This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


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