This presumed domain is about 85 residues in length and very rich in charged residues, hence the name RICH (Rich In CHarged residues). It is found in secreted proteins such as PspC Swiss:Q9KK19, SpsA Swiss:O33742 and IgA FC receptor Swiss:P27951 from Streptococcus agalactiae. This domain could be involved in bacterial adherence or cell wall binding.