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1tae
From Proteopedia
Structural rearrangement accompanying NAD+ synthesis within a bacterial DNA ligase crystal
Overview
DNA ligase is an enzyme important for DNA repair and replication. Eukaryotic genomes encode ligases requiring ATP as the cofactor; bacterial genomes encode NAD(+)-dependent ligase. This difference in substrate specificities and the essentiality of NAD(+)-dependent ligase for bacterial survival make NAD(+)-dependent ligase a good target for designing highly specific anti-infectives. Any such structure-guided effort would require the knowledge of the precise mechanism of NAD+ recognition by the enzyme. We report the principles of NAD+ recognition by presenting the synthesis of NAD+ from nicotinamide mononucleotide (NMN) and AMP, catalyzed by Enterococcus faecalis ligase within the crystal lattice. Unprecedented conformational change, required to reorient the two subdomains of the protein for the condensation to occur and to recognize NAD+, is captured in two structures obtained using the same protein crystal. Structural data and sequence analysis presented here confirms and extends prior functional studies of the ligase adenylation reaction.
About this Structure
1TAE is a Single protein structure of sequence from Enterococcus faecalis v583. Full crystallographic information is available from OCA.
Reference
Structural rearrangement accompanying NAD+ synthesis within a bacterial DNA ligase crystal., Gajiwala KS, Pinko C, Structure. 2004 Aug;12(8):1449-59. PMID:15296738 Page seeded by OCA on Sat May 3 09:44:26 2008
