2axe: Difference between revisions
From Proteopedia
Jump to navigationJump to search
New page: left|200px<br /><applet load="2axe" size="450" color="white" frame="true" align="right" spinBox="true" caption="2axe, resolution 1.80Å" /> '''IODINATED COMPLEX OF... |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:2axe.gif|left|200px]]<br /><applet load="2axe" size=" | [[Image:2axe.gif|left|200px]]<br /><applet load="2axe" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="2axe, resolution 1.80Å" /> | caption="2axe, resolution 1.80Å" /> | ||
'''IODINATED COMPLEX OF ACETYL XYLAN ESTERASE AT 1.80 ANGSTROMS'''<br /> | '''IODINATED COMPLEX OF ACETYL XYLAN ESTERASE AT 1.80 ANGSTROMS'''<br /> | ||
==Overview== | ==Overview== | ||
Enzymatic and non-enzymatic iodination of the amino acid tyrosine is a | Enzymatic and non-enzymatic iodination of the amino acid tyrosine is a well known phenomenon. The iodination technique has been widely used for labeling proteins. Using high-resolution X-ray crystallographic techniques, the chemical and three-dimensional structures of iodotyrosines formed by non-enzymatic incorporation of I atoms into tyrosine residues of a crystalline protein are described. Acetylxylan esterase (AXE II; 207 amino-acid residues) from Penicillium purpurogenum has substrate specificities towards acetate esters of D-xylopyranose residues in xylan and belongs to a new class of alpha/beta hydrolases. The crystals of the enzyme are highly ordered, tightly packed and diffract to better than sub-angstrom resolution at 85 K. The iodination technique has been utilized to prepare an isomorphous derivative of the AXE II crystal. The structure of the enzyme determined at 1.10 A resolution exclusively by normal and anomalous scattering from I atoms, along with the structure of the iodinated complex at 1.80 A resolution, demonstrate the formation of covalent bonds between I atoms and C atoms at ortho positions to the hydroxyl groups of two tyrosyl moieties, yielding iodotyrosines. | ||
==About this Structure== | ==About this Structure== | ||
2AXE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Penicillium_purpurogenum Penicillium purpurogenum] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Acetylesterase Acetylesterase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.6 3.1.1.6] Full crystallographic information is available from [http:// | 2AXE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Penicillium_purpurogenum Penicillium purpurogenum] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Acetylesterase Acetylesterase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.6 3.1.1.6] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AXE OCA]. | ||
==Reference== | ==Reference== | ||
| Line 21: | Line 21: | ||
[[Category: Li, N.]] | [[Category: Li, N.]] | ||
[[Category: Pangborn, W.]] | [[Category: Pangborn, W.]] | ||
[[Category: Sawicki, M | [[Category: Sawicki, M W.]] | ||
[[Category: Thiel, D | [[Category: Thiel, D J.]] | ||
[[Category: Weeks, D | [[Category: Weeks, D R.]] | ||
[[Category: SO4]] | [[Category: SO4]] | ||
[[Category: esterase]] | [[Category: esterase]] | ||
| Line 29: | Line 29: | ||
[[Category: iodotyrosines]] | [[Category: iodotyrosines]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:32:01 2008'' | ||
