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.


1os1

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1os1.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:1os1.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1os1| PDB=1os1 | SCENE= }}
{{STRUCTURE_1os1| PDB=1os1 | SCENE= }}
-
'''Structure of Phosphoenolpyruvate Carboxykinase complexed with ATP,Mg, Ca and pyruvate.'''
+
===Structure of Phosphoenolpyruvate Carboxykinase complexed with ATP,Mg, Ca and pyruvate.===
-
==Overview==
+
<!--
-
The 1.8-A resolution structure of the ATP-Mg(2+)-Ca(2+)-pyruvate quinary complex of Escherichia coli phosphoenolpyruvate carboxykinase (PCK) is isomorphous to the published complex ATP-Mg(2+)-Mn(2+)-pyruvate-PCK, except for the Ca(2+) and Mn(2+) binding sites. Ca(2+) was formerly implicated as a possible allosteric regulator of PCK, binding at the active site and at a surface activating site (Glu508 and Glu511). This report found that Ca(2+) bound only at the active site, indicating that there is likely no surface allosteric site. (45)Ca(2+) bound to PCK with a K(d) of 85 micro M and n of 0.92. Glu508Gln Glu511Gln mutant PCK had normal activation by Ca(2+). Separate roles of Mg(2+), which binds the nucleotide, and Ca(2+), which bridges the nucleotide and the anionic substrate, are implied, and the catalytic mechanism of PCK is better explained by studies of the Ca(2+)-bound structure. Partial trypsin digestion abolishes Ca(2+) activation (desensitizes PCK). N-terminal sequencing identified sensitive sites, i.e., Arg2 and Arg396. Arg2Ser, Arg396Ser, and Arg2Ser Arg396Ser (double mutant) PCKs altered the kinetics of desensitization. C-terminal residues 397 to 540 were removed by trypsin when wild-type PCK was completely desensitized. Phe409 and Phe413 interact with residues in the Ca(2+) binding site, probably stabilizing the C terminus. Phe409Ala, DeltaPhe409, Phe413Ala, Delta397-521 (deletion of residues 397 to 521), Arg396(TAA) (stop codon), and Asp269Glu (Ca(2+) site) mutations failed to desensitize PCK and, with the exception of Phe409Ala, appeared to have defects in the synthesis or assembly of PCK, suggesting that the structure of the C-terminal domain is important in these processes.
+
The line below this paragraph, {{ABSTRACT_PUBMED_12837799}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 12837799 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_12837799}}
==About this Structure==
==About this Structure==
Line 31: Line 35:
[[Category: Enzyme mechanism]]
[[Category: Enzyme mechanism]]
[[Category: Phosphotransfer,calcium,activation]]
[[Category: Phosphotransfer,calcium,activation]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 04:12:52 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Jul 27 22:21:51 2008''

Revision as of 19:21, 27 July 2008

Image:1os1.png

Template:STRUCTURE 1os1

Structure of Phosphoenolpyruvate Carboxykinase complexed with ATP,Mg, Ca and pyruvate.

Template:ABSTRACT PUBMED 12837799

About this Structure

1OS1 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.

Reference

Mechanisms of activation of phosphoenolpyruvate carboxykinase from Escherichia coli by Ca2+ and of desensitization by trypsin., Sudom A, Walters R, Pastushok L, Goldie D, Prasad L, Delbaere LT, Goldie H, J Bacteriol. 2003 Jul;185(14):4233-42. PMID:12837799

Page seeded by OCA on Sun Jul 27 22:21:51 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1os1"
Personal tools