1sjw
From Proteopedia
(New page: 200px<br /><applet load="1sjw" size="450" color="white" frame="true" align="right" spinBox="true" caption="1sjw, resolution 1.35Å" /> '''Structure of polyket...) |
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| - | [[Image:1sjw.gif|left|200px]]<br /><applet load="1sjw" size=" | + | [[Image:1sjw.gif|left|200px]]<br /><applet load="1sjw" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1sjw, resolution 1.35Å" /> | caption="1sjw, resolution 1.35Å" /> | ||
'''Structure of polyketide cyclase SnoaL'''<br /> | '''Structure of polyketide cyclase SnoaL'''<br /> | ||
==Overview== | ==Overview== | ||
| - | SnoaL belongs to a family of small polyketide cyclases, which catalyse | + | SnoaL belongs to a family of small polyketide cyclases, which catalyse ring closure steps in the biosynthesis of polyketide antibiotics produced in Streptomyces. Several of these antibiotics are among the most used anti-cancer drugs currently in use. The crystal structure of SnoaL, involved in nogalamycin biosynthesis, with a bound product, has been determined to 1.35 A resolution. The fold of the subunit can be described as a distorted alpha+beta barrel, and the ligand is bound in the hydrophobic interior of the barrel. The 3D structure and site-directed mutagenesis experiments reveal that the mechanism of the intramolecular aldol condensation catalysed by SnoaL is different from that of the classical aldolases, which employ covalent Schiff base formation or a metal ion cofactor. The invariant residue Asp121 acts as an acid/base catalyst during the reaction. Stabilisation of the enol(ate) intermediate is mainly achieved by the delocalisation of the electron pair over the extended pi system of the substrate. These polyketide cyclases thus form of family of enzymes with a unique catalytic strategy for aldol condensation. |
==About this Structure== | ==About this Structure== | ||
| - | 1SJW is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_nogalater Streptomyces nogalater] with NGV as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1SJW is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_nogalater Streptomyces nogalater] with <scene name='pdbligand=NGV:'>NGV</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SJW OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Mantsala, P.]] | [[Category: Mantsala, P.]] | ||
[[Category: Neimi, J.]] | [[Category: Neimi, J.]] | ||
| - | [[Category: SPINE, Structural | + | [[Category: SPINE, Structural Proteomics in Europe.]] |
[[Category: Schneider, G.]] | [[Category: Schneider, G.]] | ||
[[Category: Sultana, A.]] | [[Category: Sultana, A.]] | ||
| - | [[Category: Wang, J | + | [[Category: Wang, J S.]] |
[[Category: NGV]] | [[Category: NGV]] | ||
[[Category: aldol condensation]] | [[Category: aldol condensation]] | ||
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[[Category: structural proteomics in europe]] | [[Category: structural proteomics in europe]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:02:13 2008'' |
Revision as of 13:02, 21 February 2008
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Structure of polyketide cyclase SnoaL
Overview
SnoaL belongs to a family of small polyketide cyclases, which catalyse ring closure steps in the biosynthesis of polyketide antibiotics produced in Streptomyces. Several of these antibiotics are among the most used anti-cancer drugs currently in use. The crystal structure of SnoaL, involved in nogalamycin biosynthesis, with a bound product, has been determined to 1.35 A resolution. The fold of the subunit can be described as a distorted alpha+beta barrel, and the ligand is bound in the hydrophobic interior of the barrel. The 3D structure and site-directed mutagenesis experiments reveal that the mechanism of the intramolecular aldol condensation catalysed by SnoaL is different from that of the classical aldolases, which employ covalent Schiff base formation or a metal ion cofactor. The invariant residue Asp121 acts as an acid/base catalyst during the reaction. Stabilisation of the enol(ate) intermediate is mainly achieved by the delocalisation of the electron pair over the extended pi system of the substrate. These polyketide cyclases thus form of family of enzymes with a unique catalytic strategy for aldol condensation.
About this Structure
1SJW is a Single protein structure of sequence from Streptomyces nogalater with as ligand. Full crystallographic information is available from OCA.
Reference
Structure of the polyketide cyclase SnoaL reveals a novel mechanism for enzymatic aldol condensation., Sultana A, Kallio P, Jansson A, Wang JS, Niemi J, Mantsala P, Schneider G, EMBO J. 2004 May 5;23(9):1911-21. Epub 2004 Apr 8. PMID:15071504
Page seeded by OCA on Thu Feb 21 15:02:13 2008
Categories: Single protein | Streptomyces nogalater | Jansson, A. | Kallio, P. | Mantsala, P. | Neimi, J. | SPINE, Structural Proteomics in Europe. | Schneider, G. | Sultana, A. | Wang, J S. | NGV | Aldol condensation | Anthracyclines | Crystal structure | Nogalamycin | Snoal | Spine | Structural genomics | Structural proteomics in europe
