1ysl: Difference between revisions

[[Image:1ysl.gif|left|200px]]<br /><applet load="1ysl" size="350" color="white" frame="true" align="right" spinBox="true"  

Biosynthesis of the isoprenoid precursor, isopentenyl diphosphate, is a critical function in all independently living organisms. There are two major pathways for this synthesis, the non-mevalonate pathway found in most eubacteria and the mevalonate pathway found in animal cells and a number of pathogenic bacteria. An early step in this pathway is the condensation of acetyl-CoA and acetoacetyl-CoA into HMG-CoA, catalyzed by the enzyme HMG-CoA synthase. To explore the possibility of a small molecule inhibitor of the enzyme functioning as a non-cell wall antibiotic, the structure of HMG-CoA synthase from Enterococcus faecalis (MVAS) was determined by selenomethionine MAD phasing to 2.4 A and the enzyme complexed with its second substrate, acetoacetyl-CoA, to 1.9 A. These structures show that HMG-CoA synthase from Enterococcus is a member of the family of thiolase fold enzymes and, while similar to the recently published HMG-CoA synthase structures from Staphylococcus aureus, exhibit significant differences in the structure of the C-terminal domain. The acetoacetyl-CoA binary structure demonstrates reduced coenzyme A and acetoacetate covalently bound to the active site cysteine through a thioester bond. This is consistent with the kinetics of the reaction that have shown acetoacetyl-CoA to be a potent inhibitor of the overall reaction, and provides a starting point in the search for a small molecule inhibitor.

1YSL is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Enterococcus_faecalis Enterococcus faecalis] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=COA:'>COA</scene>, <scene name='pdbligand=AAE:'>AAE</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Hydroxymethylglutaryl-CoA_synthase Hydroxymethylglutaryl-CoA synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.3.10 2.3.3.10] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YSL OCA].  

[[Category: II, J W.Burgner.]]

[[Category: Rodwell, V W.]]

[[Category: Stauffacher, C V.]]

[[Category: Steussy, C N.]]

[[Category: Vartia, A A.]]

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