Methods in Molecular Biology • 16 Enzymes of Molecular Biology

CHAPTER 3

DNA Polymerases (EC 2.7.7.7)

Martin J. Maunders

1. Introduction
   DNA polymerases catalyze the synthesis of DNA molecules from
   monomeric deoxynucleotide triphosphate units. This definition encom-
   passes those enzymes classed as DNA-dependent DNA polymerases
   (EC 2.7.7.7, which require both a DNA template strand and a DNA
   primer to which the monomeric units can be added), reverse tran-
   scriptases (EC 2.7.7.49, RNA-dependent DNA polymerases that uti-
   lize an RNA template), and terminal deoxynucleotidyl transferases
   (EC 2.7.7.31, which require no template). This chapter will consider
   only DNA-dependent DNA polymerases (EC 2.7.7.7, DNA
   nucleotidyltransferases, DNA-directed).
   DNA-dependent DNA polymerases are a class of enzyme that is
   essential for the replication and maintenance of all organisms. All
   perform essentially the same reaction, the addition of monomeric units
   to synthesize a complementary copy of an existing DNA template.
   This activity can be used in molecular biology for a wide range of
   techniques. These include the labeling of DNA molecules, terminally
   or throughout the sequence, for use as probes or for sequence determi-
   nation, the modification of DNA termini for facilitating subsequent
   manipulations, the production of double-stranded cDNA, the exten-
   sion of mismatched sequences for site-directed mutagenesis, the exten-
   sion of synthetic DNA sequences for gene synthesis, and the specific
   amplification of limiting quantities of DNA for analysis.

From: Methods in Molecular Biology, Vol. 16: Enzymes of Molecular Biology

Edited by: M. M. Burrell Copyright ©1993 Humana Press Inc., Totowa, NJ

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