1xmd
From Proteopedia
(New page: 200px<br /><applet load="1xmd" size="450" color="white" frame="true" align="right" spinBox="true" caption="1xmd, resolution 2.10Å" /> '''M335V mutant structu...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1xmd.gif|left|200px]]<br /><applet load="1xmd" size=" | + | [[Image:1xmd.gif|left|200px]]<br /><applet load="1xmd" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1xmd, resolution 2.10Å" /> | caption="1xmd, resolution 2.10Å" /> | ||
'''M335V mutant structure of mouse carnitine octanoyltransferase'''<br /> | '''M335V mutant structure of mouse carnitine octanoyltransferase'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Carnitine acyltransferases have crucial functions in fatty acid | + | Carnitine acyltransferases have crucial functions in fatty acid metabolism. Members of this enzyme family show distinctive substrate preferences for short-, medium- or long-chain fatty acids. The molecular mechanism for this substrate selectivity is not clear as so far only the structure of carnitine acetyltransferase has been determined. To further our understanding of these important enzymes, we report here the crystal structures at up to 2.0-A resolution of mouse carnitine octanoyltransferase alone and in complex with the substrate octanoylcarnitine. The structures reveal significant differences in the acyl group binding pocket between carnitine octanoyltransferase and carnitine acetyltransferase. Amino acid substitutions and structural changes produce a larger hydrophobic pocket that binds the octanoyl group in an extended conformation. Mutation of a single residue (Gly-553) in this pocket can change the substrate preference between short- and medium-chain acyl groups. The side chains of Cys-323 and Met-335 at the bottom of this pocket assume dual conformations in the substrate complex, and mutagenesis studies suggest that the Met-335 residue is important for catalysis. |
==About this Structure== | ==About this Structure== | ||
| - | 1XMD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] with EPE and MPD as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Carnitine_O-octanoyltransferase Carnitine O-octanoyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.1.137 2.3.1.137] Full crystallographic information is available from [http:// | + | 1XMD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] with <scene name='pdbligand=EPE:'>EPE</scene> and <scene name='pdbligand=MPD:'>MPD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Carnitine_O-octanoyltransferase Carnitine O-octanoyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.1.137 2.3.1.137] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XMD OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: Mus musculus]] | [[Category: Mus musculus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Hsiao, Y | + | [[Category: Hsiao, Y S.]] |
[[Category: Jogl, G.]] | [[Category: Jogl, G.]] | ||
[[Category: Tong, L.]] | [[Category: Tong, L.]] | ||
| Line 25: | Line 25: | ||
[[Category: octanoyltransferase]] | [[Category: octanoyltransferase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:56:21 2008'' |
Revision as of 13:56, 21 February 2008
|
M335V mutant structure of mouse carnitine octanoyltransferase
Overview
Carnitine acyltransferases have crucial functions in fatty acid metabolism. Members of this enzyme family show distinctive substrate preferences for short-, medium- or long-chain fatty acids. The molecular mechanism for this substrate selectivity is not clear as so far only the structure of carnitine acetyltransferase has been determined. To further our understanding of these important enzymes, we report here the crystal structures at up to 2.0-A resolution of mouse carnitine octanoyltransferase alone and in complex with the substrate octanoylcarnitine. The structures reveal significant differences in the acyl group binding pocket between carnitine octanoyltransferase and carnitine acetyltransferase. Amino acid substitutions and structural changes produce a larger hydrophobic pocket that binds the octanoyl group in an extended conformation. Mutation of a single residue (Gly-553) in this pocket can change the substrate preference between short- and medium-chain acyl groups. The side chains of Cys-323 and Met-335 at the bottom of this pocket assume dual conformations in the substrate complex, and mutagenesis studies suggest that the Met-335 residue is important for catalysis.
About this Structure
1XMD is a Single protein structure of sequence from Mus musculus with and as ligands. Active as Carnitine O-octanoyltransferase, with EC number 2.3.1.137 Full crystallographic information is available from OCA.
Reference
Crystal structure of mouse carnitine octanoyltransferase and molecular determinants of substrate selectivity., Jogl G, Hsiao YS, Tong L, J Biol Chem. 2005 Jan 7;280(1):738-44. Epub 2004 Oct 17. PMID:15492013
Page seeded by OCA on Thu Feb 21 15:56:21 2008
Categories: Carnitine O-octanoyltransferase | Mus musculus | Single protein | Hsiao, Y S. | Jogl, G. | Tong, L. | EPE | MPD | Carnitine | Hepes | Mpd | Mutant | Octanoyltransferase
