Characterization of a reverse gyrase from the extremely thermophilic hydrogen-oxidizing eubacterium Calderobacterium hydrogenophilum

Andera, L

doi:10.1016/0378-1097(93)90250-6

Cited by 7 publications

(9 citation statements)

References 18 publications

(29 reference statements)

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“…Their superhelical densities vary from -0.068 to -0.048; this is in the range of the values previously described for eubacteria (4,45,48 (5,6). Reverse gyrase activity in C hydrogenophilum has been detected by Andera et al (3).…”

Section: Discussionsupporting

confidence: 69%

Comparison of plasmid DNA topology among mesophilic and thermophilic eubacteria and archaebacteria

Charbonnier

Forterre

1994

J Bacteriol

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Several plasmid DNAs have been isolated from mesophilic and thermophilic archaebacteria. Their superhelical densities were estimated at their host strain's optimal growth temperature, and in some representative strains, the presence of reverse gyrase activity (positive DNA supercoiling) Covalently closed DNA molecules so far isolated from eukaryotes and eubacteria are negatively supercoiled to about the same extent. Once purified of proteins, the native DNA molecules exhibit a superhelical density in a range from -0.040 to -0.060 (4,6,48). Negatively supercoiled DNA has a linking deficit, that is, the DNA has fewer duplex turns than would be found in a nicked or linear molecule of the same length. The free energy of negative supercoiling permits all biological processes such as DNA replication, transcription, transposition, and general or site-specific recombination to take place (50). In mesophilic eubacteria, the level of supercoiling is determined essentially by the opposing actions of DNA topoisomerases, which either relax or produce negative superturns in DNA (18). In the eukaryotic nucleus, DNA is negatively supercoiled around the histone core, whereas histone-free DNA is relaxed by either DNA topoisomerase I or II (50).In thermophilic organisms, the situation is not so clear. The major DNA topoisomerase activity detected in extremely thermophilic and hyperthermophilic archaebacteria is due to reverse gyrase (6,29,30). This ATP-dependent DNA topoisomerase I is able to introduce positive superturns into DNA (23,38,40). Such DNA has an excess of links, which could help to stabilize it at high temperatures. Reverse gyrase has also been found in species of the order Thermotogales (5) We have recently found that the DNA of the plasmid pGT5, isolated from the newly identified hyperthermophilic sulfurmetabolizing archaebacterium GE5, is relaxed at 95'C, the optimal growth temperature of its host strain (9). This relaxed state is completely different from that of the negatively supercoiled DNA of extrachromosomal elements that have been previously studied in mesophilic eubacteria and eukaryotes.In order to determine whether this unusual topological situation is universal to the thermophilic organisms, we purified several plasmid DNAs from mesophilic and thermophilic eubacteria as well as archaebacteria and determined their superhelical densities at the physiological growth temperature of the host strains.The results reported here strongly suggest the existence of two groups of plasmids. The group I plasmids have a highly negatively supercoiled DNA and were all isolated from eubacteria and mesophilic archaebacteria. In contrast, group II plasmids exhibit a relaxed DNA and belong exclusively to thermophilic archaebacterial group. An additional result is that all thermophilic archaebacteria that possess a relaxed plasmid DNA show strong reverse gyrase-like activity, with the exception of a moderately thermophilic archaebacterium that possesses a relaxed plasmidic DNA but has no detectable reverse gyrase activity. ...

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Section: Discussionsupporting

confidence: 69%

Comparison of plasmid DNA topology among mesophilic and thermophilic eubacteria and archaebacteria

Charbonnier

Forterre

1994

J Bacteriol

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“…[17][18][19] The temperature optimum of T. maritima reverse gyrase is at 75°C, which was therefore used as the standard temperature for all supercoiling reactions.…”

Section: Relaxation Of Negatively Supercoiled Plasmid and Positive Sumentioning

confidence: 99%

Adenosine 5′-O-(3-thio)triphosphate (ATPγS) Promotes Positive Supercoiling of DNA by T. maritima Reverse Gyrase

Jungblut

Klostermeier

2007

Journal of Molecular Biology

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“…We have previously discovered the existence of a reverse gyrase in an order of extremely thermophilic bacteria, Thermotogales (5). Since then, another reverse gyrase, isolated from the thermophilic bacterium Calderobacterium hydrogenophilum, has been purified and biochemically characterized as a monomer of about 120 kDa (2). However, no bacterial reverse gyrase gene sequence has so far been obtained.…”

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Reverse gyrase from hyperthermophiles: probable transfer of a thermoadaptation trait from Archaea to Bacteria

et al. 2000

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The hyperthermophilic bacterium Thermotoga maritima MSB8 possesses a reverse gyrase whose enzymatic properties are very similar to those of archaeal reverse gyrases. It catalyzes the positive supercoiling of the DNA in an Mg 2؉ -and ATP-dependent process. Its optimal temperature of activity is around 90°C, and it is highly thermostable. We have cloned and DNA sequenced the corresponding gene (T. maritima topR). This is the first report describing the analysis of a gene encoding a reverse gyrase in bacteria. The T. maritima topR gene codes for a protein of 1,104 amino acids with a deduced molecular weight of 128,259, a value in agreement with that estimated from the denaturing gel electrophoresis of the purified enzyme. Like its archaeal homologs, the T. maritima reverse gyrase exhibits helicase and topoisomerase domains, and its sequence matches very well the consensus sequence for six reverse gyrases now available. Phylogenetic analysis shows that all reverse gyrases, including the T. maritima enzyme, form a very homogeneous group, distinct from the type I 5 topoisomerases of the TopA subfamily, for which we have previously isolated a representative gene in T. What are the molecular mechanisms involved in the adaptation of life to elevated temperatures? In terms of DNA dynamics, part of the answer was provided by the discovery in thermophilic organisms of a particular topoisomerase, the reverse gyrase, that modifies the topological state of DNA by introducing positive supercoils in an ATP-dependent process (14). It was suggested that overlinking could compensate for the effect of temperature on DNA structure (16). The enzyme is widely distributed in thermophilic archaea (6,8). The first reverse gyrase characterized was isolated from the hyperthermophilic archaeum Sulfolobus acidocaldarius (23,33). Mechanistic studies showed that it is transiently linked to the DNA by a 5Ј phosphotyrosyl bond (22,24), classifying it in the type I 5Ј topoisomerase family as proposed by Roca (38). Sequence analysis further showed that it is a single polypeptide containing putative helicase and topoisomerase domains located in the amino-and carboxy-terminal, respectively, parts of the protein (9). The helicase domain exhibits motifs found in DNA and RNA helicases, and the topoisomerase domain exhibits a significant similarity with the 5Ј topoisomerase I (protein ) from Escherichia coli. From all of these data, a mechanism of reverse gyration involving the concerted action of two such domains was proposed (9, 14).To date, four other archaeal reverse gyrase genes have been sequenced: from Sulfolobus shibatae (21), Methanopyrus kandleri (26), Pyrococcus furiosus (3), and Methanococcus jannaschii (7). A comparative analysis of reverse gyrases from two members of the order Sulfolobales (S. acidocaldarius and S. shibatae) and M. kandleri with the other type I topoisomerases of the 5Ј family (21) showed that the reverse gyrases constitute a new group within this family distinct from the previously described TopA and TopB groups, represent...

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Characterization of a reverse gyrase from the extremely thermophilic hydrogen-oxidizing eubacterium Calderobacterium hydrogenophilum

Cited by 7 publications

References 18 publications

Comparison of plasmid DNA topology among mesophilic and thermophilic eubacteria and archaebacteria

Comparison of plasmid DNA topology among mesophilic and thermophilic eubacteria and archaebacteria

Adenosine 5′-O-(3-thio)triphosphate (ATPγS) Promotes Positive Supercoiling of DNA by T. maritima Reverse Gyrase

Reverse gyrase from hyperthermophiles: probable transfer of a thermoadaptation trait from Archaea to Bacteria

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