1. Biochemistry and Chemical Biology
  2. Chromosomes and Gene Expression
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SMC condensin entraps chromosomal DNA by an ATP hydrolysis dependent loading mechanism in Bacillus subtilis

  1. Larissa Wilhelm
  2. Frank Bürmann
  3. Anita Minnen
  4. Ho-Chul Shin
  5. Christopher P Toseland
  6. Byung-Ha Oh
  7. Stephan Gruber  Is a corresponding author
  1. Max Planck Institute of Biochemistry, Germany
  2. Korea Research Institute of Bioscience and Biotechnology, Republic of Korea
  3. Korea Advanced Institute of Science and Technology, Republic of Korea
Research Article
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Cite this article as: eLife 2015;4:e06659 doi: 10.7554/eLife.06659

Abstract

Smc-ScpAB forms elongated, annular structures that promote chromosome segregation, presumably by compacting and resolving sister DNA molecules. The mechanistic basis for its action, however, is only poorly understood. Here, we have established a physical assay to determine whether the binding of condensin to native chromosomes in Bacillus subtilis involves entrapment of DNA by the Smc-ScpAB ring. To do so, we have chemically cross-linked the three ring interfaces in Smc-ScpAB and thereafter isolated intact chromosomes under protein denaturing conditions. Exclusively species of Smc-ScpA, which were previously cross-linked into covalent rings, remained associated with chromosomal DNA. DNA entrapment is abolished by mutations that interfere with the Smc ATPase cycle and strongly reduced when the recruitment factor ParB is deleted, implying that most Smc-ScpAB is loaded onto the chromosome at parS sites near the replication origin. We furthermore report a physical interaction between native Smc-ScpAB and chromosomal DNA fragments.

Article and author information

Author details

  1. Larissa Wilhelm

    Chromosome Organization and Dynamics, Max Planck Institute of Biochemistry, Martinsried, Germany
    Competing interests
    The authors declare that no competing interests exist.

  2. Frank Bürmann

    Chromosome Organization and Dynamics, Max Planck Institute of Biochemistry, Martinsried, Germany
    Competing interests
    The authors declare that no competing interests exist.

  3. Anita Minnen

    Chromosome Organization and Dynamics, Max Planck Institute of Biochemistry, Martinsried, Germany
    Competing interests
    The authors declare that no competing interests exist.

  4. Ho-Chul Shin

    Functional Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
    Competing interests
    The authors declare that no competing interests exist.

  5. Christopher P Toseland

    Chromosome Organization and Dynamics, Max Planck Institute of Biochemistry, Martinsried, Germany
    Competing interests
    The authors declare that no competing interests exist.

  6. Byung-Ha Oh

    Department of Biological Sciences, KAIST Institute for the Biocentury, Cancer Metastasis Control Center, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
    Competing interests
    The authors declare that no competing interests exist.

  7. Stephan Gruber

    Chromosome Organization and Dynamics, Max Planck Institute of Biochemistry, Martinsried, Germany
    For correspondence
    sgruber@biochem.mpg.de
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Bernard de Massy, Institute of Human Genetics, CNRS UPR 1142, France

Publication history

  1. Received: January 25, 2015
  2. Accepted: May 6, 2015
  3. Accepted Manuscript published: May 7, 2015 (version 1)
  4. Accepted Manuscript updated: May 8, 2015 (version 2)
  5. Version of Record published: May 26, 2015 (version 3)

Copyright

© 2015, Wilhelm et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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