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1hjg
From Proteopedia
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| - | [[Image:1hjg.gif|left|200px]]<br /> | + | [[Image:1hjg.gif|left|200px]]<br /><applet load="1hjg" size="450" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1hjg" size="450" color="white" frame="true" align="right" spinBox="true" | + | |
caption="1hjg, resolution 1.5Å" /> | caption="1hjg, resolution 1.5Å" /> | ||
'''ALTERATION OF THE CO-SUBSTRATE SELECTIVITY OF DEACETOXYCEPHALOSPORIN C SYNTHASE: THE ROLE OF ARGININE-258'''<br /> | '''ALTERATION OF THE CO-SUBSTRATE SELECTIVITY OF DEACETOXYCEPHALOSPORIN C SYNTHASE: THE ROLE OF ARGININE-258'''<br /> | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1HJG is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_clavuligerus Streptomyces clavuligerus] with FE2 and KIV as [http://en.wikipedia.org/wiki/ligands ligands]. | + | 1HJG is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_clavuligerus Streptomyces clavuligerus] with FE2 and KIV as [http://en.wikipedia.org/wiki/ligands ligands]. Known structural/functional Sites: <scene name='pdbsite=FE:Protein Fe-Binding Ligands. 2-Oxo-3-Methylbutanoate Cosu ...'>FE</scene> and <scene name='pdbsite=KIV:Kiv Binding Site For Chain A'>KIV</scene>. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1HJG OCA]. |
==Reference== | ==Reference== | ||
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[[Category: co-substrate selectivity]] | [[Category: co-substrate selectivity]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Dec 18 16:26:14 2007'' |
Revision as of 14:16, 18 December 2007
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ALTERATION OF THE CO-SUBSTRATE SELECTIVITY OF DEACETOXYCEPHALOSPORIN C SYNTHASE: THE ROLE OF ARGININE-258
Overview
Deacetoxycephalosporin C synthase is an iron(II) 2-oxoglutaratedependent, oxygenase that catalyzes the oxidative ring-expansion of penicillin N to, deacetoxycephalosporin C. The wild-type enzyme is only able to efficiently, utilize 2-oxoglutarate and 2-oxoadipate as a 2-oxoacid co-substrate., Mutation of arginine 258, the side chain of which forms an electrostatic, interaction with the 5-carboxylate of the 2-oxoglutarate co-substrate, to, a glutamine residue reduced activity to about 5% of the wild-type enzyme, with 2-oxoglutarate. However, other aliphatic 2-oxoacids, which were not, co-substrates for the wild-type enzyme, were utilized by the R258Q mutant., These 2-oxoacids "rescued" catalytic activity to the level observed for, the wild-type enzyme as judged by penicillin N and G conversion. These, co-substrates underwent oxidative decarboxylation as observed for, 2-oxoglutarate in the normal reaction with the wild-type enzyme. Crystal, structures of the iron(II)- 2-oxo-3-methylbutanoate (1.5 A), and, iron(II)-2-oxo-4-methylpentanoate (1.6 A) enzyme complexes were obtained, which reveal the molecular basis for this "chemical co-substrate rescue", and help to rationalize the co-substrate selectivity of, 2-oxoglutaratedependent oxygenases.
About this Structure
1HJG is a Single protein structure of sequence from Streptomyces clavuligerus with FE2 and KIV as ligands. Known structural/functional Sites: and . Full crystallographic information is available from OCA.
Reference
Alteration of the co-substrate selectivity of deacetoxycephalosporin C synthase. The role of arginine 258., Lee HJ, Lloyd MD, Clifton IJ, Harlos K, Dubus A, Baldwin JE, Frere JM, Schofield CJ, J Biol Chem. 2001 May 25;276(21):18290-5. Epub 2001 Feb 21. PMID:11279000
Page seeded by OCA on Tue Dec 18 16:26:14 2007
Categories: Single protein | Streptomyces clavuligerus | Baldwin, J.E. | Clifton, I.J. | Dubus, A. | Frere, J.M. | Harlos, K. | Lee, H.J. | Lloyd, M.D. | Schofield, C.J. | FE2 | KIV | 2-oxoglutarate-dependent oxygenase | Alternative 2-oxoacids | Cephem antibiotic biosynthesis | Chemical cosubstrate rescue | Co-substrate selectivity
