Figure 2. Molecular Phylogeny of the Cas1 Protein across 54 Prokaryotic Genomes.

A representative selection of Cas1 protein sequences were aligned using ClustalW, and columns with greater than 20% gaps were removed. A neighbor-joining tree was calculated in Belvu using the Storm and Sonnhammer distance correction. Trees calculated using more computationally intensive methods showed insignificant differences.

^aFrom the preliminary annotation of the Haloferax volcanii genome, currently sequenced at The Institute for Genomic Research (http://www.tigr.org/tdb/mdb/mdbinprogress.html).