1pc8
From Proteopedia
(New page: 200px<br /><applet load="1pc8" size="450" color="white" frame="true" align="right" spinBox="true" caption="1pc8, resolution 3.80Å" /> '''Crystal Structure of...) |
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| - | [[Image:1pc8.gif|left|200px]]<br /><applet load="1pc8" size=" | + | [[Image:1pc8.gif|left|200px]]<br /><applet load="1pc8" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1pc8, resolution 3.80Å" /> | caption="1pc8, resolution 3.80Å" /> | ||
'''Crystal Structure of a novel form of mistletoe lectin from Himalayan Viscum album L. at 3.8A resolution'''<br /> | '''Crystal Structure of a novel form of mistletoe lectin from Himalayan Viscum album L. at 3.8A resolution'''<br /> | ||
==Overview== | ==Overview== | ||
| - | This is the first report of the structural studies of a novel | + | This is the first report of the structural studies of a novel ribosome-inactivating protein (RIP) obtained from the Himalayan mistletoe (Viscum album) (HmRip). HmRip is a type II heterodimeric protein consisting of a toxic enzyme (A-chain) with an active site for ribosome inactivation and a lectin subunit (B-chain) with well defined sugar-binding sites. The crystal structure of HmRip has been determined at 3.8 A resolution and refined to a crystallographic R factor of 0.228 (R(free) = 0.271). A comparison of this structure with other type II RIPs reveals the presence of distinct structural features in the active site of the A-chain and in the 2gamma sugar-binding site of the B-chain. The conformation of the side chain of Tyr110, which is a conserved active-site residue in the A subunit, is strikingly different from those observed in other mistletoe RIPs, indicating its unique substrate-binding preference. The deletion of two important residues from the kink region after Ala231 in the 2gamma subdomain of the B-chain results in a significantly different conformation of the sugar-binding pocket. A ribosome-recognition site has also been identified in HmRip. The site is a shallow cavity, with the conserved residues Arg51, Asp70, Thr72 and Asn73 involved in the binding. The conformations of the antigenic epitopes of residues 1-20, 85-103 and 206-223 differ from those observed in other type II RIPs, resulting in the distinct antigenicity and pharmacological properties of HmRip. |
==About this Structure== | ==About this Structure== | ||
| - | 1PC8 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Viscum_album Viscum album] with NAG as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/rRNA_N-glycosylase rRNA N-glycosylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.22 3.2.2.22] Full crystallographic information is available from [http:// | + | 1PC8 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Viscum_album Viscum album] with <scene name='pdbligand=NAG:'>NAG</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/rRNA_N-glycosylase rRNA N-glycosylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.22 3.2.2.22] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PC8 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Viscum album]] | [[Category: Viscum album]] | ||
[[Category: rRNA N-glycosylase]] | [[Category: rRNA N-glycosylase]] | ||
| - | [[Category: Babu, C | + | [[Category: Babu, C R.]] |
| - | [[Category: Ethayathulla, A | + | [[Category: Ethayathulla, A S.]] |
[[Category: Kaur, P.]] | [[Category: Kaur, P.]] | ||
[[Category: Mishra, V.]] | [[Category: Mishra, V.]] | ||
[[Category: Paramasivam, M.]] | [[Category: Paramasivam, M.]] | ||
| - | [[Category: Sharma, R | + | [[Category: Sharma, R S.]] |
[[Category: Singh, G.]] | [[Category: Singh, G.]] | ||
| - | [[Category: Singh, T | + | [[Category: Singh, T P.]] |
[[Category: Yadav, S.]] | [[Category: Yadav, S.]] | ||
[[Category: NAG]] | [[Category: NAG]] | ||
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[[Category: novel form]] | [[Category: novel form]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:27:19 2008'' |
Revision as of 12:27, 21 February 2008
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Crystal Structure of a novel form of mistletoe lectin from Himalayan Viscum album L. at 3.8A resolution
Overview
This is the first report of the structural studies of a novel ribosome-inactivating protein (RIP) obtained from the Himalayan mistletoe (Viscum album) (HmRip). HmRip is a type II heterodimeric protein consisting of a toxic enzyme (A-chain) with an active site for ribosome inactivation and a lectin subunit (B-chain) with well defined sugar-binding sites. The crystal structure of HmRip has been determined at 3.8 A resolution and refined to a crystallographic R factor of 0.228 (R(free) = 0.271). A comparison of this structure with other type II RIPs reveals the presence of distinct structural features in the active site of the A-chain and in the 2gamma sugar-binding site of the B-chain. The conformation of the side chain of Tyr110, which is a conserved active-site residue in the A subunit, is strikingly different from those observed in other mistletoe RIPs, indicating its unique substrate-binding preference. The deletion of two important residues from the kink region after Ala231 in the 2gamma subdomain of the B-chain results in a significantly different conformation of the sugar-binding pocket. A ribosome-recognition site has also been identified in HmRip. The site is a shallow cavity, with the conserved residues Arg51, Asp70, Thr72 and Asn73 involved in the binding. The conformations of the antigenic epitopes of residues 1-20, 85-103 and 206-223 differ from those observed in other type II RIPs, resulting in the distinct antigenicity and pharmacological properties of HmRip.
About this Structure
1PC8 is a Protein complex structure of sequences from Viscum album with as ligand. Active as rRNA N-glycosylase, with EC number 3.2.2.22 Full crystallographic information is available from OCA.
Reference
Structure of a novel ribosome-inactivating protein from a hemi-parasitic plant inhabiting the northwestern Himalayas., Mishra V, Ethayathulla AS, Sharma RS, Yadav S, Krauspenhaar R, Betzel C, Babu CR, Singh TP, Acta Crystallogr D Biol Crystallogr. 2004 Dec;60(Pt 12 Pt 2):2295-304., Epub 2004 Nov 26. PMID:15583377
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