Description
Experimental Technique/Method:X-RAY DIFFRACTION
Resolution:2.95
Classification:HYDROLASE/DNA
Release Date:2010-11-24
Deposition Date:2010-05-26
Revision Date:2011-07-13
Molecular Weight:85731.77
Macromolecule Type:Protein#DNA
Residue Count:708
Atom Site Count:6546
DOI:10.2210/pdb3n78/pdb
Abstract:
SgrAI is a type II restriction endonuclease that cuts an unusually long recognition sequence and exhibits allosteric self-activation with expansion of DNA-sequence specificity. The three-dimensional crystal structures of SgrAI bound to cleaved primary-site DNA and Mg²(+) and bound to secondary-site DNA with either Mg²(+) or Ca²(+) are presented. All three structures show a conformation of enzyme and DNA similar to the previously determined dimeric structure of SgrAI bound to uncleaved primary-site DNA and Ca²(+) [Dunten et al. (2008), Nucleic Acids Res. 36, 5405-5416], with the exception of the cleaved bond and a slight shifting of the DNA in the SgrAI/cleaved primary-site DNA/Mg²(+) structure. In addition, a new metal ion binding site is located in one of the two active sites in this structure, which is consistent with proposals for the existence of a metal-ion site near the 3'-O leaving group.
Resolution:2.95
Classification:HYDROLASE/DNA
Release Date:2010-11-24
Deposition Date:2010-05-26
Revision Date:2011-07-13
Molecular Weight:85731.77
Macromolecule Type:Protein#DNA
Residue Count:708
Atom Site Count:6546
DOI:10.2210/pdb3n78/pdb
Abstract:
SgrAI is a type II restriction endonuclease that cuts an unusually long recognition sequence and exhibits allosteric self-activation with expansion of DNA-sequence specificity. The three-dimensional crystal structures of SgrAI bound to cleaved primary-site DNA and Mg²(+) and bound to secondary-site DNA with either Mg²(+) or Ca²(+) are presented. All three structures show a conformation of enzyme and DNA similar to the previously determined dimeric structure of SgrAI bound to uncleaved primary-site DNA and Ca²(+) [Dunten et al. (2008), Nucleic Acids Res. 36, 5405-5416], with the exception of the cleaved bond and a slight shifting of the DNA in the SgrAI/cleaved primary-site DNA/Mg²(+) structure. In addition, a new metal ion binding site is located in one of the two active sites in this structure, which is consistent with proposals for the existence of a metal-ion site near the 3'-O leaving group.
| Date made available | 2010 |
|---|---|
| Publisher | RCSB-PDB |