1oe0: Difference between revisions

Deoxyribonucleoside kinases are feedback inhibited by the final products, of the salvage pathway, the deoxyribonucleoside triphosphates. In the, present study, the mechanism of feedback inhibition is presented based on, the crystal structure of a complex between the fruit fly, deoxyribonucleoside kinase and its feedback inhibitor deoxythymidine, triphosphate. The inhibitor was found to be bound as a bisubstrate, inhibitor with its nucleoside part in the nucleoside binding site and with, its phosphate groups partially occupying the phosphate donor site. The, overall structure of the enzyme--inhibitor complex is very similar to the, enzyme--substrate complexes with deoxythymidine and deoxycytidine, except, for a conformational change within a region otherwise directly involved in, catalysis. This conformational change involves a magnesium ion, which is, coordinated in the inhibitor complex to the phosphates and to the primary, base, Glu52, that normally is positioned close to the 5'-OH of the, substrate deoxyribose.

1OE0 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Drosophila_melanogaster Drosophila melanogaster] with MG and TTP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Deoxynucleoside_kinase Deoxynucleoside kinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.145 2.7.1.145] Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1OE0 OCA].  

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