residues 1-237 and 310-360) with an insertion of a small (alpha+beta) domain (residues 240-307) similar to that observed in chitinases. However, the Leu substitution for Glu in the consensus catalytic sequence in SPS-40 causes a loss of chitinase activity. Furthermore, the sugar-binding groove in SPS-40 is distorted considerably from the standard chitin-binding site in chitinase enzymes and hence the binding of chitin-like oligosaccharides is considerably hampered. Three surface loops, His188-His197, Phe202-Arg212 and Phe244-Pro260 have exceptionally high values of B-factors (average=70.5A(2)), indicating the presence of a less defined region. |
==About this Structure== | ==About this Structure== | ||
| - | 2DPE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Ovis_aries Ovis aries]. This structure | + | 2DPE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Ovis_aries Ovis aries]. This structure supersedes the now removed PDB entry 1R2V. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2DPE OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Das, U.]] | [[Category: Das, U.]] | ||
| - | [[Category: Ethayathulla, A | + | [[Category: Ethayathulla, A S.]] |
[[Category: Kumar, J.]] | [[Category: Kumar, J.]] | ||
[[Category: Sharma, S.]] | [[Category: Sharma, S.]] | ||
[[Category: Singh, N.]] | [[Category: Singh, N.]] | ||
| - | [[Category: Singh, T | + | [[Category: Singh, T P.]] |
[[Category: Srinivasan, A.]] | [[Category: Srinivasan, A.]] | ||
| - | [[Category: Srivastava, D | + | [[Category: Srivastava, D B.]] |
[[Category: involution]] | [[Category: involution]] | ||
[[Category: mammary gland secretion]] | [[Category: mammary gland secretion]] | ||
[[Category: signaling protein]] | [[Category: signaling protein]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:01:10 2008'' |
Revision as of 15:01, 21 February 2008
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Crystal structure of a secretory 40KDA glycoprotein from sheep at 2.0A resolution
Overview
A 40kDa glycoprotein from dry secretion of sheep is implicated as a signaling factor and is named as SPS-40. This protein is secreted only during the early phase of involution when the drastic tissue remodeling occurs in the mammary gland. SPS-40 was purified from sheep dry secretions and crystallized using hanging drop vapour diffusion method. The crystals belong to orthorhombic space group P2(1)2(1)2(1) with cell dimensions, a=62.7A, b=66.4A, c=107.5A. The protein was also cloned for the determination of its complete amino acid sequence. The three-dimensional structure of SPS-40 was determined by X-ray crystallographic method at 2.0A resolution. The structure revealed the presence of an N-linked glycan chain at Asn39. The protein adopts a conformation with a classical (beta/alpha)(8)-barrel fold of triosephosphate isomerase (TIM) (residues 1-237 and 310-360) with an insertion of a small (alpha+beta) domain (residues 240-307) similar to that observed in chitinases. However, the Leu substitution for Glu in the consensus catalytic sequence in SPS-40 causes a loss of chitinase activity. Furthermore, the sugar-binding groove in SPS-40 is distorted considerably from the standard chitin-binding site in chitinase enzymes and hence the binding of chitin-like oligosaccharides is considerably hampered. Three surface loops, His188-His197, Phe202-Arg212 and Phe244-Pro260 have exceptionally high values of B-factors (average=70.5A(2)), indicating the presence of a less defined region.
About this Structure
2DPE is a Single protein structure of sequence from Ovis aries. This structure supersedes the now removed PDB entry 1R2V. Full crystallographic information is available from OCA.
Reference
Crystal structure of a secretory signalling glycoprotein from sheep at 2.0A resolution., Srivastava DB, Ethayathulla AS, Kumar J, Singh N, Sharma S, Das U, Srinivasan A, Singh TP, J Struct Biol. 2006 Dec;156(3):505-16. Epub 2006 Jun 8. PMID:16859926
Page seeded by OCA on Thu Feb 21 17:01:10 2008
