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.


1yma

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1yma.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:1yma.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1yma| PDB=1yma | SCENE= }}
{{STRUCTURE_1yma| PDB=1yma | SCENE= }}
-
'''STRUCTURAL CHARACTERIZATION OF HEME LIGATION IN THE HIS64-->TYR VARIANT OF MYOGLOBIN'''
+
===STRUCTURAL CHARACTERIZATION OF HEME LIGATION IN THE HIS64-->TYR VARIANT OF MYOGLOBIN===
-
==Overview==
+
<!--
-
A site-specific mutant of horse heart myoglobin has been prepared in which the distal heme pocket residue, His64, is replaced by tyrosine. The structure of this myoglobin variant has been determined to 2.0-A resolution using x-ray diffraction techniques and refined to a final crystallographic R-factor of 16.9%. The polypeptide backbone conformation of the His64--&gt;Tyr variant of myoglobin is very similar to that of the wild-type protein. However, in the variant the water normally found coordinated to the heme iron atom and hydrogen-bonded to His64 has been displaced by the hydroxyl oxygen of the Tyr64 side chain. The tyrosine oxygen atom is directly coordinated to the heme iron atom with a bond length of 2.18 A. Distortion of heme planarity and changes in the packing of the Leu29 and Leu104 side chains are related to this mutation. The ligand environment of the ferric iron has been studied by electron paramagnetic resonance (EPR) spectroscopy using crystalline material and protein in solution. The protein in solution exhibits a rhombically split ferric high spin EPR spectrum with g values of 6.64, 5.34, and 1.98. The EPR spectrum of the crystalline sample consists of two different ferric high spin signals. The main signal is similar to the signal observed in solution and is assigned to His93-Fe(III)-Tyr64 coordination. The relatively high rhombicity of this signal can be explained as arising from distortions of the heme plane seen in the crystal structure. The second, more axial high spin signal found in the crystalline state can be tentatively assigned to another form of iron ligation with a different iron-tyrosine bond length and a less distorted heme plane.
+
The line below this paragraph, {{ABSTRACT_PUBMED_8175669}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 8175669 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_8175669}}
==About this Structure==
==About this Structure==
Line 25: Line 29:
[[Category: Maurus, R.]]
[[Category: Maurus, R.]]
[[Category: Oxygen transport]]
[[Category: Oxygen transport]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 16:30:17 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Jul 27 15:04:29 2008''

Revision as of 12:04, 27 July 2008

Image:1yma.png

Template:STRUCTURE 1yma

STRUCTURAL CHARACTERIZATION OF HEME LIGATION IN THE HIS64-->TYR VARIANT OF MYOGLOBIN

Template:ABSTRACT PUBMED 8175669

About this Structure

1YMA is a Single protein structure of sequence from Equus caballus. Full crystallographic information is available from OCA.

Reference

Structural characterization of heme ligation in the His64-->Tyr variant of myoglobin., Maurus R, Bogumil R, Luo Y, Tang HL, Smith M, Mauk AG, Brayer GD, J Biol Chem. 1994 Apr 29;269(17):12606-10. PMID:8175669

Page seeded by OCA on Sun Jul 27 15:04:29 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

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