From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:1amy.jpg|left|200px]] | + | {{Seed}} |
| | + | [[Image:1amy.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 9: |
Line 10: |
| | {{STRUCTURE_1amy| PDB=1amy | SCENE= }} | | {{STRUCTURE_1amy| PDB=1amy | SCENE= }} |
| | | | |
| - | '''CRYSTAL AND MOLECULAR STRUCTURE OF BARLEY ALPHA-AMYLASE'''
| + | ===CRYSTAL AND MOLECULAR STRUCTURE OF BARLEY ALPHA-AMYLASE=== |
| | | | |
| | | | |
| - | ==Overview==
| + | <!-- |
| - | The three-dimensional structure of barley malt alpha-amylase (isoform AMY2-2) was determined by multiple isomorphous replacement using three heavy-atom derivatives and solvent flattening. The model was refined using a combination of simulated annealing and conventional restrained least-squares crystallographic refinement to an R-factor of 0.153 based on 18,303 independent reflections with F(o) > sigma(F(o)) between 10 and 2.8 A resolution, with root-mean-square deviations of 0.016 A and 3.3 degrees from ideal bond lengths and bond angles, respectively. The final model consists of 403 amino acid residues, three calcium ions and 153 water molecules. The polypeptide chain folds into three domains: a central domain forming a (beta alpha)8-barrel of 286 residues, with a protruding irregular structured loop domain of 64 residues (domain B) connecting strand beta 3 and helix alpha 3 of the barrel, and a C-terminal domain of 53 residues forming a five stranded anti-parallel beta-sheet. Unlike the previously known alpha-amylase structures, AMY2-2 contains three Ca2+ binding sites co-ordinated by seven or eight oxygen atoms from carboxylate groups, main-chain carbonyl atoms and water molecules, all calcium ions being bound to domain B and therefore essential for the structural integrity of that domain. Two of the Ca2+ sites are located only 7.0 A apart with one Asp residue serving as ligand for both. One Ca2+ site located at about 20 A from the other two was found to be exchangeable with Eu3+. By homology with other alpha-amylases, some important active site residues are identified as Asp179, Glu204 and Asp289, and are situated at the C-terminal end of the central beta-barrel. A starch granule binding site, previously identified as Trp276 and Trp277, is situated on alpha-helix 6 in the central (beta alpha)8-barrel, at the surface of the enzyme. This binding site region is associated with a considerable disruption of the (beta alpha)8-barrel 8-fold symmetry.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_8196040}}, adds the Publication Abstract to the page |
| | + | (as it appears on PubMed at http://www.pubmed.gov), where 8196040 is the PubMed ID number. |
| | + | --> |
| | + | {{ABSTRACT_PUBMED_8196040}} |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| Line 25: |
Line 29: |
| | [[Category: Haser, R.]] | | [[Category: Haser, R.]] |
| | [[Category: Kadziola, A.]] | | [[Category: Kadziola, A.]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 10:27:55 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jun 30 17:11:28 2008'' |
Revision as of 14:11, 30 June 2008
Template:STRUCTURE 1amy
CRYSTAL AND MOLECULAR STRUCTURE OF BARLEY ALPHA-AMYLASE
Template:ABSTRACT PUBMED 8196040
About this Structure
1AMY is a Single protein structure of sequence from Hordeum vulgare. Full crystallographic information is available from OCA.
Reference
Crystal and molecular structure of barley alpha-amylase., Kadziola A, Abe J, Svensson B, Haser R, J Mol Biol. 1994 May 27;239(1):104-21. PMID:8196040
Page seeded by OCA on Mon Jun 30 17:11:28 2008
