4AAG: Crystal Structure Of The Mutant D75n I-Crei In Complex With Its Wild-Type Target In Presence Of Ca At The Active Site (The Four Central Bases, 2nn Region, Are Composed By Gtac From 5' To 3')

Citation:
Abstract
Homing endonucleases represent protein scaffolds that provide powerful tools for genome manipulation, as these enzymes possess a very low frequency of DNA cleavage in eukaryotic genomes due to their high specificity. The basis of protein-DNA recognition must be understood to generate tailored enzymes that target the DNA at sites of interest. Protein-DNA interaction engineering of homing endonucleases has demonstrated the potential of these approaches to create new specific instruments to target genes for inactivation or repair. Protein-DNA interface studies have been focused mostly on specific contacts between amino acid side chains and bases to redesign the binding interface. However, it has been shown that 4 bp in the central DNA sequence of the 22-bp substrate of a homing endonuclease (I-CreI), which do not show specific protein-DNA interactions, is not devoid of content information. Here, we analyze the mechanism of target discrimination in this substrate region by the I-CreI protein, determining how it can occur independently of the specific protein-DNA interactions. Our data suggest the important role of indirect readout in this substrate region, opening the possibility for a fully rational search of new target sequences, thus improving the development of redesigned enzymes for therapeutic and biotechnological applications.
PDB ID: 4AAGDownload
MMDB ID: 99217
PDB Deposition Date: 2011/12/1
Updated in MMDB: 2012/08
Experimental Method:
x-ray diffraction
Resolution: 2.8  Å
Source Organism:
synthetic construct
Similar Structures:
Biological Unit for 4AAG: tetrameric; determined by author and by software (PISA)
Molecular Components in 4AAG
Label Count Molecule
Proteins (2 molecules)
2
DNA Endonuclease I-crei
Molecule annotation
Nucleotide(1 molecule)
2
5'-d(tpcpapapapapcpgptpcpgptpapcp Gpapcpgptptptptpgpa)-3'
Molecule annotation
Chemicals (2 molecules)
1
2
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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