Alignment of PorM1 and PorM2 from M. fortuitum and MspA and MspC from M. smegmatis. The start codon ATG and the stop codon TGA were chosen according to the sequence of mspA. The cleavage recognition site of the signal peptidase was predicted for PorM1, PorM2 and MspC using the SignalP 3.0 Server at http://www.cbs.dtu.dk/services/SignalP/. The predicted signal peptide cleavage sites corresponded to the signal peptide cleavage site of MspA . Identical amino acids are dark grey, similar amino acids are light grey and different amino acids are not shaded. For PorM1 and MspA an identity index of 94.8% was calculated, while PorM2 showed an amino acid identity of 90.7% to MspA.