2a89
From Proteopedia
(New page: 200px<br /><applet load="2a89" size="450" color="white" frame="true" align="right" spinBox="true" caption="2a89, resolution 1.85Å" /> '''Monomeric Sarcosine ...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:2a89.gif|left|200px]]<br /><applet load="2a89" size=" | + | [[Image:2a89.gif|left|200px]]<br /><applet load="2a89" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2a89, resolution 1.85Å" /> | caption="2a89, resolution 1.85Å" /> | ||
'''Monomeric Sarcosine Oxidase: Structure of a covalently flavinylated amine oxidizing enzyme'''<br /> | '''Monomeric Sarcosine Oxidase: Structure of a covalently flavinylated amine oxidizing enzyme'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Monomeric sarcosine oxidase (MSOX) is a flavoprotein that contains | + | Monomeric sarcosine oxidase (MSOX) is a flavoprotein that contains covalently bound FAD [8a-(S-cysteinyl)FAD] and catalyzes the oxidation of sarcosine (N-methylglycine) and other secondary amino acids, such as l-proline. Our previous studies showed that N-(cyclopropyl)glycine (CPG) acts as a mechanism-based inactivator of MSOX [Zhao, G., et al. (2000) Biochemistry 39, 14341-14347]. The reaction results in the formation of a modified reduced flavin that can be further reduced and stabilized by treatment with sodium borohydride. The borohydride-reduced CPG-modified enzyme exhibits a mass increase of 63 +/- 2 Da as compared with native MSOX. The crystal structure of the modified enzyme, solved at 1.85 A resolution, shows that FAD is the only site of modification. The modified FAD contains a fused five-membered ring, linking the C(4a) and N(5) atoms of the flavin ring, with an additional oxygen atom bound to the carbon atom attached to N(5) and a tetrahedral carbon atom at flavin C(4) with a hydroxyl group attached to C(4). On the basis of the crystal structure of the borohydride-stabilized adduct, we conclude that the labile CPG-modified flavin is a 4a,5-dihydroflavin derivative with a substituent derived from the cleavage of the cyclopropyl ring in CPG. The results are consistent with CPG-mediated inactivation in a reaction initiated by single electron transfer from the amine function in CPG to FAD in MSOX, followed by collapse of the radical pair to yield a covalently modified 4a,5-dihydroflavin. |
==About this Structure== | ==About this Structure== | ||
| - | 2A89 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_sp. Bacillus sp.] with PO4, CL and FCG as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Sarcosine_oxidase Sarcosine oxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.5.3.1 1.5.3.1] Full crystallographic information is available from [http:// | + | 2A89 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_sp. Bacillus sp.] with <scene name='pdbligand=PO4:'>PO4</scene>, <scene name='pdbligand=CL:'>CL</scene> and <scene name='pdbligand=FCG:'>FCG</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Sarcosine_oxidase Sarcosine oxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.5.3.1 1.5.3.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2A89 OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: Sarcosine oxidase]] | [[Category: Sarcosine oxidase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Chen, Z | + | [[Category: Chen, Z W.]] |
| - | [[Category: Jorns, M | + | [[Category: Jorns, M S.]] |
[[Category: Martinovic, S.]] | [[Category: Martinovic, S.]] | ||
| - | [[Category: Mathews, F | + | [[Category: Mathews, F S.]] |
[[Category: Zhao, G.]] | [[Category: Zhao, G.]] | ||
[[Category: CL]] | [[Category: CL]] | ||
| Line 25: | Line 25: | ||
[[Category: oxidase]] | [[Category: oxidase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:24:34 2008'' |
Revision as of 14:24, 21 February 2008
|
Monomeric Sarcosine Oxidase: Structure of a covalently flavinylated amine oxidizing enzyme
Overview
Monomeric sarcosine oxidase (MSOX) is a flavoprotein that contains covalently bound FAD [8a-(S-cysteinyl)FAD] and catalyzes the oxidation of sarcosine (N-methylglycine) and other secondary amino acids, such as l-proline. Our previous studies showed that N-(cyclopropyl)glycine (CPG) acts as a mechanism-based inactivator of MSOX [Zhao, G., et al. (2000) Biochemistry 39, 14341-14347]. The reaction results in the formation of a modified reduced flavin that can be further reduced and stabilized by treatment with sodium borohydride. The borohydride-reduced CPG-modified enzyme exhibits a mass increase of 63 +/- 2 Da as compared with native MSOX. The crystal structure of the modified enzyme, solved at 1.85 A resolution, shows that FAD is the only site of modification. The modified FAD contains a fused five-membered ring, linking the C(4a) and N(5) atoms of the flavin ring, with an additional oxygen atom bound to the carbon atom attached to N(5) and a tetrahedral carbon atom at flavin C(4) with a hydroxyl group attached to C(4). On the basis of the crystal structure of the borohydride-stabilized adduct, we conclude that the labile CPG-modified flavin is a 4a,5-dihydroflavin derivative with a substituent derived from the cleavage of the cyclopropyl ring in CPG. The results are consistent with CPG-mediated inactivation in a reaction initiated by single electron transfer from the amine function in CPG to FAD in MSOX, followed by collapse of the radical pair to yield a covalently modified 4a,5-dihydroflavin.
About this Structure
2A89 is a Single protein structure of sequence from Bacillus sp. with , and as ligands. Active as Sarcosine oxidase, with EC number 1.5.3.1 Full crystallographic information is available from OCA.
Reference
Structure of the sodium borohydride-reduced N-(cyclopropyl)glycine adduct of the flavoenzyme monomeric sarcosine oxidase., Chen ZW, Zhao G, Martinovic S, Jorns MS, Mathews FS, Biochemistry. 2005 Nov 29;44(47):15444-50. PMID:16300392
Page seeded by OCA on Thu Feb 21 16:24:34 2008
Categories: Bacillus sp. | Sarcosine oxidase | Single protein | Chen, Z W. | Jorns, M S. | Martinovic, S. | Mathews, F S. | Zhao, G. | CL | FCG | PO4 | Flavoprotein | Oxidase
