1hvx: Difference between revisions

Revision as of 19:17, 2 May 2008

BACILLUS STEAROTHERMOPHILUS ALPHA-AMYLASE

OverviewOverview

The crystal structure of a thermostable alpha-amylase from Bacillus stearothermophilus (BSTA) has been determined at 2.0 A resolution. The main-chain fold is almost identical to that of the known crystal structure of Bacillus licheniformis alpha-amylase (BLA). BLA is known to be more stable than BSTA. A structural comparison between the crystal structures of BSTA and BLA showed significant differences that may account for the difference in their thermostabilities, as follows. (i) The two-residue insertion in BSTA, Ile181-Gly182, pushes away the spatially contacting region including Asp207, which corresponds to Ca(2+)-coordinating Asp204 in BLA. As a result, Asp207 cannot coordinate the Ca(2+). (ii) BSTA contains nine fewer hydrogen bonds than BLA, which costs about 12 kcal/mol. This tendency is prominent in the (beta/alpha)(8)-barrel, where 10 fewer hydrogen bonds were observed in BSTA. BLA forms a denser hydrogen bond network in the inter-helical region, which may stabilize alpha-helices in the barrel. (iii) A few small voids observed in the alpha-helical region of the (beta/alpha)(8)-barrel in BSTA decrease inter-helical compactness and hydrophobic interactions. (iv) The solvent-accessible surface area of charged residues in BLA is about two times larger than that in BSTA.

About this StructureAbout this Structure

1HVX is a Single protein structure of sequence from Geobacillus stearothermophilus. Full crystallographic information is available from OCA.

ReferenceReference

Crystal structure of Bacillus stearothermophilus alpha-amylase: possible factors determining the thermostability., Suvd D, Fujimoto Z, Takase K, Matsumura M, Mizuno H, J Biochem. 2001 Mar;129(3):461-8. PMID:11226887 Page seeded by OCA on Fri May 2 19:17:03 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

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 [[Image:1hvx.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1hvx |SIZE=350|CAPTION= <scene name='initialview01'>1hvx</scene>, resolution 2.0&Aring;
+The line below this paragraph, containing "STRUCTURE_1hvx", creates the "Structure Box" on the page.
-|SITE=
+You may change the PDB parameter (which sets the PDB file loaded into the applet)
-|LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>
+or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
-|ACTIVITY= <span class='plainlinks'>[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] </span>
+or leave the SCENE parameter empty for the default display.
-|GENE= AMYT631 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1422 Geobacillus stearothermophilus])
+-->
-|DOMAIN=
+{{STRUCTURE_1hvx|  PDB=1hvx  |  SCENE=  }}
-|RELATEDENTRY=
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1hvx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1hvx OCA], [http://www.ebi.ac.uk/pdbsum/1hvx PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1hvx RCSB]</span>
-}}
 '''BACILLUS STEAROTHERMOPHILUS ALPHA-AMYLASE'''
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 [[Category: Suvd, D.]]
 [[Category: Takase, K.]]
-[[Category: alpha-1,4-glucan-4-glucanohydrolase]]
+[[Category: Alpha-1,4-glucan-4-glucanohydrolase]]
-[[Category: alpha-amylase,starch degradation]]
+[[Category: Alpha-amylase,starch degradation]]
-[[Category: calcium]]
+[[Category: Calcium]]
-[[Category: glycosyltransferase]]
+[[Category: Glycosyltransferase]]
-[[Category: hydrolase]]
+[[Category: Hydrolase]]
-[[Category: sodium]]
+[[Category: Sodium]]
-[[Category: thermostability]]
+[[Category: Thermostability]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May  2 19:17:03 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:11:09 2008''