1k5q
From Proteopedia
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|PDB= 1k5q |SIZE=350|CAPTION= <scene name='initialview01'>1k5q</scene>, resolution 2.34Å | |PDB= 1k5q |SIZE=350|CAPTION= <scene name='initialview01'>1k5q</scene>, resolution 2.34Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> | + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=PAC:2-PHENYLACETIC+ACID'>PAC</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Penicillin_amidase Penicillin amidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.11 3.5.1.11] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Penicillin_amidase Penicillin amidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.11 3.5.1.11] </span> |
|GENE= PAC ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | |GENE= PAC ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1pnk|1pnk]], [[1pnl|1pnl]], [[1fxv|1fxv]], [[1jx9|1JX9]], [[1ai4|1AI4]], [[1ai5|1AI5]], [[1ai6|1AI6]], [[1ai7|1AI7]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1k5q FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1k5q OCA], [http://www.ebi.ac.uk/pdbsum/1k5q PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1k5q RCSB]</span> | ||
}} | }} | ||
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[[Category: Keizer, E.]] | [[Category: Keizer, E.]] | ||
[[Category: Snijder, H J.]] | [[Category: Snijder, H J.]] | ||
| - | [[Category: CA]] | ||
| - | [[Category: PAC]] | ||
[[Category: beta-strand]] | [[Category: beta-strand]] | ||
[[Category: helice]] | [[Category: helice]] | ||
[[Category: ntn-hydrolase fold]] | [[Category: ntn-hydrolase fold]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:43:56 2008'' |
Revision as of 18:43, 30 March 2008
| |||||||
| , resolution 2.34Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Gene: | PAC (Escherichia coli) | ||||||
| Activity: | Penicillin amidase, with EC number 3.5.1.11 | ||||||
| Related: | 1pnk, 1pnl, 1fxv, 1JX9, 1AI4, 1AI5, 1AI6, 1AI7
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
PENICILLIN ACYLASE, MUTANT COMPLEXED WITH PAA
Overview
Penicillin acylase catalyses the condensation of Calpha-substituted phenylacetic acids with beta-lactam nucleophiles, producing semi-synthetic beta-lactam antibiotics. For efficient synthesis a low affinity for phenylacetic acid and a high affinity for Calpha-substituted phenylacetic acid derivatives is desirable. We made three active site mutants, alphaF146Y, betaF24A and alphaF146Y/betaF24A, which all had a 2- to 10-fold higher affinity for Calpha-substituted compounds than wild-type enzyme. In addition, betaF24A had a 20-fold reduced affinity for phenylacetic acid. The molecular basis of the improved properties was investigated by X-ray crystallography. These studies showed that the higher affinity of alphaF146Y for (R)-alpha-methylphenylacetic acid can be explained by van der Waals interactions between alphaY146:OH and the Calpha-substituent. The betaF24A mutation causes an opening of the phenylacetic acid binding site. Only (R)-alpha-methylphenylacetic acid, but not phenylacetic acid, induces a conformation with the ligand tightly bound, explaining the weak binding of phenylacetic acid. A comparison of the betaF24A structure with other open conformations of penicillin acylase showed that betaF24 has a fixed position, whereas alphaF146 acts as a flexible lid on the binding site and reorients its position to achieve optimal substrate binding.
About this Structure
1K5Q is a Protein complex structure of sequences from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Structural and kinetic studies on ligand binding in wild-type and active-site mutants of penicillin acylase., Alkema WB, Hensgens CM, Snijder HJ, Keizer E, Dijkstra BW, Janssen DB, Protein Eng Des Sel. 2004 May;17(5):473-80. Epub 2004 Jul 14. PMID:15254299
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