CELL-SURFACE COMPONENTS OF LEISHMANIA - IDENTIFICATION OF A NOVEL PARASITE LECTIN

Protozoan parasites of the genus Leishmania have a glycoconjugate surf ace coat (the glycocalyx) that acts as the interface between the paras ite and its external environment, The prinicipal components of the gly cocalyx, the lipophosphoglycans and the glycoinositolphospholipids, ha ve a variety of functions that facilitate parasite survival in both th e extracellular and the intracellular stages of the life cycle. Recent ly, a novel hydrophilic Leishmania protein, the Gene B protein, has be en identified on the surface of infective parasite stages. Attachment to the surface appears to be by association between a region of repeat ed amino acids in this molecule and components of the glycocalyx, As a consequence, the Gene B protein is exposed on the parasite surface wh ile other peptides are buried beneath the glycocalyx, The putative fun ctions of this unusual molecule are discussed.