2QXF

Product bound structure of exonuclease I at 1.5 angstrom resolution

Summary for 2QXF

• Entry DOI: 10.2210/pdb2qxf/pdb
• Descriptor: Exodeoxyribonuclease I, MAGNESIUM ION, SODIUM ION, ... (5 entities in total)
• Functional Keywords: alpha-beta domain, dnaq superfamily, sh3-like domain, product bound structure, dna damage, dna repair, exonuclease, hydrolase, nuclease
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 55904.37

Authors

Busam, R.D. (deposition date: 2007-08-11, release date: 2008-01-22, Last modification date: 2024-02-21)

Primary citation

Busam, R.D.
Structure of Escherichia coli exonuclease I in complex with thymidine 5'-monophosphate.
Acta Crystallogr.,Sect.D, 64:206-210, 2008

PubMed Abstract: In Escherichia coli, exonuclease I (ExoI) is a monomeric processive 3'-5' exonuclease that degrades single-stranded DNA. The enzyme has been implicated as primarily being involved in repairing frameshift mutations. The structure of the enzyme has previously been determined in a hexagonal space group at 2.4 A resolution. Here, the structure of ExoI in complex with a nucleotide product, thymidine 5'-monophosphate, is described in an orthorhombic space group at 1.5 A resolution. This new high-resolution structure provides some insight into the interactions involved in binding a nucleotide product. The conserved active site contains a unique metal-binding position when compared with orthologous sites in the Klenow fragment, T4 DNA polymerase and dnaQ. This unique difference is proposed to be a consequence of the repositioning of an important histidine, His181, away from the active site.

PubMed: 18219121
DOI: 10.1107/S090744490706012X

Experimental method

X-RAY DIFFRACTION (1.5 Å)