1s3p

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1s3p.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:1s3p.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1s3p| PDB=1s3p | SCENE= }}
{{STRUCTURE_1s3p| PDB=1s3p | SCENE= }}
-
'''Crystal structure of rat alpha-parvalbumin S55D/E59D mutant'''
+
===Crystal structure of rat alpha-parvalbumin S55D/E59D mutant===
-
==Overview==
+
<!--
-
In model peptide systems, Ca2+ affinity is maximized in EF-hand motifs containing four carboxylates positioned on the +x and -x and +z and -z axes; introduction of a fifth carboxylate ligand reduces the affinity. However, in rat beta-parvalbumin, replacement of Ser-55 with aspartate heightens divalent ion affinity [Henzl, M. T., et al. (1996) Biochemistry 35, 5856-5869]. The corresponding alpha-parvalbumin variant (S55D/E59D) likewise exhibits elevated affinity [Henzl, M. T., et al. (2003) Anal. Biochem. 319, 216-233]. To determine whether these mutations produce a variation on the archetypal EF-hand coordination scheme, we have obtained high-resolution X-ray crystallographic data for alpha S55D/E59D. As anticipated, the aspartyl carboxylate replaces the serine hydroxyl at the +z coordination position. Interestingly, the Asp-59 carboxylate abandons the role it plays as an outer sphere ligand in wild-type rat beta, rotating away from the Ca2+ and, instead, forming a hydrogen bond with the amide of Glu-62. Superficially, the coordination sphere in the CD site of alpha S55D/E59D resembles that in the EF site. However, the orientation of the Asp-59 side chain is predicted to stabilize the D-helix, which may contribute to the heightened divalent ion affinity. DSC data indicate that the alpha S55D/E59D variant retains the capacity to bind 1 equiv of Na+. Consistent with this finding, when binding measurements are conducted in K(+)-containing buffer, divalent ion affinity is markedly higher. In 0.15 M KCl and 0.025 M Hepes-KOH (pH 7.4) at 5 degrees C, the macroscopic Ca2+ binding constants are 1.8 x 10(10) and 2.0 x 10(9) M(-1). The corresponding Mg2+ binding constants are 2.7 x 10(6) and 1.2 x 10(5) M(-1).
+
The line below this paragraph, {{ABSTRACT_PUBMED_15287728}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 15287728 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_15287728}}
==About this Structure==
==About this Structure==
Line 27: Line 31:
[[Category: Ef-hand]]
[[Category: Ef-hand]]
[[Category: Parvalbumin]]
[[Category: Parvalbumin]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 08:15:37 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 14:58:04 2008''

Revision as of 11:58, 28 July 2008

Template:STRUCTURE 1s3p

Crystal structure of rat alpha-parvalbumin S55D/E59D mutant

Template:ABSTRACT PUBMED 15287728

About this Structure

1S3P is a Single protein structure of sequence from Rattus norvegicus. Full crystallographic information is available from OCA.

Reference

Crystal structure of a high-affinity variant of rat alpha-parvalbumin., Lee YH, Tanner JJ, Larson JD, Henzl MT, Biochemistry. 2004 Aug 10;43(31):10008-17. PMID:15287728

Page seeded by OCA on Mon Jul 28 14:58:04 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools