Nucleotide analogues as probes for DNA polymerases

Transmission of the genetic information from the parental DNA strand to the offspring is crucial for the survival of any living species. In nature, all DNA synthesis in DNA replication, recombination and repair is catalyzed by DNA polymerases and depends on their ability to select the canonical nucleobase pair from a pool of structurally similar building blocks. Recently, a wealth of valuable new insights into DNA polymerase mechanisms have been gained through application of carefully designed synthetic nucleotides and oligonucleotides in functional enzyme studies. The applied analogues exhibit features that differ in certain aspects from their natural counterparts and, thus, allow investigation of the involvement and efficacy of a chosen particular aspect on the entire complex enzyme mechanism. This review will focus on a depiction of the efforts that have been undertaken towards the development of nucleotide analogues with carefully altered properties. The different approaches will be discussed in the context of the motivation and the problem under investigation.Received 16 March 2005; received after revision 5 May 2005; accepted 8 June 2005