FIG. 4.

Nucleotide and amino acid sequences of the mutD/dnaQ gene and the ɛ protein. For the mutD nucleotide sequence, numbering is given at the right relative to the ATG translation start site (+1); the amino acid sequence of ɛ, given below in single-letter code, is also numbered at the right. Putative Exo I, Exo II (3), and two Exo III motifs (3, 4) are underlined; Exo IIIɛ (1) is underlined with a dotted line (the C-terminal homology of the ɛ subunit with gram-positive bacteria ends somewhere between E192 and V206 in the alignment of Barnes et al. [1]), and crucial amino acids in all putative Exo motifs are doubly underlined.