The nucleotide sequences of Smr15C1 and Smr15C2 were initially used as query to search against the Rfam database (version 10.0; http://www.sanger.ac.uk/Software/Rfam).
Both S.melilloti αr15 sRNAs were also BLASTed with default parameters against all the currently available bacterial genomes (1,615 sequences at 20 April 2011; http://www.ncbi.nlm.nih.gov).