HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Livingston, D. M. Articles by Richardson, C. C. Search for Related Content PubMed PubMed Citation Articles by Livingston, D. M. Articles by Richardson, C. C. Social Bookmarking                      What's this?

JBC, Vol. 250, Issue 2, 461-469, Jan, 1975

Deoxyribonucleic acid polymerase III of Escherichia coli. Purification and properties

D. M. Livingston, D. C. Hinkle and C. C. Richardson

DNA polymerase III has been purified 4,500-fold from the Escherichis coli mutant, HMS83, which lacks DNA polymerases I and II. When subjected to disc gel electrophoresis, the most purified fraction exhibits a single major protein band from which enzymatic activity may be recovered. Polyacrylamide gel electrophoresis under denaturing conditions produces two protein bands with molecular weights of 140,000 and 40,000. The sedimentation coefficient of the enzyme is 7.0 S, and the Stokes radius is 62 A. Taken together these tow parameters indicate a native molecular weight of 180,000. Purified DNA polymerase III catalyzes the polymerization of nucleotides into DNA when provided with both a DNA template and a complementary primer strand. The newly synthesized DNA is covalently attached to the 3' terminus of the primer strand. Because the extent of polymerization is only 10 to 100 nucleotides, the best substrates are native DNA molecules with small single-stranded regions. The most purified enzyme preparation is devoid of endonuclease activities. In addition to the two exonuclease activities described in the accompanying paper, purified polymerase III also catalyzes pyrophosphorolysis and the exchange of pyrophosphate into deoxynucleoside triphosphates. DNA polymerase III has also been isolated from wild type E. coli containing the other two known DNA polymerases. Futhermore, the enzyme purified from three different polC mutants exhibits altered polymerase III activity, confirming that polC is the structural gene for DNA polymerase III (Gefter, M., Hirota, Y., Kornberb, T., Wechsler, J., and Barnoux, C. (1971) Proc. Natl. Acad. Sci. U. S. A. 68, 3150-3153).
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				S.-W. Yang, M. Astatke, J. Potter, and D. K. Chatterjee Mutant Thermotoga neapolitana DNA polymerase I: altered catalytic properties for non-templated nucleotide addition and incorporation of correct nucleotides Nucleic Acids Res., October 1, 2002; 30(19): 4314 - 4320. [Abstract] [Full Text] [PDF]

				F C Lawyer, S Stoffel, R K Saiki, S Y Chang, P A Landre, R D Abramson, and D H Gelfand High-level expression, purification, and enzymatic characterization of full-length Thermus aquaticus DNA polymerase and a truncated form deficient in 5' to 3' exonuclease activity. Genome Res., May 1, 1993; 2(4): 275 - 287. [Abstract] [PDF]