1ok6: Difference between revisions

Fructose-1,6-bisphosphate aldolase (FBPA) catalyzes the reversible, cleavage of fructose 1,6-bisphosphate to glyceraldehyde 3-phosphate and, dihydroxyacetone phosphate in the glycolytic pathway. FBPAs from archaeal, organisms have recently been identified and characterized as a divergent, family of proteins. Here, we report the first crystal structure of an, archaeal FBPA at 1.9-A resolution. The structure of this 280-kDa protein, complex was determined using single wavelength anomalous dispersion, followed by 10-fold non-crystallographic symmetry averaging and refined to, an R-factor of 14.9% (Rfree 17.9%). The protein forms a dimer of, pentamers, consisting of subunits adopting the ubiquitous (betaalpha)8, barrel fold. Additionally, a crystal structure of the archaeal FBPA, covalently bound to dihydroxyacetone phosphate was solved at 2.1-A, resolution. Comparison of the active site residues with those of classical, FBPAs, which share no significant sequence identity but display the same, overall fold, reveals a common ancestry between these two families of, FBPAs. Structural comparisons, furthermore, establish an evolutionary link, to the triosephosphate isomerases, a superfamily hitherto considered, independent from the superfamily of aldolases.

1OK6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermoproteus_tenax Thermoproteus tenax] with GOL as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Fructose-bisphosphate_aldolase Fructose-bisphosphate aldolase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.2.13 4.1.2.13] Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1OK6 OCA].  

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