Anthony Noles Sandbox: Difference between revisions

The <scene name='Anthony_Noles_Sandbox/Secondary_structure/1'>secondary structure</scene> consists of numerous alternating alpha helices and beta sheets (SCOP classification α/β alternating). The tertiary structure is somewhat bilobed with the active site in the middle, and, since there is only one subunit, there is no quaternary structure. Aconitase consists of four domains, three of which are tightly packed while the fourth is more flexible. <ref name="Frishman">Frishman, D., and Hentze, M.W., "Conservation of aconitase residues revealed by multiple sequence analysis: Implications for structure/function relationships." European Journal of Biochemistry, 1996, 239, 197-200.</ref> Aconitase contains a <scene name='Anthony_Noles_Sandbox/Fe-scluster/2'>4Fe-4S iron-sulfur cluster</scene>. This iron sulfur cluster does not participate in redox as most do, but holds the OH goup of citrate to facilitate its elimination.<ref>PMID:16407072 </ref> It is at this 4Fe-4S site that catalysis occurs and citrate or <scene name='Anthony_Noles_Sandbox/Fe-scluster_bound_isocitrate/8'>isocitrate</scene> is bound. The rest of the <scene name='Anthony_Noles_Sandbox/Fe-scluster_w_active_site/4'>active site (manually rotate scene to see residue proximity to the 4Fe-4S cluster</scene> is made up of residues Gln72, Asp100, His101, Asp165, Ser166, His167, His147, Glu262, Asn258, Cys358, Cys421, Cys424, Cys358, Cys421, Asn446, Arg447, Arg452, Asp568, Ser642, Ser643, Arg644, Arg580. <ref name="Beinert">Beinert, H., Kennedy, M. C., Stout, C.D. “Aconitase as Iron−Sulfur Protein, Enzyme, and Iron-Regulatory Protein.” Chem. Rev. 1996, 96, 2335−2373.</ref>