Polymorphic nucleotide sites of sigH sequences in L. sakei. The entire CDS sequence (561 nt) was analyzed with MEGA software http://www.megasoftware.net/. Only nucleotide residues different from the upper line sequence are written. The site numbers at the top are in vertical format. Letter-code genetic cluster according to Chaillou et al.  is indicated for each strain and reported subspecies are shaded differently. Polymorphic deduced aa are indicated under the sequence.