Imperial College London
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ProfessorPaulFreemont

Faculty of Medicine, Department of Infectious Disease

Chair in Protein Crystallography
 
 
 
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Contact

 

+44 (0)20 7594 5327p.freemont

 
 
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Location

 

259Sir Alexander Fleming BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@inbook{Freemont:2020,
author = {Freemont, PS and Friedman, JM and Beese, LS and Sanderson, MR and Steitz, TA},
booktitle = {Structural Insights into Gene Expression and Protein Synthesis},
pages = {240--244},
title = {Cocrystal structure of an editing complex of klenow fragment with dna (3'-5' exonuclease dna polymerase protein-dna interaction x-ray crystallography/metal ion catalysis)},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - CHAP
AB  - High-resolution crystal structures of editing complexes of both duplex and single-stranded DNA bound to Escherichia coli DNA polymerase I large fragment (Klenow fragment) show four nucleotides of single-stranded DNA bound to the 3′ – 5′ exonuclease active site and extending toward the polymerase active site. Melting of the duplex DNA by the protein is stabilized by hydophobic interactions between Phe-473, Leu-361, and His-666 and the last three bases at the 3′ terminus. Two divalent metal ions interacting with the phosphodiester to be hydrolyzed are proposed to catalyze the exonuclease reaction by a mechanism that may be related to mechanisms of other enzymes that catalyze phospho-group transfer including RNA enzymes. We suggest that the editing active site competes with the polymerase active site some 30 Å away for the newly formed 3′ terminus. Since a 3′ terminal mismatched base pair favors the melting of duplex DNA, its binding and excision at the editing exonuclease site that binds single-stranded DNA is enhanced.
AU  - Freemont,PS
AU  - Friedman,JM
AU  - Beese,LS
AU  - Sanderson,MR
AU  - Steitz,TA
EP  - 244
PY  - 2020///
SN  - 9789811215858
SP  - 240
TI  - Cocrystal structure of an editing complex of klenow fragment with dna (3'-5' exonuclease dna polymerase protein-dna interaction x-ray crystallography/metal ion catalysis)
T1  - Structural Insights into Gene Expression and Protein Synthesis
ER  -
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