1b0i: Difference between revisions

Revision as of 10:55, 2 May 2008

ALPHA-AMYLASE FROM ALTEROMONAS HALOPLANCTIS

OverviewOverview

Background:. Enzymes from psychrophilic (cold-adapted) microorganisms operate at temperatures close to 0 degreesC, where the activity of their mesophilic and thermophilic counterparts is drastically reduced. It has generally been assumed that thermophily is associated with rigid proteins, whereas psychrophilic enzymes have a tendency to be more flexible. Results:. Insights into the cold adaptation of proteins are gained on the basis of a psychrophilic protein's molecular structure. To this end, we have determined the structure of the recombinant form of a psychrophilic alpha-amylase from Alteromonas haloplanctis at 2.4 A resolution. We have compared this with the structure of the wild-type enzyme, recently solved at 2.0 A resolution, and with available structures of their mesophilic counterparts. These comparative studies have enabled us to identify possible determinants of cold adaptation. Conclusions:. We propose that an increased resilience of the molecular surface and a less rigid protein core, with less interdomain interactions, are determining factors of the conformational flexibility that allows efficient enzyme catalysis in cold environments.

About this StructureAbout this Structure

1B0I is a Single protein structure of sequence from Pseudoalteromonas haloplanktis. Full crystallographic information is available from OCA.

ReferenceReference

Structures of the psychrophilic Alteromonas haloplanctis alpha-amylase give insights into cold adaptation at a molecular level., Aghajari N, Feller G, Gerday C, Haser R, Structure. 1998 Dec 15;6(12):1503-16. PMID:9862804 Page seeded by OCA on Fri May 2 10:55:18 2008

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

OCA

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 [[Image:1b0i.gif|left|200px]]
- {{Structure
+<!--
-|PDB= 1b0i |SIZE=350|CAPTION= <scene name='initialview01'>1b0i</scene>, resolution 2.4&Aring;
+The line below this paragraph, containing "STRUCTURE_1b0i", creates the "Structure Box" on the page.
-|SITE= <scene name='pdbsite=ACT:Active+Site'>ACT</scene>, <scene name='pdbsite=CAB:Ca+Binding+Site'>CAB</scene> and <scene name='pdbsite=CLB:Chloride+Binding+Site'>CLB</scene>
+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=CL:CHLORIDE+ION'>CL</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= AMY ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=228 Pseudoalteromonas haloplanktis])
+-->
-|DOMAIN=
+{{STRUCTURE_1b0i|  PDB=1b0i  |  SCENE=  }}
-|RELATEDENTRY=
-|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1b0i FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1b0i OCA], [http://www.ebi.ac.uk/pdbsum/1b0i PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1b0i RCSB]</span>
-}}
 '''ALPHA-AMYLASE FROM ALTEROMONAS HALOPLANCTIS'''
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 [[Category: Haser, R.]]
 [[Category: 4-glucan-4-glucanohydrolase]]
-[[Category: alpha-1]]
+[[Category: Alpha-1]]
-[[Category: alpha-amylase]]
+[[Category: Alpha-amylase]]
-[[Category: beta-alpha-eight barrel]]
+[[Category: Beta-alpha-eight barrel]]
-[[Category: psychrophilic enzyme]]
+[[Category: Psychrophilic enzyme]]
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May  2 10:55:18 2008''
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 18:51:09 2008''