Intrinsic sequence specificity of the Cas1 integrase directs new spacer acquisition

  1. Clare Rollie
  2. Stefanie Schneider
  3. Anna Sophie Brinkmann
  4. Edward L Bolt
  5. Malcolm F White  Is a corresponding author
  1. University of St Andrews, United Kingdom
  2. University of Duisburg-Essen, Germany
  3. University of Nottingham, United Kingdom

Abstract

The adaptive prokaryotic immune system CRISPR-Cas provides RNA-mediated protection from invading genetic elements. The fundamental basis of the system is the ability to capture small pieces of foreign DNA for incorporation into the genome at the CRISPR locus, a process known as Adaptation, which is dependent on the Cas1 and Cas2 proteins. We demonstrate that Cas1 catalyses an efficient trans-esterification reaction on branched DNA substrates, which represents the reverse- or disintegration reaction. Cas1 from both Escherichia coli and Sulfolobus solfataricus display sequence specific activity, with a clear preference for the nucleotides flanking the integration site at the leader-repeat 1 boundary of the CRISPR locus. Cas2 is not required for this activity and does not influence the specificity. This suggests that the inherent sequence specificity of Cas1 is a major determinant of the adaptation process.

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Author details

  1. Clare Rollie

    Biomedical Sciences Research Complex, University of St Andrews, St Andrews, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Stefanie Schneider

    Faculty of Medicine, Institute of Cell Biology, University of Duisburg-Essen, Essen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Anna Sophie Brinkmann

    School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Edward L Bolt

    School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Malcolm F White

    Biomedical Sciences Research Complex, University of St Andrews, St Andrews, United Kingdom
    For correspondence
    mfw2@st-and.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Rollie 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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  1. Clare Rollie
  2. Stefanie Schneider
  3. Anna Sophie Brinkmann
  4. Edward L Bolt
  5. Malcolm F White
(2015)
Intrinsic sequence specificity of the Cas1 integrase directs new spacer acquisition
eLife 4:e08716.
https://doi.org/10.7554/eLife.08716

Share this article

https://doi.org/10.7554/eLife.08716

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