SCHISTOSOMA-MANSONI - THE GLUCOSE-TRANSPORT PROTEIN SGTP4 IS PRESENT IN TEGUMENTAL MULTILAMELLAR BODIES, DISCOID BODIES, AND THE SURFACE LIPID BILAYERS

Schistosomes metabolize large quantities of glucose obtained from the host serum by facilitated diffusion through the tegument. Here we have used rabbit antibodies affinity purified against the carboxyl terminu s of a facilitated glucose transporter, SGTP4, to localize the antigen in both schistosomula and adult. By ultrastructural immunocytochemica l analysis, SGTP4 was localized to both lipid bilayers that cover the tegumental surface of adults and schistosomula. In the inner bilayer o f adults, SGTP4 was apparently oriented with the carboxyl terminus on the internal side of the bilayer. SGTP4 was also present in the discoi d and multilamellar bodies in adults and the membranous bodies in schi stosomula. Finally, the affinity purified antibodies against SGTP4 bou nd nonspecifically to the head gland, and postacetabular glands in sch istosomula. The localization of the antigen in the two surface Lipid b ilayers suggests that SGTP4 may be responsible for transporting glucos e from mammalian host serum into the tegument. (C) 1996 Academic Press , Inc.