News & Notes: Primary Structure of the DNA Polymerase I Gene of an α-Proteobacterium, Rhizobium leguminosarum, and Comparison with Other Family A DNA Polymerases

1999 ◽  
Vol 38 (6) ◽  
pp. 355-359 ◽  
Author(s):  
Yi-Ping Huang ◽  
J. Allan Downie ◽  
Junetsu Ito
Keyword(s):  
Dna Polymerase ◽  
Primary Structure ◽  
Rhizobium Leguminosarum ◽  
Dna Polymerases ◽  
Dna Polymerase I ◽  
Polymerase I ◽  
I Gene

Inhibition by Cyclic Guanosine 3':5'-Monophosphate of the Soluble DNA Polymerase Activity, and of Partially Purified DNA Polymerase A (DNA Polymerase I) from the Yeast Saccharomyces cerevisiae

1981 ◽  
Vol 36 (9-10) ◽  
pp. 813-819 ◽  
Author(s):  
Hans Eckstein
Keyword(s):  
Dna Polymerase ◽  
Dna Polymerases ◽  
Nuclease Activity ◽  
Polymerase Activity ◽  
Yeast Cells ◽  
Primer Binding Site ◽  
Dna Polymerase I ◽  
Yeast Saccharomyces Cerevisiae ◽  
Main Component ◽  
Polymerase I

Abstract Dedicated to Professor Dr. Joachim Kühnau on the Occasion of His 80th Birthday cGMP, DNA Polymerase Activity, DNA Polymerase A, DNA Polymerase I, Baker's Yeast DNA polymerase activity from extracts of growing yeast cells is inhibited by cGMP. Experiments with partially purified yeast DNA polymerases show, that cGMP inhibits DNA polymerase A (DNA polymerase I from Chang), which is the main component of the soluble DNA polymerase activity in yeast extracts, by competing for the enzyme with the primer-template DNA. Since the enzyme is not only inhibited by 3',5'-cGMP, but also by 3',5'-cAMP, the 3': 5'-phosphodiester seems to be crucial for the competition between cGMP and primer. This would be inconsistent with the concept of a 3'-OH primer binding site in the enzyme. The existence of such a site in the yeast DNA polymerase A is indicated from studies with various purine nucleoside monophosphates.When various DNA polymerases are compared, inhibition by cGMP seems to be restricted to those enzymes, which are involved in DNA replication. DNA polymerases with an associated nuclease activity are not inhibited, DNA polymerase B from yeast is even activated by cGMP. Though some relations between the cGMP effect and the presumed function of the enzymes in the living cell are apparent, the biological meaning of the observations in general remains open.

scholarly journals Polymerization activity of an alpha-like DNA polymerase requires a conserved 3'-5' exonuclease active site

1991 ◽  
Vol 11 (9) ◽  
pp. 4786-4795
Author(s):  
J S Gibbs ◽  
K Weisshart ◽  
P Digard ◽  
A deBruynKops ◽  
D M Knipe ◽  
...  
Keyword(s):  
Dna Polymerase ◽  
Active Site ◽  
Dna Polymerases ◽  
Polymerase Activity ◽  
Cell Nuclei ◽  
Dna Polymerase I ◽  
Viral Dna ◽  
Gene Encoding ◽  
Simplex Virus ◽  
Polymerase I

Most DNA polymerases are multifunctional proteins that possess both polymerizing and exonucleolytic activities. For Escherichia coli DNA polymerase I and its relatives, polymerase and exonuclease activities reside on distinct, separable domains of the same polypeptide. The catalytic subunits of the alpha-like DNA polymerase family share regions of sequence homology with the 3'-5' exonuclease active site of DNA polymerase I; in certain alpha-like DNA polymerases, these regions of homology have been shown to be important for exonuclease activity. This finding has led to the hypothesis that alpha-like DNA polymerases also contain a distinct 3'-5' exonuclease domain. We have introduced conservative substitutions into a 3'-5' exonuclease active site homology in the gene encoding herpes simplex virus DNA polymerase, an alpha-like polymerase. Two mutants were severely impaired for viral DNA replication and polymerase activity. The mutants were not detectably affected in the ability of the polymerase to interact with its accessory protein, UL42, or to colocalize in infected cell nuclei with the major viral DNA-binding protein, ICP8, suggesting that the mutation did not exert global effects on protein folding. The results raise the possibility that there is a fundamental difference between alpha-like DNA polymerases and E. coli DNA polymerase I, with less distinction between 3'-5' exonuclease and polymerase functions in alpha-like DNA polymerases.

THE PRIMARY STRUCTURE OF DNA POLYMERASE I OF E. COLI

1980 ◽  
pp. 589-596
Author(s):  
Catherine M. Joyce ◽  
William S. Kelley ◽  
William E. Brown ◽  
Nigel D.F. Grindley
Keyword(s):  
Dna Polymerase ◽  
Primary Structure ◽  
Dna Polymerase I ◽  
E Coli ◽  
Polymerase I
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