EC Number   |
Reaction |
Reference |
|---|
   4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
- |
- |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
reaction mechanism, overview |
-, 726998 |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
reaction mechanism, two different routes, overview |
727295 |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
SP repair is initiated by abstraction of a H atom from C6 of SP. The SP(C6) substrate radical is thought to promote a radical-mediated beta-scission of the C-C bond linking the two thymines; the resulting product radical then abstracts an H atom to generate repaired thymine. S-adenosyl-L-methionine as a substrate utilize a defined dinucleotide or dinucleoside SP, rather than SP in intact DNA, suggesting the possibility that stoichiometric SAM cleavage is favored with non-optimal substrates |
-, 748241 |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
SPL is a radical S-adenosylmethionine (SAM) enzyme, reaction mechanism, detailed overview. Radicals are quenched to close the catalytic cycle. The characteristic CXXXCXXC motif is involved in catalysis, although other tri-cysteine motifs may also facilitate this radical chemistry. Enzyme SPL directly directly reverts SP thymine photodimer. The conserved solvent-accessible cysteine 140 is the intrinsic hydrogen atom donor |
-, 748201 |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
SPL is a radical S-adenosylmethionine (SAM) enzyme, reaction mechanism, detailed overview. Radicals are quenched to close the catalytic cycle. The characteristic CXXXCXXC motif is involved in catalysis, although other tri-cysteine motifs may also facilitate this radical chemistry. Enzyme SPL directly reverts SP thymine photodimer. The conserved solvent-accessible cysteine 141 is the intrinsic hydrogen atom donor to the thymine radical |
-, 748201 |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
SPL is a radical S-adenosylmethionine (SAM) enzyme, via a 3'-thymine allylic radical intermediate, reaction mechanism, detailed overview |
-, 748852 |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
spore photoproduct lyase (SPL) repairs 5-thyminyl-5,6-dihydrothymine (i.e., the spore photoproduct (SP)) using a radical transfer pathway that includes at least a cysteine and a tyrosine in germinating endospores. The cysteine (at position 74) and tyrosine are located on the opposite sides of a substrate binding pocket that has to collapse to bring the two residues into proximity, enabling the C->Y radical passage |
-, 748849 |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
the enzyme catalyzes the spore photoproduct repair reaction and combines specific features of radical S-adenosyl-L-methionine and DNA repair enzymes to enable a complex radical-based repair reaction to take place |
-, 728401 |
| 4.1.99.14 | (5R)-5,6-dihydro-5-(thymidin-7-yl)thymidine (in double-helical DNA) = thymidylyl-(3'->5')-thymidylate (in double-helical DNA) |
the enzyme catalyzes the spore photoproduct repair reaction via a radical mediated direct reverse mechanism. At the 1+ oxidation state, the [4Fe-4S] cluster provides an electron to the S-adenosyl-L-methionine, which binds to the cluster in a bidentate manner as the fourth and fifth ligands, to reductively cleave the C-S bond associated with the sulfonium ion in S-adenosyl-L-methionine, generating a reactive 5'-deoxyadenosyl radical. This 5'-dA radical abstracts the proR hydrogen atom from the C6 carbon of spore photoproduct to initiate the repair process. The resulting spore photoproduct radical subsequently fragments to generate a putative thymine methyl radical, which accepts a back-donated H atom to yield the repaired thymidylyl-(3'->5')-thymidylate. Cys141 is involved in the catalytic mechanism as the potential H atom donor to the thymine methyl radical, reaction mechanism, detailed overview. A a thiyl radical is subsequently generated on Cys141 |
-, 727074 |
