1b04
From Proteopedia
| |||||||
| , resolution 2.8Å | |||||||
|---|---|---|---|---|---|---|---|
| Gene: | LIG (Geobacillus stearothermophilus) | ||||||
| Activity: | DNA ligase (NAD(+)), with EC number 6.5.1.2 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE OF THE ADENYLATION DOMAIN OF AN NAD+ DEPENDENT LIGASE
Overview
BACKGROUND: DNA ligases catalyse phosphodiester bond formation between adjacent bases in nicked DNA, thereby sealing the nick. A key step in the catalytic mechanism is the formation of an adenylated DNA intermediate. The adenyl group is derived from either ATP (in eucaryotes and archaea) or NAD+4 (in bacteria). This difference in cofactor specificity suggests that DNA ligase may be a useful antibiotic target. RESULTS: The crystal structure of the adenylation domain of the NAD+-dependent DNA ligase from Bacillus stearothermophilus has been determined at 2.8 A resolution. Despite a complete lack of detectable sequence similarity, the fold of the central core of this domain shares homology with the equivalent region of ATP-dependent DNA ligases, providing strong evidence for the location of the NAD+-binding site. CONCLUSIONS: Comparison of the structure of the NAD+4-dependent DNA ligase with that of ATP-dependent ligases and mRNA-capping enzymes demonstrates the manifold utilisation of a conserved nucleotidyltransferase domain within this family of enzymes. Whilst this conserved core domain retains a common mode of nucleotide binding and activation, it is the additional domains at the N terminus and/or the C terminus that provide the alternative specificities and functionalities in the different members of this enzyme superfamily.
About this Structure
1B04 is a Single protein structure of sequence from Geobacillus stearothermophilus. Full crystallographic information is available from OCA.
Reference
Structure of the adenylation domain of an NAD+-dependent DNA ligase., Singleton MR, Hakansson K, Timson DJ, Wigley DB, Structure. 1999 Jan 15;7(1):35-42. PMID:10368271
Page seeded by OCA on Thu Mar 20 10:04:31 2008
