Document Detail


The DNA scanning mechanism of T4 endonuclease V. Effect of NaCl concentration on processive nicking activity.
MedLine Citation:
PMID:  3525529     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
T4 endonuclease V is a pyrimidine dimer-specific endonuclease which generates incisions in DNA at the sites of pyrimidine dimers by a processive reaction mechanism. A model is presented in which the degree of processivity is directly related to the efficacy of the one-dimensional diffusion of endonuclease V on DNA by which the enzyme locates pyrimidine dimers. The modulation of the processive nicking activity of T4 endonuclease V on superhelical covalently closed circular DNA (form I) which contains pyrimidine dimers has been investigated as a function of the ionic strength of the reaction. Agarose gel electrophoresis was used to separate the three topological forms of the DNA which were generated in time course reactions of endonuclease V with dimer-containing form I DNA in the absence of NaCl, and in 25, 50, and 100 mM NaCl. The degree of processivity was evaluated in terms of the mass fraction of form III (linear) DNA which was produced as a function of the fraction of form I DNA remaining. Processivity is maximal in the absence of NaCl and decreases as the NaCl concentration is increased. At 100 mM NaCl, processivity is abolished and endonuclease V generates incisions in DNA at the site of dimers by a distributive reaction mechanism. The change from the distributive to a processive reaction mechanism occurs at NaCl concentrations slightly below 50 mM. The high degree of processivity which is observed in the absence of NaCl is reversible to the distributive mechanism, as demonstrated by experiments in which the NaCl concentration was increased during the time course reaction. In addition, unirradiated DNA inhibited the incision of irradiated DNA only at NaCl concentrations at which processivity was observed.
Authors:
E A Gruskin; R S Lloyd
Related Documents :
2558629 - Comparison of genomes of malignant catarrhal fever-associated herpesviruses by restrict...
23935409 - Qpso-based adaptive dna computing algorithm.
23150449 - Chip for identification of p53 responsive dna promoters.
23073289 - Visualization of the intracellular location and stability of dna origami with a label-f...
7827059 - Specific dna recognition by ecorv restriction endonuclease induced by calcium ions.
7663399 - In vitro proteolysis of endonucleases in rat liver nuclei extracts.
2797209 - Fluorescence energy transfer shows that the four-way dna junction is a right-handed cro...
22277069 - Heterogeneity and randomness of dna methylation patterns in human embryonic stem cells.
6194509 - Differential inhibition of cellular rnas by photosensitized trioxalen.
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of biological chemistry     Volume:  261     ISSN:  0021-9258     ISO Abbreviation:  J. Biol. Chem.     Publication Date:  1986 Jul 
Date Detail:
Created Date:  1986-09-17     Completed Date:  1986-09-17     Revised Date:  2012-07-04    
Medline Journal Info:
Nlm Unique ID:  2985121R     Medline TA:  J Biol Chem     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  9607-13     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
DNA / analysis*,  radiation effects
Endodeoxyribonucleases / metabolism*
Escherichia coli / enzymology
Kinetics
Osmolar Concentration
Polymers
Sodium Chloride / pharmacology*
Time Factors
Ultraviolet Rays
Grant Support
ID/Acronym/Agency:
ES 00267/ES/NIEHS NIH HHS; T32 GM 07319/GM/NIGMS NIH HHS
Chemical
Reg. No./Substance:
0/Polymers; 7647-14-5/Sodium Chloride; 9007-49-2/DNA; EC 3.1.-/Endodeoxyribonucleases; EC 3.1.21.7/deoxyribonuclease V

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Effects of insulin on lipoprotein secretion in rat hepatocyte cultures. The role of the insulin rece...
Next Document:  Cell-specific post-translational processing of preproglucagon expressed from a metallothionein-gluca...