1qjf
From Proteopedia
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| - | [[Image:1qjf.jpg|left|200px]]<br /><applet load="1qjf" size=" | + | [[Image:1qjf.jpg|left|200px]]<br /><applet load="1qjf" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1qjf, resolution 1.40Å" /> | caption="1qjf, resolution 1.40Å" /> | ||
'''ISOPENICILLIN N SYNTHASE FROM ASPERGILLUS NIDULANS (MONOCYCLIC SULFOXIDE-FE COMPLEX)'''<br /> | '''ISOPENICILLIN N SYNTHASE FROM ASPERGILLUS NIDULANS (MONOCYCLIC SULFOXIDE-FE COMPLEX)'''<br /> | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1QJF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Emericella_nidulans Emericella nidulans] with SO4, FE2 and ACS as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Site: <scene name='pdbsite=SA:Active Site (Fe Binding)'>SA</scene>. Full crystallographic information is available from [http:// | + | 1QJF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Emericella_nidulans Emericella nidulans] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=FE2:'>FE2</scene> and <scene name='pdbligand=ACS:'>ACS</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Site: <scene name='pdbsite=SA:Active+Site+(Fe+Binding)'>SA</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QJF OCA]. |
==Reference== | ==Reference== | ||
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[[Category: sulfoxide]] | [[Category: sulfoxide]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Feb 3 10:00:30 2008'' |
Revision as of 08:00, 3 February 2008
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ISOPENICILLIN N SYNTHASE FROM ASPERGILLUS NIDULANS (MONOCYCLIC SULFOXIDE-FE COMPLEX)
Overview
Isopenicillin N synthase (IPNS), a non-haem iron-dependent oxidase, catalyses the biosynthesis of isopenicillin N (IPN), the precursor of all, penicillins and cephalosporins. The key steps in this reaction are the two, iron-dioxygen-mediated ring closures of the tripeptide, delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-valine (ACV). It has been, proposed that the four-membered beta-lactam ring forms initially, associated with a highly oxidized iron(iv)-oxo (ferryl) moiety, which, subsequently mediates closure of the five-membered thiazolidine ring. Here, we describe observation of the IPNS reaction in crystals by X-ray, crystallography. IPNS Fe2+ substrate crystals were grown anaerobically, exposed to high pressures of oxygen to promote reaction and frozen, and, their structures were elucidated by X-ray diffraction. Using the natural, substrate ACV, this resulted in the IPNS x Fe2+ x IPN product complex., With the substrate analogue, delta-(L-alpha-aminoadipoyl)-L-cysteinyl-L-S-methylcysteine (ACmC) in the, crystal, the reaction cycle was interrupted at the monocyclic stage. These, mono- and bicyclic structures support our hypothesis of a two-stage, reaction sequence leading to penicillin. Furthermore, the formation of a, monocyclic sulphoxide product from ACmC is most simply explained by the, interception of a high-valency iron-oxo species.
About this Structure
1QJF is a Single protein structure of sequence from Emericella nidulans with , and as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
The reaction cycle of isopenicillin N synthase observed by X-ray diffraction., Burzlaff NI, Rutledge PJ, Clifton IJ, Hensgens CM, Pickford M, Adlington RM, Roach PL, Baldwin JE, Nature. 1999 Oct 14;401(6754):721-4. PMID:10537113
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