Figure 1.

Purification and RNA Content of the CSM Complex from S. solfataricus

(A) Gene organization of the csm locus in selected crenarchaeal species. The gene order is conserved and typically includes a gene encoding Cas6 for crRNA processing. Gene numbers are shown and are contiguous on the genome. Abbreviations are as follows: Sso, S. solfataricus; Sto, S. tokodaii; Sac, S. acidocaldarius; Sis, S. islandicus strain M.14.25; Msed, Metallosphaera sedula; Tpen, Thermofilum pendens. T. pendens Cas6 is present elsewhere on the genome.

(B) Fractions of the CSM complex eluting from the final gel-filtration column during purification. All eight subunits can be visualized and detected by MS.

(C) RNA purified from the purified CSM complex. A single discrete band around 50 nt was observed.

(D) A linear coverage map for a series of eight spacers from the S. solfataricus P1 A locus is shown. 5′ ends were defined by the 8 nt 5′-handle derived from cleavage of the repeat by Cas6.

(E) Linear coverage map for the entire CRISPR C locus from S. solfataricus P1, highlighting the variability in coverage.