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Found DNA repair 7 times.

Displaying results 1 to 10.

1. DNA excision
The removal of a damaged segment of a DNA molecule by a group of DNA repair enzyme s in order to repair the molecule.

2. DNA glycosylase
A DNA repair enzyme which recognizes and removes nitrogenous base s in the DNA molecule that have lost an amino group , leaving a hole that then undergoes further repair.

3. DNA photolyase (photoreactivating enzyme)
A DNA repair enzyme which recognizes and removes dimer s that have formed between pyrimidine nitrogenous base s 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.

4. DNA repair
Any of a number of processes to repair damaged DNA . In general, the damaged portions of the molecule are removed by enzyme s (this could range from a single nitrogenous base to a large number of them, and the enzymes doing the removing depend on the specific type of damage), leaving holes where bases should be. Then other enzymes remove an entire segment of DNA, in the middle of which was the hole or holes. A DNA polymerase I then comes and fills the gap with new nitrogenous bases, based on what bases are on the opposite (presumably unharmed) strand of DNA (if both strands are harmed, a process is invoked which inserts bases at random into the strand). Finally a ligase enzyme seals the phosphate backbone back together.

5. Error-prone repair (SOS repair)
A type of DNA repair which occurs when both nucleotide s in a base pair are missing, such that it is not possible to maintain accuracy. In general, the repair protein s replace the missing nucleotides randomly. The idea is that "bad" DNA is better than no DNA at all.

6. Excision repair
A DNA repair process where the damaged portion of DNA is excised, or removed, then the removed part is recopied from the other undamaged strand by DNA polymerase enzyme s, and finally the replacement part is attached to the site by DNA ligase enzymes.

7. Photoreactivation (light repair)
The repair of DNA that has been damaged by ultraviolet radiation , by the DNA repair enzyme photolyase , which requires the presence of visible light .

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