This family represents the C-terminus of bacterial Erp proteins that seem to be specific to Borrelia burgdorferi (a causative agent of Lyme disease). Borrelia Erp proteins are particularly heterogeneous, which might enable them to interact with a wide variety of host components [1].

1: Immune evasion of Borrelia burgdorferi: mapping of a complement-inhibitor factor H-binding site of BbCRASP-3, a novel member of the Erp protein family. Kraiczy P, Hellwage J, Skerka C, Kirschfink M, Brade V, Zipfel PF, Wallich R; Eur J Immunol 2003;33:697-707. PMID:12616490