Nucleic Acids Research Advance Access originally published online on August 20, 2007
Nucleic Acids Research 2007 35(17):5635-5645; doi:10.1093/nar/gkm625
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Nucleic Acids Research, 2007, Vol. 35, No. 17 5635-5645
© 2007 The Author(s)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Nucleic Acid Enzymes |
Properties of an unusual DNA primase from an archaeal plasmid
Institute of Biochemistry, University of Bayreuth, Universitätstrasse 30, 95447 Bayreuth, Germany
*To whom correspondence should be addressed. Tel: ++49 921 552433; Fax: ++49 921 552432; Email: georg.lipps{at}uni-bayreuth.de
Received July 4, 2007. Revised July 30, 2007. Accepted July 30, 2007.
Primases are specialized DNA-dependent RNA polymerases that synthesize a short oligoribonucleotide complementary to single-stranded template DNA. In the context of cellular DNA replication, primases are indispensable since DNA polymerases are not able to start DNA polymerization de novo.
The primase activity of the replication protein from the archaeal plasmid pRN1 synthesizes a rather unusual mixed primer consisting of a single ribonucleotide at the 5' end followed by seven deoxynucleotides. Ribonucleotides and deoxynucleotides are strictly required at the respective positions within the primer. Furthermore, in contrast to other archaeo-eukaryotic primases, the primase activity is highly sequence-specific and requires the trinucleotide motif GTG in the template. Primer synthesis starts outside of the recognition motif, immediately 5' to the recognition motif. The fidelity of the primase synthesis is high, as non-complementary bases are not incorporated into the primer.