Variation in the nature of attachment of phosphorylcholine to excretory-secretory products of adult Brugia pahangi.
The mechanism of linkage of phosphorylcholine (PC) to excretory-secretory products (ES) of adult Brugia pahangi has been investigated. Biosynthetic radio-isotope labelling of ES with [3H]choline followed by SDS-PAGE/fluorography revealed a smear of molecular weight approximately 40-100 kDa which loses its radiolabel following exposure to N-glycosidase F, but not mild alkali. PC is thus attached to this smear of molecules via N-type glycans, a mechanism of linkage previously observed with respect to PC-ES of Acanthocheilonema viteae. Western blotting analysis of non-radiolabelled ES demonstrated the existence of additional PC-ES which were insensitive to N-glycosidase F, but not to alkali. This second group of molecules is therefore likely to contain PC linked to O-glycans. Filarial nematodes may thus utilize 2 classes of glycan for attachment of PC. Examination of B. pahangi and A. viteae whole worm extracts by Western blotting indicated that their PC content could not be cleaved by N-glycosidase F and hence the use of N-type glycans may be restricted to a subset of ES products. The implications of these findings with respect to developing inhibitors of PC attachment for use as anti-filarial drugs are discussed.
Nor
Z M
ZM
Department of Immunology, University of Strathclyde, Glasgow.
Houston
K M
KM
Devaney
E
E
Harnett
W
W
D000581:Amidohydrolases / Q000378:metabolism; D000818:Animals; D000947:Antigens, Helminth / Q000737:chemistry / Q000378:metabolism*; D015153:Blotting, Western; D017179:Brugia pahangi / Q000737:chemistry* / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D015801:Helminth Proteins / Q000737:chemistry / Q000378:metabolism*; D008970:Molecular Weight; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase; D010767:Phosphorylcholine / Q000737:chemistry / Q000378:metabolism*; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*
D000947:Antigens, Helminth; D015801:Helminth Proteins; D011134:Polysaccharides; D010767:Phosphorylcholine; D000581:Amidohydrolases; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase