The predicted protein-sorting transpeptidase that we call exosortase (see TIGR02602) has distinct subclasses that associated with different types of exopolysaccharide production loci. This model represents a distinct clade among a set of amidotransferases largely annotated (not necessarily accurately) as glutatime-hydrolyzing asparagine synthases. Members of this clade are essentially restricted to the characteristic exopolysaccharide (EPS) regions that contain the exosortase 1 genome (xrtA), in genomes that also have numbers of PEP-CTERM domain (TIGR02595) proteins.