2jat: Difference between revisions

Deoxyribonucleoside kinases (dNKs) catalyze the transfer of a phosphoryl, group from ATP to a deoxyribonucleoside (dN), a key step in DNA precursor, synthesis. Recently structural information concerning dNKs has been, obtained, but no structure of a bacterial dCK/dGK enzyme is known. Here we, report the structure of such an enzyme, represented by deoxyadenosine, kinase from Mycoplasma mycoides subsp. mycoides small colony type, (Mm-dAK). Superposition of Mm-dAK with its human counterpart's, deoxyguanosine kinase (dGK) and deoxycytidine kinase (dCK) reveals that, the overall structures are very similar with a few amino acid alterations, in the proximity of the active site. To investigate the substrate, specificity, Mm-dAK has been crystallized in complex with dATP and dCTP, as well as the products dCMP and dCDP. Both dATP and dCTP bind to the, enzyme in a feedback-inhibitory manner with the dN part in the, deoxyribonucleoside binding site and the triphosphates in the P-loop., Substrate specificity studies with clinically important nucleoside analogs, as well as several phosphate donors were performed. Thus, in this study we, combine structural and kinetic data to gain a better understanding of the, substrate specificity of the dCK/dGK family of enzymes. The structure of, Mm-dAK provides a starting point for making new anti bacterial agents, against pathogenic bacteria.

2JAT is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mycoplasma_mycoides_subsp._mycoides_sc Mycoplasma mycoides subsp. mycoides sc] with MG, POP and DCM as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Deoxyguanosine_kinase Deoxyguanosine kinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.113 2.7.1.113] Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2JAT OCA].  

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