Diversity of the CRISPR1 locus in 13 Streptococcus agalactiae strains. Spacers were identified by the CRISPRtionary program, attributing a number to each spacer . Repeats are not shown and spacers are represented in arbitrarily colored boxes. Strains with similar spacer arrays are arranged together and their names are given on the left. Single spacers appear in white boxes framed in black; identical spacers shared by different strains are shown with a same color background with black numbers; homologous spacers in the same strain are represented using the same color background and white numbers. The special spacers are underlined in red.