Fig. 5

Sizes of CRISPR array repeats and spacers. a Distribution of sizes of the representative repeats for each array, the percentage of each length is shown separately for bacteria (blue) and archaea (yellow). Four size ranges- small, medium, large, and extra large are indicated. b Distribution of the median spacer size for each array. In (a) and (b) CRISPR arrays with ‘good’ scores (≥4.0) and three or more repeats from one strain for each species from Genbank/genomes were counted. For the same analysis including all strains, see Additional file 1: Figure S3