1fcb: Difference between revisions
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[[Image: | ==MOLECULAR STRUCTURE OF FLAVOCYTOCHROME B2 AT 2.4 ANGSTROMS RESOLUTION== | ||
<StructureSection load='1fcb' size='340' side='right' caption='[[1fcb]], [[Resolution|resolution]] 2.40Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1fcb]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1FCB OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1FCB FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=FMN:FLAVIN+MONONUCLEOTIDE'>FMN</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=PYR:PYRUVIC+ACID'>PYR</scene><br> | |||
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/L-lactate_dehydrogenase_(cytochrome) L-lactate dehydrogenase (cytochrome)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.2.3 1.1.2.3] </span></td></tr> | |||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1fcb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1fcb OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1fcb RCSB], [http://www.ebi.ac.uk/pdbsum/1fcb PDBsum]</span></td></tr> | |||
<table> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fc/1fcb_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The crystal structure of flavocytochrome b2 has been solved at 3.0 A resolution by the method of multiple isomorphous replacement with anomalous scattering. Area detector data from native and two heavy-atom derivative crystals were used. The phases were refined by the B.C. Wang phase-filtering procedure utilizing the 67% (v/v) solvent content of the crystals. A molecular model was built first on a minimap and then on computer graphics from a combination of maps both averaged and not averaged about the molecular symmetry axis. The structure was extended to 2.4 A resolution using film data recorded at a synchrotron and refined by the Hendrickson-Konnert procedure. The molecule, a tetramer of Mr 230,000, is located on a crystallographic 2-fold axis and possesses local 4-fold symmetry. Each subunit is composed of two domains, one binding a heme and the other an FMN prosthetic group. In subunit 1, both the cystochrome and the flavin-binding domain are visible in the electron density map. In subunit 2 the cytochrome domain is disordered. However, in the latter, a molecule of pyruvate, the product of the enzymatic reaction, is bound at the active site. The cytochrome domain consists of residues 1 to 99 and is folded in a fashion similar to the homologous soluble fragment of cytochrome b5. The flavin binding domain contains a parallel beta 8 alpha 8 barrel structure and is composed of residues 100 to 486. The remaining 25 residues form a tail that wraps around the molecular 4-fold axis and is in contact with each remaining subunit. The FMN moiety, which is located at the C-terminal end of the central beta-barrel, is mostly sequestered from solvent; it forms hydrogen bond interactions with main- and side-chain atoms from six of the eight beta-strands. The interaction of Lys349 with atoms N-1 and O-2 of the flavin ring is probably responsible for stabilization of the anionic form of the flavin semiquinone and hydroquinone and enhancing the reactivity of atom N-5 toward sulfite. The binding of pyruvate at the active site in subunit 2 is stabilized by interaction of its carboxylate group with the side-chain atoms of Arg376 and Tyr143. Residues His373 and Tyr254 interact with the keto-oxygen atom and are involved in catalysis. In contrast, four water molecules occupy the substrate-binding site in subunit 1 and Tyr143 forms a hydrogen bond to the ordered heme propionate group. Otherwise the two flavin-binding domains are identical within experimental error.(ABSTRACT TRUNCATED AT 400 WORDS) | |||
Molecular structure of flavocytochrome b2 at 2.4 A resolution.,Xia ZX, Mathews FS J Mol Biol. 1990 Apr 20;212(4):837-63. PMID:2329585<ref>PMID:2329585</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
*[[Flavocytochrome|Flavocytochrome]] | *[[Flavocytochrome|Flavocytochrome]] | ||
== References == | |||
== | <references/> | ||
< | __TOC__ | ||
</StructureSection> | |||
[[Category: Saccharomyces cerevisiae]] | [[Category: Saccharomyces cerevisiae]] | ||
[[Category: Mathews, F S.]] | [[Category: Mathews, F S.]] | ||
[[Category: Xia, Z X.]] | [[Category: Xia, Z X.]] | ||
