nucleotidepolymorfismen

Nucleotide polymerase refers to enzymes that catalyze the formation of nucleic acid polymers by linking nucleotides through phosphodiester bonds. In most cases, these enzymes extend a growing strand by adding nucleoside triphosphates to a primer or existing chain, releasing pyrophosphate in the process. Most require divalent metal ions, typically magnesium, to coordinate substrates and activate the 3' hydroxyl group for nucleophilic attack on the incoming nucleotide.

The best-known nucleotide polymerases are DNA polymerases, which replicate the genome, and RNA polymerases, which transcribe RNA from a DNA template. There are also reverse transcriptases that synthesize DNA from RNA templates. Polymerases vary in their fidelity and processivity; some possess 3' to 5' exonuclease proofreading activity that improves accuracy, while others lack proofreading. They are organized into several structural families, reflecting their evolutionary origins and functional specializations, and they operate in different cellular compartments and contexts.

Biological roles of nucleotide polymerases include genome replication, transcription of genes, DNA repair, and genetic recombination. They interact with a range of accessory factors and are tightly regulated to ensure proper timing and accuracy of nucleic acid synthesis. Mutations or inhibition of polymerases can have profound effects on cell viability and genome integrity.

Nucleotide polymerases have significant pharmacological and biotechnological relevance. Antiviral and anticancer therapies often target polymerases or use nucleotide analogs to terminate elongation. In biotechnology, thermostable DNA polymerases such as Taq and high-fidelity options enable polymerase chain reaction and other molecular biology techniques, underpinning modern genetics and diagnostics. The discovery and study of DNA polymerase I by Arthur Kornberg in 1956 marked a foundational milestone in molecular biology.