Phage Response to CRISPR-Encoded Resistance in Streptococcus thermophilus

• DOI: 10.1128/jb.01412-07
• Publication Date: 2007-12-08T01:53:35Z
• Authors: Hélène Deveau; Rodolphe Barrangou; Josiane E. Garneau; Jessica Labonté; Christophe Fremaux; Patrick Boyaval; Dennis A. Romero; Philippe Horvath; Sylvain Moineau
• Keywords: Phagemid

ABSTRACT Clustered regularly interspaced short palindromic repeats (CRISPR) and their associated genes are linked to a mechanism of acquired resistance against bacteriophages. Bacteria can integrate stretches phage-derived sequences (spacers) within CRISPR loci become phage resistant. In this study, we further characterized the efficiency CRISPR1 as in Streptococcus thermophilus . First, show that is distinct from previously known defense systems effective two main groups S. phages. Analyses 30 bacteriophage-insensitive mutants indicate addition one new spacer most frequent outcome challenge iterative spacers increases overall host. The added have size between 29 31 nucleotides, with being by far frequent. Comparative analysis 39 newly complete genomic wild-type phages 2972, 858, DT1 demonstrated must be identical region (named proto-spacer) genome confer phenotype. Moreover, found CRISPR1-specific sequence (NNAGAAW) located downstream proto-spacer important for Finally, through analyses 20 mutant virulent rapidly evolving single nucleotide mutations well deletions, response CRISPR1.