The rise and fall of CRISPRs - dynamics of spacer acquisition and loss

E.R. Westra, S.J.J. Brouns

Research output: Contribution to journalArticleAcademicpeer-review

19 Citations (Scopus)

Abstract

Bacteria and Archaea are continuously exposed to mobile genetic elements (MGE), such as viruses and plasmids. MGEs may provide a selective advantage, may be neutral or may cause cell damage. To protect against invading DNA, prokaryotes utilize a number of defence systems, including the CRISPR/Cas system. CRISPR/Cas systems rely on integration of invader sequences (spacers) into CRISPR loci that act as a genetic memory of past invasions. Processed CRISPR transcripts are utilized as guides by Cas proteins to cleave complementary invader nucleic acids. In this issue, two groups report on spacer acquisition and turnover dynamics of CRISPR loci in a thermoacidophilic archeon and a pathogenic bacterium. Erdmann and Garrett demonstrate that three of the six CRISPR loci of Sulfolobus solfataricus rapidly acquire new spacer sequences from a conjugative plasmid present in a virus mixture. Intriguingly, two distinct mechanisms of spacer integration are utilized: leader adjacent and internal CRISPR spacer acquisition. Lopez-Sanchez and co-workers studied the type II system of Streptococcus agalactiae and observe heterogeneity in the bacterial population. A fraction of the population lost one or more anti-mobilome spacer sequences during its cultivation, allowing the transfer of a MGE in this subpopulation and a rapid response to altering selection pressures
Original languageEnglish
Pages (from-to)1021-1025
JournalMolecular Microbiology
Volume85
Issue number6
DOIs
Publication statusPublished - 2012

Keywords

  • immune-system
  • streptococcus-thermophilus
  • acquired-resistance
  • antiviral defense
  • escherichia-coli
  • seed sequence
  • cas systems
  • rna
  • dna
  • repeats

Fingerprint Dive into the research topics of 'The rise and fall of CRISPRs - dynamics of spacer acquisition and loss'. Together they form a unique fingerprint.

Cite this