4.1.99.3	cyclobutadipyrimidine (in DNA)	-	
4.1.99.3	cyclobutadipyrimidine (in DNA)	the enzyme is involved in biological photoreactivation	
4.1.99.3	cyclobutadipyrimidine (in DNA)	photolyases utilize near-ultraviolet blue light to specifically repair the major photoproducts of UV-induced damaged DNA. The enzyme specifically repairs CPD lesions	
4.1.99.3	cyclobutadipyrimidine (in DNA)	the enzyme catalyses light-driven DNA repair and photoreduction, but in contrast to class I enzymes lacks a high degree of binding discrimination between UV-damaged and intact duplex DNA	
4.1.99.3	cyclobutadipyrimidine in DNA	DNA repair enzyme can absorb blue/ultraviolet A light as energy and split a pyrimidine dimer induced by ultraviolet radiation. PHR1 gene encodes a functional photolyase. The PHR1 transcripts are specifically enhanced by near-ultraviolet radiation (300-400 nm) and by sunlight	
4.1.99.3	cyclobutadipyrimidine in DNA	the enzyme is one of the main factors determining UVB sensitivity in Oryza sativa. Cultivar Sasanishiki is resistant to the damaging effects of UVB while cultivar Norin 1 is less resistant. Amino acid position 126 is Arg in cultivar Norin 1 and Gln in cultivar Sasanishiki. The single amino acid alteration from Gln to Arg leads to a deficit of CPD photolyase activity	
4.1.99.3	cyclobutadipyrimidine in DNA	-	
4.1.99.3	cyclobutadipyrimidine in DNA	DNA repair activity	
4.1.99.3	cyclobutadipyrimidine in DNA	the enzyme binds to DNA containing pyrimidine dimers with high affinity and then breaks the cyclobutane ring joining the two pyrimidines of the dimer in a light-dependent reaction, 300-500 nm	
4.1.99.3	cyclobutadipyrimidine in DNA	light-dependent(300-600 nm) monomerization of cyclobutyl pyrimidine dimers, formed between adjacent pyrimidines on the same DNA strand, upon exposure to UV irradiation, 220-320 nm