Facilitation of CRISPR adaptation

  • Abedon S
  • 46


    Mendeley users who have this article in their library.
  • N/A


    Citations of this article.


CRISPR systems, as bacterial defenses against phages, logically must display in their functioning a sequence of at least three major steps. These, in order of occurrence, are "facilitation," adaptation and interference, where the facilitation step is the main issue considered in this commentary. Interference is the blocking of phage infections as mediated in part by CRISPR spacer sequences. Adaptation, at least as narrowly defined, is the acquisition of these spacer sequences by CRISPR loci. Facilitation, in turn and as defined here, corresponds to phage-naive bacteria avoiding death follow first-time exposure to specific phages, where bacterial survival of course is necessary for subsequent spacer acquisition. Working from a variety of perspectives, I argue that a requirement for facilitation suggests that CRISPR systems may play secondary rather than primary roles as bacterial defenses, particularly against more virulent phages. So considered, the role of facilitation in CRISPR functioning could be viewed as analogous to the building, in vertebrate animals, of adaptive immunity upon an immunological foundation comprised of mechanisms that are both more generally acting and innate.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Stephen T. Abedon

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free