| DNA N-glycosidase | <enzyme> Excises 3-methyladenine from alkylated DNA leaving an apurinic site with both 3' and 5' phosphodiester bonds intact, a preparatory step for nucleotide excision repair; excises hypoxanthine from deaminated DNA and polydeoxyribonucleotides; prefer EC 3.2.2.20 or EC 3.2.2.21 Registry number: EC 3.2.2.- Synonym: DNA glycosylase, methylpurine DNA glycosylase (26 Jun 1999) |
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| DNA, nongenetic | Through the marvellous medium of the Internet, we have discovered that DNA need not refer to deoxyribonucleic acid. Specifically, in an e-mail entitled A day in the life of a specialist registrar from Glascow, Scotland we read that in gynaecology outpatient clinic, the specialist registrar (resident in the U.S.) at 12:10 Sorted out the DNA's (did not attends). We in the U. S. Might say the no-show when a patient does not present for his/her appointment. (12 Dec 1998) |
| DNA nucleotidylexotransferase | <enzyme> A non-template-directed DNA polymerase normally found in vertebrate thymus and bone marrow. It catalyses the elongation of oligo- or polydeoxynucleotide chains and is widely used as a tool in the differential diagnosis of acute leukaemias in man. Chemical name: Nucleoside-triphosphate:DNA deoxynucleotidylexotransferase Registry number: EC 2.7.7.31 (12 Dec 1998) |
| DNA nucleotidyltransferases | <enzyme> A general term denoting enzymes that catalyze the template-directed incorporation of deoxyribonucleotides into a DNA chain. Registry number: EC 2.7.7.- (12 Dec 1998) |
| DNA photolyase | <enzyme, molecular biology> A DNA repair enzyme which recognises and removes dimers that have formed between pyrimidine nitrogenous bases on the same strand as each other, as a result of too much ultraviolet radiation. The enzyme can only do this if visible light is present. (09 Oct 1997) |
| DNA, plant | Deoxyribonucleic acid that makes up the genetic material of plants. (12 Dec 1998) |
| DNA polymerase | <enzyme, molecular biology> Enzymes involved in template directed synthesis of DNA from deoxyribonucleotide triphosphates. I, II and III are known in E. Coli, III appears to be most important in genome replication and I is important for its ability to edit out unpaired bases at the end of growing strands. Animal cells have and polymerases, with apparently responsible for replication of nuclear DNA and for replication of mitochondrial. All these function with a DNA strand as template. Retroviruses possess a unique DNA polymerase (reverse transcriptase) that uses an RNA template. (18 Nov 1997) |
| DNA polymerase beta | <enzyme> A DNA repair enzyme that catalyses DNA synthesis during base excision DNA repair. Registry number: EC 2.7.7.- (12 Dec 1998) |
| DNA polymerase i | DNA Polymerase I is an enzyme that aids in DNA replication. It has the following 3 functions: 1. Polymerizes in the 5(r) to 3(r) direction on single-stranded template. 2. Degrades single or double-stranded DNA from a free 3(r)-OH end, and 3. Degrades double-stranded DNA from a free 5(r) end. (09 Oct 1997) |
| DNA polymerase II | <enzyme> An enzyme that aids in DNA replication. It has a number of different functions, including the repair of ultraviolet radiation damaged DNA. (09 Oct 1997) |
| DNA polymerase III | <enzyme> An enzyme that aids in DNA replication. It has a number of different functions, such as: proofreading newly replicated DNA, removing nucleotides from the 3' end of the strand one by one, and binding nucleotides from the 5' end of the strand. (09 Oct 1997) |
| DNA polymerisation | <molecular biology> The making of a DNA molecule from nucleotide monomers by linking them together in a long chain (a polymer). (09 Oct 1997) |
| DNA polymorphism | A condition in which one of two different but normal nucleotide sequences can exist at a particular site in DNA. (05 Mar 2000) |
| DNA primase | <enzyme> A single-stranded DNA-dependent RNA polymerase that functions to initiate, or prime, DNA synthesis by synthesizing a nucleotide RNA polymer. Registry number: EC 2.7.7.- (12 Dec 1998) |
| DNA primers | Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques. (12 Dec 1998) |