2qua
From Proteopedia
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==Overview== | ==Overview== | ||
- | Lipase LipA from Serratia marcescens is a 613-amino acid enzyme belonging | + | Lipase LipA from Serratia marcescens is a 613-amino acid enzyme belonging to family I.3 of lipolytic enzymes that has an important biotechnological application in the production of a chiral precursor for the coronary vasodilator diltiazem. Like other family I.3 lipases, LipA is secreted by Gram-negative bacteria via a type I secretion system and possesses 13 copies of a calcium binding tandem repeat motif, GGXGXDXUX (U, hydrophobic amino acids), in the C-terminal part of the polypeptide chain. The 1.8-A crystal structure of LipA reveals a close relation to eukaryotic lipases, whereas family I.1 and I.2 enzymes appear to be more distantly related. Interestingly, the structure shows for the N-terminal lipase domain a variation on the canonical alpha/beta hydrolase fold in an open conformation, where the putative lid helix is anchored by a Ca(2+) ion essential for activity. Another novel feature observed in this lipase structure is the presence of a helical hairpin additional to the putative lid helix that exposes a hydrophobic surface to the aqueous medium and might function as an additional lid. The tandem repeats form two separated parallel beta-roll domains that pack tightly against each other. Variations of the consensus sequence of the tandem repeats within the second beta-roll result in an asymmetric Ca(2+) binding on only one side of the roll. The analysis of the properties of the beta-roll domains suggests an intramolecular chaperone function. |
==About this Structure== | ==About this Structure== | ||
- | 2QUA is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Serratia_marcescens Serratia marcescens] with <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Triacylglycerol_lipase Triacylglycerol lipase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.3 3.1.1.3] Known structural/functional Sites: <scene name='pdbsite=AC1:Ca Binding Site For Residue A 614'>AC1</scene>, <scene name='pdbsite=AC2:Ca Binding Site For Residue A 615'>AC2</scene>, <scene name='pdbsite=AC3:Ca Binding Site For Residue A 616'>AC3</scene>, <scene name='pdbsite=AC4:Ca Binding Site For Residue A 617'>AC4</scene>, <scene name='pdbsite=AC5:Ca Binding Site For Residue A 618'>AC5</scene>, <scene name='pdbsite=AC6:Ca Binding Site For Residue A 619'>AC6</scene>, <scene name='pdbsite=AC7:Ca Binding Site For Residue A 620'>AC7</scene> and <scene name='pdbsite=AC8:Ca Binding Site For Residue A 621'>AC8</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2QUA OCA]. | + | 2QUA is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Serratia_marcescens Serratia marcescens] with <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Triacylglycerol_lipase Triacylglycerol lipase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.3 3.1.1.3] Known structural/functional Sites: <scene name='pdbsite=AC1:Ca+Binding+Site+For+Residue+A+614'>AC1</scene>, <scene name='pdbsite=AC2:Ca+Binding+Site+For+Residue+A+615'>AC2</scene>, <scene name='pdbsite=AC3:Ca+Binding+Site+For+Residue+A+616'>AC3</scene>, <scene name='pdbsite=AC4:Ca+Binding+Site+For+Residue+A+617'>AC4</scene>, <scene name='pdbsite=AC5:Ca+Binding+Site+For+Residue+A+618'>AC5</scene>, <scene name='pdbsite=AC6:Ca+Binding+Site+For+Residue+A+619'>AC6</scene>, <scene name='pdbsite=AC7:Ca+Binding+Site+For+Residue+A+620'>AC7</scene> and <scene name='pdbsite=AC8:Ca+Binding+Site+For+Residue+A+621'>AC8</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2QUA OCA]. |
==Reference== | ==Reference== | ||
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[[Category: helical hairpin]] | [[Category: helical hairpin]] | ||
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:42:27 2008'' |
Revision as of 16:42, 21 February 2008
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Crystal structure of LipA from Serratia marcescens
Overview
Lipase LipA from Serratia marcescens is a 613-amino acid enzyme belonging to family I.3 of lipolytic enzymes that has an important biotechnological application in the production of a chiral precursor for the coronary vasodilator diltiazem. Like other family I.3 lipases, LipA is secreted by Gram-negative bacteria via a type I secretion system and possesses 13 copies of a calcium binding tandem repeat motif, GGXGXDXUX (U, hydrophobic amino acids), in the C-terminal part of the polypeptide chain. The 1.8-A crystal structure of LipA reveals a close relation to eukaryotic lipases, whereas family I.1 and I.2 enzymes appear to be more distantly related. Interestingly, the structure shows for the N-terminal lipase domain a variation on the canonical alpha/beta hydrolase fold in an open conformation, where the putative lid helix is anchored by a Ca(2+) ion essential for activity. Another novel feature observed in this lipase structure is the presence of a helical hairpin additional to the putative lid helix that exposes a hydrophobic surface to the aqueous medium and might function as an additional lid. The tandem repeats form two separated parallel beta-roll domains that pack tightly against each other. Variations of the consensus sequence of the tandem repeats within the second beta-roll result in an asymmetric Ca(2+) binding on only one side of the roll. The analysis of the properties of the beta-roll domains suggests an intramolecular chaperone function.
About this Structure
2QUA is a Single protein structure of sequence from Serratia marcescens with as ligand. Active as Triacylglycerol lipase, with EC number 3.1.1.3 Known structural/functional Sites: , , , , , , and . Full crystallographic information is available from OCA.
Reference
A calcium-gated lid and a large beta-roll sandwich are revealed by the crystal structure of extracellular lipase from Serratia marcescens., Meier R, Drepper T, Svensson V, Jaeger KE, Baumann U, J Biol Chem. 2007 Oct 26;282(43):31477-83. Epub 2007 Aug 28. PMID:17728256
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