1e43
From Proteopedia
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| - | [[Image:1e43.gif|left|200px]] | + | [[Image:1e43.gif|left|200px]] |
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| - | '''NATIVE STRUCTURE OF CHIMAERIC AMYLASE FROM B. AMYLOLIQUEFACIENS AND B. LICHENIFORMIS AT 1.7A''' | + | {{Structure |
| + | |PDB= 1e43 |SIZE=350|CAPTION= <scene name='initialview01'>1e43</scene>, resolution 1.7Å | ||
| + | |SITE= <scene name='pdbsite=ACT:Active+Site+Residues'>ACT</scene> | ||
| + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> and <scene name='pdbligand=NA:SODIUM ION'>NA</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Alpha-amylase Alpha-amylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.1 3.2.1.1] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''NATIVE STRUCTURE OF CHIMAERIC AMYLASE FROM B. AMYLOLIQUEFACIENS AND B. LICHENIFORMIS AT 1.7A''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1E43 is a [ | + | 1E43 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_amyloliquefaciens Bacillus amyloliquefaciens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1E43 OCA]. |
==Reference== | ==Reference== | ||
| - | Structural analysis of a chimeric bacterial alpha-amylase. High-resolution analysis of native and ligand complexes., Brzozowski AM, Lawson DM, Turkenburg JP, Bisgaard-Frantzen H, Svendsen A, Borchert TV, Dauter Z, Wilson KS, Davies GJ, Biochemistry. 2000 Aug 8;39(31):9099-107. PMID:[http:// | + | Structural analysis of a chimeric bacterial alpha-amylase. High-resolution analysis of native and ligand complexes., Brzozowski AM, Lawson DM, Turkenburg JP, Bisgaard-Frantzen H, Svendsen A, Borchert TV, Dauter Z, Wilson KS, Davies GJ, Biochemistry. 2000 Aug 8;39(31):9099-107. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10924103 10924103] |
[[Category: Alpha-amylase]] | [[Category: Alpha-amylase]] | ||
[[Category: Bacillus amyloliquefaciens]] | [[Category: Bacillus amyloliquefaciens]] | ||
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[[Category: hydrolase]] | [[Category: hydrolase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 10:49:16 2008'' |
Revision as of 08:49, 20 March 2008
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| , resolution 1.7Å | |||||||
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| Sites: | |||||||
| Ligands: | and | ||||||
| Activity: | Alpha-amylase, with EC number 3.2.1.1 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
NATIVE STRUCTURE OF CHIMAERIC AMYLASE FROM B. AMYLOLIQUEFACIENS AND B. LICHENIFORMIS AT 1.7A
Overview
Several chimeric alpha-amylases genes were constructed by an in vivo recombination technique from the Bacillus amyloliquefaciens and Bacillus licheniformis genes. One of the fusion amylases (hereafter BA2), consisting of residues 1-300 from B. amyloliquefaciens and 301-483 from B. licheniformis, has been extensively studied by X-ray crystallography at resolutions between 2.2 and 1.7 A. The 3-dimensional structure of the native enzyme was solved by multiple isomorphous replacement, and refined at a resolution of 1.7 A. It consists of 483 amino acids, organized similarly to the known B. lichiniformis alpha-amylase structure [Machius et al. (1995) J. Mol. Biol. 246, 545-559], but features 4 bound calcium ions. Two of these form part of a linear cluster of three ions, the central ion being attributed to sodium. This cluster lies at the junction of the A and B domains with one calcium of the cluster structurally equivalent to the major Ca(2+) binding site of fungal alpha-amylases. The third calcium ion is found at the interface of the A and C domains. BA2 contains a fourth calcium site, not observed in the B. licheniformis alpha-amylase structure. It is found on the C domain where it bridges the two beta-sheets. Three acid residues (Glu261, Asp328, and Asp231) form an active site similar to that seen in other amylases. In the presence of TRIS buffer, a single molecule of TRIS occupies the -1 subsite of the enzyme where it is coordinated by the three active-center carboxylates. Kinetic data reveal that BA2 displays properties intermediate to those of its parents. Data for crystals soaked in maltooligosaccharides reveal the presence of a maltotriose binding site on the N-terminal face of the (beta/alpha)(8) barrel of the molecule, not previously described for any alpha-amylase structure, the biological function of which is unclear. Data for a complex soaked with the tetrasaccharide inhibitor acarbose, at 1.9 A, reveal a decasaccharide moiety, spanning the -7 to +3 subsites of the enzyme. The unambiguous presence of three unsaturated rings in the (2)H(3) half-chair/(2)E envelope conformation, adjacent to three 6-deoxypyranose units, clearly demonstrates synthesis of this acarbose-derived decasaccharide by a two-step transglycosylation mechanism.
About this Structure
1E43 is a Single protein structure of sequence from Bacillus amyloliquefaciens. Full crystallographic information is available from OCA.
Reference
Structural analysis of a chimeric bacterial alpha-amylase. High-resolution analysis of native and ligand complexes., Brzozowski AM, Lawson DM, Turkenburg JP, Bisgaard-Frantzen H, Svendsen A, Borchert TV, Dauter Z, Wilson KS, Davies GJ, Biochemistry. 2000 Aug 8;39(31):9099-107. PMID:10924103
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