1mb9
From Proteopedia
(New page: 200px<br /><applet load="1mb9" size="450" color="white" frame="true" align="right" spinBox="true" caption="1mb9, resolution 2.11Å" /> '''BETA-LACTAM SYNTHETA...) |
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| - | [[Image:1mb9.gif|left|200px]]<br /><applet load="1mb9" size=" | + | [[Image:1mb9.gif|left|200px]]<br /><applet load="1mb9" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1mb9, resolution 2.11Å" /> | caption="1mb9, resolution 2.11Å" /> | ||
'''BETA-LACTAM SYNTHETASE COMPLEXED WITH ATP'''<br /> | '''BETA-LACTAM SYNTHETASE COMPLEXED WITH ATP'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The catalytic cycle of the ATP/Mg(2+)-dependent enzyme beta-lactam | + | The catalytic cycle of the ATP/Mg(2+)-dependent enzyme beta-lactam synthetase (beta-LS) from Streptomyces clavuligerus has been observed through a series of x-ray crystallographic snapshots. Chemistry is initiated by the ordered binding of ATP/Mg(2+) and N(2)-(carboxyethyl)-l-arginine (CEA) to the apoenzyme. The apo and ATP/Mg(2+) structures described here, along with the previously described CEA.alpha,beta-methyleneadenosine 5'-triphosphate (CEA.AMP-CPP)/Mg(2+) structure, illuminate changes in active site geometry that favor adenylation. In addition, an acyladenylate intermediate has been trapped. The substrate analog N(2)-(carboxymethyl)-l-arginine (CMA) was adenylated by ATP in the crystal and represents a close structural analog of the previously proposed CEA-adenylate intermediate. Finally, the structure of the ternary product complex deoxyguanidinoproclavaminic acid (DGPC).AMP/PP(i)/Mg(2+) has been determined. The CMA-AMP/PP(i)/Mg(2+) and DGPC.AMP/PP(i)/Mg(2+) structures reveal interactions in the active site that facilitate beta-lactam formation. All of the ATP-bound structures differ from the previously described CEA.AMP-CPP/Mg(2+) structure in that two Mg(2+) ions are found in the active sites. These Mg(2+) ions play critical roles in both the adenylation and beta-lactamization reactions. |
==About this Structure== | ==About this Structure== | ||
| - | 1MB9 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 MG, ATP, POP and AMP as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1MB9 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 <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=ATP:'>ATP</scene>, <scene name='pdbligand=POP:'>POP</scene> and <scene name='pdbligand=AMP:'>AMP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MB9 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Streptomyces clavuligerus]] | [[Category: Streptomyces clavuligerus]] | ||
| - | [[Category: Bachmann, B | + | [[Category: Bachmann, B O.]] |
| - | [[Category: Miller, M | + | [[Category: Miller, M T.]] |
| - | [[Category: Rosenzweig, A | + | [[Category: Rosenzweig, A C.]] |
| - | [[Category: Townsend, C | + | [[Category: Townsend, C A.]] |
[[Category: AMP]] | [[Category: AMP]] | ||
[[Category: ATP]] | [[Category: ATP]] | ||
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[[Category: deoxyguanidinoproclavaminic acid]] | [[Category: deoxyguanidinoproclavaminic acid]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:53:28 2008'' |
Revision as of 11:53, 21 February 2008
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BETA-LACTAM SYNTHETASE COMPLEXED WITH ATP
Overview
The catalytic cycle of the ATP/Mg(2+)-dependent enzyme beta-lactam synthetase (beta-LS) from Streptomyces clavuligerus has been observed through a series of x-ray crystallographic snapshots. Chemistry is initiated by the ordered binding of ATP/Mg(2+) and N(2)-(carboxyethyl)-l-arginine (CEA) to the apoenzyme. The apo and ATP/Mg(2+) structures described here, along with the previously described CEA.alpha,beta-methyleneadenosine 5'-triphosphate (CEA.AMP-CPP)/Mg(2+) structure, illuminate changes in active site geometry that favor adenylation. In addition, an acyladenylate intermediate has been trapped. The substrate analog N(2)-(carboxymethyl)-l-arginine (CMA) was adenylated by ATP in the crystal and represents a close structural analog of the previously proposed CEA-adenylate intermediate. Finally, the structure of the ternary product complex deoxyguanidinoproclavaminic acid (DGPC).AMP/PP(i)/Mg(2+) has been determined. The CMA-AMP/PP(i)/Mg(2+) and DGPC.AMP/PP(i)/Mg(2+) structures reveal interactions in the active site that facilitate beta-lactam formation. All of the ATP-bound structures differ from the previously described CEA.AMP-CPP/Mg(2+) structure in that two Mg(2+) ions are found in the active sites. These Mg(2+) ions play critical roles in both the adenylation and beta-lactamization reactions.
About this Structure
1MB9 is a Single protein structure of sequence from Streptomyces clavuligerus with , , and as ligands. Full crystallographic information is available from OCA.
Reference
The catalytic cycle of beta -lactam synthetase observed by x-ray crystallographic snapshots., Miller MT, Bachmann BO, Townsend CA, Rosenzweig AC, Proc Natl Acad Sci U S A. 2002 Nov 12;99(23):14752-7. Epub 2002 Oct 30. PMID:12409610
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