We apologize for Proteopedia being slow to respond. For the past two years, a new implementation of Proteopedia has been being built. Soon, it will replace this 18-year old system. All existing content will be moved to the new system at a date that will be announced here.

1yf8

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1yf8.gif|left|200px]]
+
{{Seed}}
 +
[[Image:1yf8.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1yf8| PDB=1yf8 | SCENE= }}
{{STRUCTURE_1yf8| PDB=1yf8 | SCENE= }}
-
'''Crystal structure of Himalayan mistletoe RIP reveals the presence of a natural inhibitor and a new functionally active sugar-binding site'''
+
===Crystal structure of Himalayan mistletoe RIP reveals the presence of a natural inhibitor and a new functionally active sugar-binding site===
-
==Overview==
+
<!--
-
Ribosome-inactivating proteins (RIPs) are toxins involved in plant defense. How the plant prevents autotoxicity is not yet fully understood. The present study is the first structural evidence of a naturally inhibited form of RIP from a plant. Himalayan mistletoe RIP (HmRIP) was purified from Viscum album leaves and crystallized with lactose. The structure was determined by the molecular replacement method and refined at 2.8-A resolution. The crystal structure revealed the presence of high quality non-protein electron density at the active site, into which a pteridine derivative (2-amino 4-isopropyl 6-carboxyl pteridine) was modeled. The carboxyl group of the ligand binds strongly with the key active site residue Arg(162), nullifies the positive charge required for catalysis, and thereby acts as a natural inhibitor. Lectin subunits of RIPs have two active sugar-binding sites present in 1alpha- and 2gamma-subdomains. A third functionally active site has been identified in the 1beta-subdomain of HmRIP. The 1beta-site is active despite the absence of conserved polar sugar-binding residues. Loss of these residues is compensated by the following: (i) the presence of an extended site where the penultimate sugar also interacts with the protein; (ii) the interactions of galactose with the protein main chain carbonyl and amide nitrogen atoms; (iii) the presence of a well defined pocket encircled by four walls; and (iv) a favorable stacking of the galactose ring with Tyr(66) besides the conserved Phe(75). The mode of sugar binding is also distinct at the 1alpha and 2gamma sugar-binding sites.
+
The line below this paragraph, {{ABSTRACT_PUBMED_15774467}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 15774467 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_15774467}}
==About this Structure==
==About this Structure==
Line 37: Line 41:
[[Category: Sugar-binding site]]
[[Category: Sugar-binding site]]
[[Category: Viscum album]]
[[Category: Viscum album]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 16:14:51 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 14:24:27 2008''

Revision as of 11:24, 28 July 2008

Image:1yf8.png

Template:STRUCTURE 1yf8

Crystal structure of Himalayan mistletoe RIP reveals the presence of a natural inhibitor and a new functionally active sugar-binding site

Template:ABSTRACT PUBMED 15774467

About this Structure

1YF8 is a Protein complex structure of sequences from Viscum album. Full crystallographic information is available from OCA.

Reference

Crystal structure of himalayan mistletoe ribosome-inactivating protein reveals the presence of a natural inhibitor and a new functionally active sugar-binding site., Mishra V, Bilgrami S, Sharma RS, Kaur P, Yadav S, Krauspenhaar R, Betzel C, Voelter W, Babu CR, Singh TP, J Biol Chem. 2005 May 27;280(21):20712-21. Epub 2005 Mar 17. PMID:15774467

Page seeded by OCA on Mon Jul 28 14:24:27 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1yf8"
Personal tools