Comparison of the sequences of native peroxisomal proteins, along with mutational analysis coupled with targeting studies and assessment of PEX5 binding preferences, established that the PTS1 is in fact a family of sequences which generally conform to the pattern of [small side chain amino acid]–[basic amino acid]–[hydrophobic amino acid], but in some cases can be considerably more diverse and hinted that residues immediately adjacent to the C-terminal tripeptide might have an auxiliary function