1rtc

From Proteopedia

(Difference between revisions)

Revision as of 07:06, 8 March 2018

THE STRUCTURE OF RECOMBINANT RICIN A CHAIN AT 2.3 ANGSTROMS

Structural highlights

1rtc is a 1 chain structure with sequence from Castor bean. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Activity:	rRNA N-glycosylase, with EC number 3.2.2.22
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[RICI_RICCO] Ricin is highly toxic to animal cells and to a lesser extent to plant cells. The A chain acts as a glycosidase that removes a specific adenine residue from an exposed loop of the 28S rRNA (A4324 in mammals), leading to rRNA breakage. As this loop is involved in elongation factor binding, modified ribosomes are catalytically inactive and unable to support protein synthesis. The A chain can inactivate a few thousand ribosomes per minute, faster than the cell can make new ones. Therefore a single A chain molecule can kill an animal cell. The B chain binds to beta-D-galactopyranoside moieties on cell surface glycoproteins and glycolipids and facilitates the entry into the cell of the A chain; B chains are also responsible for cell agglutination (Lectin activity).

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The plant cytotoxin ricin is a heterodimer with a cell surface binding (B) chain and an enzymatically active A chain (RTA) known to act as a specific N-glycosidase. RTA must be separated from B chain to attack rRNA. The X-ray structure of ricin has been solved recently; here we report the structure of the isolated A chain expressed from a clone in Escherichia coli. This structure of wild-type rRTA has and will continue to serve as the parent compound for difference Fouriers used to assess the structure of site-directed mutants designed to analyze the mechanism of this medically and commercially important toxin. The structure of the recombinant protein, rRTA, is virtually identical to that seen previously for A chain in the heterodimeric toxin. Some minor conformational changes due to interactions with B chain and to crystal packing differences are described. Perhaps the most significant difference is the presence in rRTA of an additional active site water. This molecule is positioned to act as the ultimate nucleophile in the depurination reaction mechanism proposed by Monzingo and Robertus (1992, J. Mol. Biol. 227, 1136-1145).

Structure of recombinant ricin A chain at 2.3 A.,Mlsna D, Monzingo AF, Katzin BJ, Ernst S, Robertus JD Protein Sci. 1993 Mar;2(3):429-35. PMID:8453380^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Mlsna D, Monzingo AF, Katzin BJ, Ernst S, Robertus JD. Structure of recombinant ricin A chain at 2.3 A. Protein Sci. 1993 Mar;2(3):429-35. PMID:8453380

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1rtc"

@@ Line 1: / Line 1: @@
 ==THE STRUCTURE OF RECOMBINANT RICIN A CHAIN AT 2.3 ANGSTROMS==
 <StructureSection load='1rtc' size='340' side='right' caption='[[1rtc]], [[Resolution|resolution]] 2.30&Aring;' scene=''>
@@ Line 4: / Line 5: @@
 <table><tr><td colspan='2'>[[1rtc]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Castor_bean Castor bean]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1RTC OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1RTC FirstGlance]. <br>
 </td></tr><tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[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] </span></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1rtc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1rtc OCA], [http://pdbe.org/1rtc PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1rtc RCSB], [http://www.ebi.ac.uk/pdbsum/1rtc PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1rtc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1rtc OCA], [http://pdbe.org/1rtc PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1rtc RCSB], [http://www.ebi.ac.uk/pdbsum/1rtc PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1rtc ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 12: / Line 13: @@
 Check<jmol>
   <jmolCheckbox>
-    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/rt/1rtc_consurf.spt"</scriptWhenChecked>
+    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/rt/1rtc_consurf.spt"</scriptWhenChecked>
     <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
     <text>to colour the structure by Evolutionary Conservation</text>

1rtc

From Proteopedia

Revision as of 07:06, 8 March 2018

THE STRUCTURE OF RECOMBINANT RICIN A CHAIN AT 2.3 ANGSTROMS

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox