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DNA Topoisomerases, Type I MeSH Descriptor Data 2026


MeSH Heading
DNA Topoisomerases, Type I
Tree Number(s)
D08.811.399.403.483
D12.776.157.687.375
D12.776.660.720.375
Unique ID
D004264
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D004264
Annotation
do not confuse entry term DNA UNTWISTING PROTEIN with DNA UNWINDING PROTEINS see DNA HELICASES; coordinate with BACTERIAL PROTEINS or ARCHAEAL PROTEINS if pertinent
Scope Note
DNA TOPOISOMERASES that catalyze ATP-independent breakage of one of the two strands of DNA, passage of the unbroken strand through the break, and rejoining of the broken strand. DNA Topoisomerases, Type I enzymes reduce the topological stress in the DNA structure by relaxing the superhelical turns and knotted rings in the DNA helix.
Entry Term(s)
DNA Nicking-Closing Protein
DNA Nicking-Closing Proteins
DNA Relaxing Enzyme
DNA Relaxing Enzymes
DNA Relaxing Protein
DNA Topoisomerase
DNA Topoisomerase I
DNA Topoisomerase III
DNA Topoisomerase III alpha
DNA Topoisomerase III beta
DNA Type 1 Topoisomerase
DNA Untwisting Enzyme
DNA Untwisting Enzymes
DNA Untwisting Protein
DNA Untwisting Proteins
TOP3 Topoisomerase
TOP3alpha
TOPO IIIalpha
Topo III
Topoisomerase I
Topoisomerase III
Topoisomerase III beta
Topoisomerase IIIalpha
Topoisomerase IIIbeta
Type I DNA Topoisomerase
Registry Numbers
EC 5.99.1.2
0
Related Numbers
143180-75-0
CAS Type 1 Name
DNA topoisomerase
Previous Indexing
Deoxyribonucleases (1966-1977)
DNA, Circular (1973-1977)
Polynucleotide Synthetases (1973-1977)
Proteins (1966-1977)
specific protein (1966-1977)
Public MeSH Note
2002; see DNA TOPOISOMERASE 1994-2001, see DNA UNTWISTING PROTEINS 1978-1993; for DNA NICKING-CLOSING PROTEIN see DNA NICKING-CLOSING PROTEINS 1978-1993; for DNA RELAXING ENZYME see DNA RELAXING ENZYMES 1978-1993; for DNA UNTWISTING ENZYME see DNA UNTWISTING ENZYMES 1978-1993
History Note
2002
Entry Combination
antagonists & inhibitors:Topoisomerase I Inhibitors
Date Introduced
1978/01/01
Last Updated
2019/07/08
DNA Topoisomerases, Type I Preferred
DNA Topoisomerase III alpha Narrower
DNA Topoisomerase III beta Narrower
DNA Topoisomerase III Narrower
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