FIG 2 .

Schematic structure of the zinc metalloproteases. The three black boxes at the left of the structure indicate hydrophobic regions proposed to serve as transmembrane domains in the signal peptide and in combination with the cell wall anchor motif LPXTG. S1 and S2 indicate sites presumably cleaved by the signal peptidase. The G5 domain conserved in the IgA1 proteases and the region used for phylogenetic analyses are indicated. The sequence of the active site is shown for the individual Zmp proteins.