FIG. 6.

Potential common processing mechanism of RP4 TrbC (M93696), Bordetella pertussis PtlA (L10720), Brucella suis VirB2 (AF141604), and Brucella abortus VirB2 (AF226278). The latter two sequences are identical and shown once only. Databank GenBank accession numbers are given in parentheses. Only two short portions of the respective sequences are shown. The first and last amino acid positions in each line are numbered according to the original sequences. Lines correspond to conserved residues in all sequences; colons in only two of the sequences. Residues of a proposed common maturation process are printed in white. Arrows mark sites of RP4 TrbC processing.