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topIb, a phylogenetic hallmark gene of Thaumarchaeota encodes a functional eukaryote-like topoisomerase IB
- Source :
- Nucleic Acids Research, Nucleic Acids Research, Oxford University Press, 2016, 44 (6), pp.2795-2805. ⟨10.1093/nar/gkw097⟩, Nucleic Acids Research, Oxford University Press, 2016, 44 (6), pp.2795-2805. 〈10.1093/nar/gkw097〉, Nucleic Acids Research, 2016, 44 (6), pp.2795-2805. ⟨10.1093/nar/gkw097⟩
- Publication Year :
- 2016
- Publisher :
- HAL CCSD, 2016.
-
Abstract
- International audience; Type IB DNA topoisomerases can eliminate torsional stresses produced during replication and transcription. These enzymes are found in all eukaryotes and a short version is present in some bacteria and viruses. Among prokaryotes, the long eukaryotic version is only observed in archaea of the phylum Thau-marchaeota. However, the activities and the roles of these topoisomerases have remained an open question. Here, we demonstrate that all available thaumar-chaeal genomes contain a topoisomerase IB gene that defines a monophyletic group closely related to the eukaryotic enzymes. We show that the topIB gene is expressed in the model thaumarchaeon Ni-trososphaera viennensis and we purified the recom-binant enzyme from the uncultivated thaumarchaeon Candidatus Caldiarchaeum subterraneum. This enzyme is active in vitro at high temperature, making it the first thermophilic topoisomerase IB characterized so far. We have compared this archaeal type IB enzyme to its human mitochondrial and nuclear counterparts. The archaeal enzyme relaxes both negatively and positively supercoiled DNA like the eukaryotic enzymes. However, its pattern of DNA cleavage specificity is different and it is resistant to camptothecins (CPTs) and non-CPT Top1 inhibitors, LMP744 and lamellarin D. This newly described ther-mostable topoisomerases IB should be a promising new model for evolutionary, mechanistic and structural studies.
- Subjects :
- 0301 basic medicine
Models, Molecular
Thaumarchaeota
Hot Temperature
Archaeal Proteins
Molecular Sequence Data
Gene Expression
Topoisomerase-I Inhibitor
Genome
Heterocyclic Compounds, 4 or More Rings
Protein Structure, Secondary
Mitochondrial Proteins
03 medical and health sciences
chemistry.chemical_compound
Coumarins
Genetics
Escherichia coli
Humans
[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology
Amino Acid Sequence
Cloning, Molecular
Gene
[ SDV.BBM ] Life Sciences [q-bio]/Biochemistry, Molecular Biology
Phylogeny
biology
DNA, Superhelical
Protein Stability
Nucleic Acid Enzymes
Topoisomerase
biology.organism_classification
Isoquinolines
Archaea
Recombinant Proteins
Protein Structure, Tertiary
030104 developmental biology
chemistry
DNA Topoisomerases, Type I
biology.protein
DNA supercoil
Eukaryote
Camptothecin
Topoisomerase I Inhibitors
Sequence Alignment
DNA
Subjects
Details
- Language :
- English
- ISSN :
- 03051048 and 13624962
- Database :
- OpenAIRE
- Journal :
- Nucleic Acids Research, Nucleic Acids Research, Oxford University Press, 2016, 44 (6), pp.2795-2805. ⟨10.1093/nar/gkw097⟩, Nucleic Acids Research, Oxford University Press, 2016, 44 (6), pp.2795-2805. 〈10.1093/nar/gkw097〉, Nucleic Acids Research, 2016, 44 (6), pp.2795-2805. ⟨10.1093/nar/gkw097⟩
- Accession number :
- edsair.doi.dedup.....84b599c636ab793f6d64cbbd762cc1a6