FIG. 4.
Multiple-sequence alignment of 15 ChpK proteins from gram-negative and gram-positive bacteria. Only ChpK proteins with identified putative antitoxin partners were included in the alignment shown. Amino acids with >80% conservation are shown by the black background. Note the fully conserved proline at position 37 and the fully conserved RP motif at positions +47 and +48. The different species and plasmids from which the ChpK (or PemK) homologues were derived are indicated by the following letters and numbers after the ChpK- (or PemK-) suffix: Dr2, D. radiodurans homologue 2; Mt1, M. tuberculosis homologue 1; Bsu1, B. subtilis homologue 1; Sa, S. aureus; Ef and Ef2, E. faecalis homologues 1 and 2, respectively; Mt2, M. tuberculosis homologue 2; Ef3, E. faecalis homologue 3; Pa, P. acidilactici; Dr1, D. radiodurans homologue 1; Tf, T. ferrooxidans; K12, E. coli K-12; R466B, M. morganii plasmid R446B. Gaps introduced to maximize alignment are indicated by the dashes.