Enzymological Characterization of Human DNA Polymerases-α and β

1983 ◽  
pp. 17-55 ◽  
Author(s):  
David Korn ◽  
Paul A. Fisher ◽  
Teresa Shu-Fong Wang
Keyword(s):  
Dna Polymerases ◽  
Human Dna

Detection and characterization of DNA polymerase activity in Toxoplasma gondii

Parasitology ◽  
1993 ◽  
Vol 107 (2) ◽  
pp. 135-139 ◽  
Author(s):  
A. Makioka ◽  
B. Stavros ◽  
J. T. Ellis ◽  
A. M. Johnson
Keyword(s):  
Toxoplasma Gondii ◽  
Dna Polymerase ◽  
Dna Polymerases ◽  
Sedimentation Coefficient ◽  
Polymerase Activity ◽  
Magnesium Ions ◽  
Dna Polymerase Β ◽  
Human Dna ◽  
Approximate Molecular Weight

SUMMARYA DNA polymerase activity has been detected and characterized in crude extracts from tachzoites of Toxoplasma gondii. The enzyme has a sedimentation coefficient of 6·4 S, corresponding to an approximate molecular weight of 150000 assuming a globular shape. Like mammalian DNA polymerase α, the DNA polymerase of T. gondii was sensitive to N-ethylmaleimide and inhibited by high ionic strength. However, the enzyme activity was not inhibited by aphidicolin which is an inhibitor of mammalian DNA polymerases α, δ and ε and also cytosine-β-D-arabinofuranoside-5′-triphosphate which is an inhibitor of α polymerase. The activity was inhibited by 2′,3′-dideoxythymidine-5′-triphosphate which is an inhibitor of mammalian DNA polymerase β and γ. Magnesium ions (Mg2+) were absolutely required for activity and its optimal concentration was 6 mM. The optimum potassium (K+) concentration was 50 mM and a higher concentration of K+ markedly inhibited the activity. Activity was optimal at pH 8. Monoclonal antibodies against human DNA polymerase did not bind to DNA polymerase of T. gondii. Thus the T. gondii enzyme differs from the human enzymes and may be a useful target for the design of toxoplasmacidal drugs.

scholarly journals A real-time fluorescence method for enzymatic characterization of specialized human DNA polymerases

2009 ◽  
Vol 37 (19) ◽  
pp. e128-e128 ◽  
Author(s):  
Dorjbal Dorjsuren ◽  
David M. Wilson ◽  
William A. Beard ◽  
John P. McDonald ◽  
Christopher P. Austin ◽  
...  
Keyword(s):  
Real Time ◽  
Dna Polymerases ◽  
Fluorescence Method ◽  
Enzymatic Characterization ◽  
Human Dna

Characterization of a novel inhibitor of human DNA polymerases: 3,4,5-tri-O-galloylquinic acid

1989 ◽  
Vol 38 (21) ◽  
pp. 3759-3765 ◽  
Author(s):  
William B. Parker ◽  
Makoto Nishizawa ◽  
Michael H. Fisher ◽  
Ning Ye ◽  
Kuo-Hsiung Lee ◽  
...  
Keyword(s):  
Dna Polymerases ◽  
Human Dna

scholarly journals Molecular and structural characterization of oxidized ribonucleotide insertion into DNA by human DNA polymerase β

2019 ◽  
Vol 295 (6) ◽  
pp. 1613-1622
Author(s):  
Mallory R. Smith ◽  
Khadijeh S. Alnajjar ◽  
Nicole M. Hoitsma ◽  
Joann B. Sweasy ◽  
Bret D. Freudenthal
Keyword(s):  
Dna Polymerase ◽  
Conformational Changes ◽  
Dna Polymerases ◽  
Catalytic Efficiency ◽  
Dna Polymerase Β ◽  
Replication Errors ◽  
Human Dna ◽  
Oxidatively Modified ◽  
Dna Replication Errors

During oxidative stress, inflammation, or environmental exposure, ribo- and deoxyribonucleotides are oxidatively modified. 8-Oxo-7,8-dihydro-2′-guanosine (8-oxo-G) is a common oxidized nucleobase whose deoxyribonucleotide form, 8-oxo-dGTP, has been widely studied and demonstrated to be a mutagenic substrate for DNA polymerases. Guanine ribonucleotides are analogously oxidized to r8-oxo-GTP, which can constitute up to 5% of the rGTP pool. Because ribonucleotides are commonly misinserted into DNA, and 8-oxo-G causes replication errors, we were motivated to investigate how the oxidized ribonucleotide is utilized by DNA polymerases. To do this, here we employed human DNA polymerase β (pol β) and characterized r8-oxo-GTP insertion with DNA substrates containing either a templating cytosine (nonmutagenic) or adenine (mutagenic). Our results show that pol β has a diminished catalytic efficiency for r8-oxo-GTP compared with canonical deoxyribonucleotides but that r8-oxo-GTP is inserted mutagenically at a rate similar to those of other common DNA replication errors (i.e. ribonucleotide and mismatch insertions). Using FRET assays to monitor conformational changes of pol β with r8-oxo-GTP, we demonstrate impaired pol β closure that correlates with a reduced insertion efficiency. X-ray crystallographic analyses revealed that, similar to 8-oxo-dGTP, r8-oxo-GTP adopts an anti conformation opposite a templating cytosine and a syn conformation opposite adenine. However, unlike 8-oxo-dGTP, r8-oxo-GTP did not form a planar base pair with either templating base. These results suggest that r8-oxo-GTP is a potential mutagenic substrate for DNA polymerases and provide structural insights into how r8-oxo-GTP is processed by DNA polymerases.

Template Dependent Human DNA Polymerases

2008 ◽  
Vol 8 (15) ◽  
pp. 1312-1326 ◽  
Author(s):  
Luis Brieba
Keyword(s):  
Dna Polymerases ◽  
Human Dna

scholarly journals Characterization of a human DNA damage binding protein implicated in xeroderma pigmentosum E.

1993 ◽  
Vol 268 (28) ◽  
pp. 21293-21300
Author(s):  
S Keeney ◽  
G.J. Chang ◽  
S Linn
Keyword(s):  
Dna Damage ◽  
Xeroderma Pigmentosum ◽  
Binding Protein ◽  
Human Dna

Characterization of the human DNA gut virome across populations with different subsistence strategies and geographical origin

2017 ◽  
Vol 19 (11) ◽  
pp. 4728-4735 ◽  
Author(s):  
Simone Rampelli ◽  
Silvia Turroni ◽  
Stephanie L. Schnorr ◽  
Matteo Soverini ◽  
Sara Quercia ◽  
...  
Keyword(s):  
Geographical Origin ◽  
Subsistence Strategies ◽  
Human Dna

Characterization of a panel of highly variable minisatellites cloned from human DNA

1987 ◽  
Vol 51 (4) ◽  
pp. 269-288 ◽  
Author(s):  
Z. WONG ◽  
V. WILSON ◽  
I. PATEL ◽  
S. POVEY ◽  
A. J. JEFFREYS
Keyword(s):  
Human Dna
Sign in / Sign up

Export Citation Format

Share Document