1b04
From Proteopedia
(New page: 200px<br /><applet load="1b04" size="450" color="white" frame="true" align="right" spinBox="true" caption="1b04, resolution 2.8Å" /> '''STRUCTURE OF THE ADEN...) |
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| - | [[Image:1b04.gif|left|200px]]<br /><applet load="1b04" size=" | + | [[Image:1b04.gif|left|200px]]<br /><applet load="1b04" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1b04, resolution 2.8Å" /> | caption="1b04, resolution 2.8Å" /> | ||
'''STRUCTURE OF THE ADENYLATION DOMAIN OF AN NAD+ DEPENDENT LIGASE'''<br /> | '''STRUCTURE OF THE ADENYLATION DOMAIN OF AN NAD+ DEPENDENT LIGASE'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: DNA ligases catalyse phosphodiester bond formation between | + | 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== | ==About this Structure== | ||
| - | 1B04 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Geobacillus_stearothermophilus Geobacillus stearothermophilus]. Active as [http://en.wikipedia.org/wiki/DNA_ligase_(NAD(+)) DNA ligase (NAD(+))], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.5.1.2 6.5.1.2] Full crystallographic information is available from [http:// | + | 1B04 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Geobacillus_stearothermophilus Geobacillus stearothermophilus]. Active as [http://en.wikipedia.org/wiki/DNA_ligase_(NAD(+)) DNA ligase (NAD(+))], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.5.1.2 6.5.1.2] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1B04 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Hakansson, K.]] | [[Category: Hakansson, K.]] | ||
| - | [[Category: Singleton, M | + | [[Category: Singleton, M R.]] |
| - | [[Category: Timson, D | + | [[Category: Timson, D J.]] |
| - | [[Category: Wigley, D | + | [[Category: Wigley, D B.]] |
[[Category: dna replication]] | [[Category: dna replication]] | ||
[[Category: ligase]] | [[Category: ligase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:50:04 2008'' |
Revision as of 09:50, 21 February 2008
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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. Active as DNA ligase (NAD(+)), with EC number 6.5.1.2 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
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