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Literature DB >> 6298746

Characterization of a prokaryotic topoisomerase I activity in chloroplast extracts from spinach.

Abstract

A topoisomerase I activity has been partially purified from crude extracts of spinach chloroplasts. This activity relaxes the supercoiled covalently closed circular DNA of pBR322. The enzyme requires Mg++, but not ATP, and has an apparent molecular weight of about 115,000. It catalyzes a unit change in the linkage number of supercoiled DNA but cannot relax positive supercoiled DNA. These characteristics of the topoisomerase suggest it is of the prokaryotic type and would tend to support the endosymbiotic theory of plastid origin and evolution.

Entities: Chemical Species

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Year: 1983 PMID： 6298746 PMCID： PMC325812 DOI： 10.1093/nar/11.5.1523

Source DB: PubMed Journal: Nucleic Acids Res ISSN： 0305-1048 Impact factor: 16.971

26 in total

1. Evolution of organelles and eukaryotic genomes.

Authors: L Bogorad
Journal: Science Date: 1975-05-30 Impact factor: 47.728

2. A method for determining the sedimentation behavior of enzymes: application to protein mixtures.

Authors: R G MARTIN; B N AMES
Journal: J Biol Chem Date: 1961-05 Impact factor: 5.157

3. Mitochondria contain a distinct DNA topoisomerase.

Authors: F R Fairfield; W R Bauer; M V Simpson
Journal: J Biol Chem Date: 1979-10-10 Impact factor: 5.157

4. An activity from mammalian cells that untwists superhelical DNA--a possible swivel for DNA replication (polyoma-ethidium bromide-mouse-embryo cells-dye binding assay).

Authors: J J Champoux; R Dulbecco
Journal: Proc Natl Acad Sci U S A Date: 1972-01 Impact factor: 11.205

Review 5. Symbiotic theory of the origin of eukaryotic organelles; criteria for proof.

Authors: L Margulis
Journal: Symp Soc Exp Biol Date: 1975

6. Eukaryotic DNA topoisomerases: two forms of type I DNA topoisomerases from HeLa cell nuclei.

Authors: L F Liu; K G Miller
Journal: Proc Natl Acad Sci U S A Date: 1981-06 Impact factor: 11.205

7. Analysis of covalent complexes formed between calf thymus DNA topoisomerase and single-stranded DNA.

Authors: B Prell; H P Vosberg
Journal: Eur J Biochem Date: 1980-07

8. A DNA nicking-closing enzyme encapsidated in vaccinia virus: partial purification and properties.

Authors: W R Bauer; E C Ressner; J Kates; J V Patzke
Journal: Proc Natl Acad Sci U S A Date: 1977-05 Impact factor: 11.205

9. Nucleotide sequence of small ColE1 derivatives: structure of the regions essential for autonomous replication and colicin E1 immunity.

Authors: A Oka; N Nomura; M Morita; H Sugisaki; K Sugimoto; M Takanami
Journal: Mol Gen Genet Date: 1979-05-04

5. An ATP-dependent supercoiling topoisomerase of Chlamydomonas reinhardtii affects accumulation of specific chloroplast transcripts.

Authors: R J Thompson; G Mosig
Journal: Nucleic Acids Res Date: 1985-02-11 Impact factor: 16.971

6. Characterization of DNA topoisomerase activity in two strains of Mycoplasma fermentans and in Mycoplasma pirum.

Authors: S Horowitz; R Maor; E Priel
Journal: J Bacteriol Date: 1997-11 Impact factor: 3.490

7. Characterization of topoisomerase I and II activities in nuclear extracts during callogenesis in immature embryos of Zea mays.

Authors: M Carballo; R Giné; M Santos; P Puigdomènech
Journal: Plant Mol Biol Date: 1991-01 Impact factor: 4.076

Characterization of a prokaryotic topoisomerase I activity in chloroplast extracts from spinach.

1. Evolution of organelles and eukaryotic genomes.

2. A method for determining the sedimentation behavior of enzymes: application to protein mixtures.

3. Mitochondria contain a distinct DNA topoisomerase.

4. An activity from mammalian cells that untwists superhelical DNA--a possible swivel for DNA replication (polyoma-ethidium bromide-mouse-embryo cells-dye binding assay).

Review 5. Symbiotic theory of the origin of eukaryotic organelles; criteria for proof.

6. Eukaryotic DNA topoisomerases: two forms of type I DNA topoisomerases from HeLa cell nuclei.

7. Analysis of covalent complexes formed between calf thymus DNA topoisomerase and single-stranded DNA.

8. A DNA nicking-closing enzyme encapsidated in vaccinia virus: partial purification and properties.

9. Nucleotide sequence of small ColE1 derivatives: structure of the regions essential for autonomous replication and colicin E1 immunity.

10. A gamma-like DNA polymerase in spinach chloroplasts.

1. Purification and properties of DNA topoisomerase I from broccoli.

2. Isolation and characterization of DNA topoisomerase II from cauliflower inflorescences.

3. A DNA topoisomerase type I from wheat embryo mitochondria.

4. Chloroplast DNA gyrase and in vitro regulation of transcription by template topology and novobiocin.

5. An ATP-dependent supercoiling topoisomerase of Chlamydomonas reinhardtii affects accumulation of specific chloroplast transcripts.

6. Characterization of DNA topoisomerase activity in two strains of Mycoplasma fermentans and in Mycoplasma pirum.

7. Characterization of topoisomerase I and II activities in nuclear extracts during callogenesis in immature embryos of Zea mays.

8. A chloroplast DNA helicase II from pea that prefers fork-like replication structures

9. Pea chloroplast topoisomerase I: purification, characterization, and role in replication.

10. Partial purification and characterization of a DNA helicase from chloroplasts of Glycine max.