Table 1.

DNA repair systems that address UV-induced damage, all of which have been researched in halophilic archaea, ^∗with the exception of single-strand break repair.

Repair mechanism	UV photodamage repaired
Photoreactivation	Cyclobutane pyrimidine dimers,
	Pyrimidine (6-4) pyrimidone photoproducts
	Dewar isomers
Nucleotide excision repair	Cyclobutane pyrimidine dimers
(Sub-category: transcription-coupled repair)	Pyrimidine (6-4) pyrimidone photoproducts
	Dewar isomers
Base excision repair	Oxidative base lesions
	Single-strand breaks∗
Homologous recombination	Double-strand breaks
	Cyclobutane pyrimidine dimers
	Pyrimidine (6-4) pyrimidone photoproducts
	Dewar isomers