Mass spectrometric analyses of CL(39), CL(41) and H(1), H(2), H(3) confirm identity with fetidin and lysenin produced by earthworm leukocytes.

Antibacterial proteins realize effective immunological mechanisms against invading pathogens. Some of them exert hemolytic and agglutinating properties. Here, we analyzed two hemolysins isolated from cell lysate (CL(39) and CL(41)) and three hemolytic proteins isolated from coelomic fluid (H(1), H(2) and H(3)) of the annelid Eisenia fetida using mass spectrometry and bioinformatics. We demonstrated the identity of CL(39,41) with fetidin and lysenin; these have been described earlier. H(1-3) share sequence components with fetidin but they seem to be glycosylated as shown for H(1). The results help to resolve a long debate concerning nomenclature and identity of these hemolytic proteins. They support: (1). the concept that the hemolytic proteins originate from chloragocytes; (2). their origin to some extent from large coelomocytes; and (3). the view that they are secreted into CF.