A reversible protein phosphorylation system is present at the surface of infective larvae of the parasitic nematode Trichinella spiralis.
Trichinella spiralis infective larvae have externally oriented enzymes catalysing reversible protein phosphorylation on their surface. Incubation of larvae with exogenous ATP resulted in phosphorylation of surface bound and released proteins. Exposure of the parasites to bile, a treatment which renders them infective for intestinal epithelia, resulted in increased release of protein and an altered profile of phosphorylation. Both serine/threonine and tyrosine phosphorylation and dephosphorylation reactions took place at the parasite surface. Examination of the structural characteristics of the larvae following exposure to bile showed that the non-bilayer surface coat was not shed but was structurally reorganised.
Smith
V P
VP
Department of Biochemistry, Imperial College of Science, Technology and Medicine, London SW7 2AY, UK.
Selkirk
M E
ME
Gounaris
K
K
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015801:Helminth Proteins / Q000378:metabolism; D007814:Larva / Q000201:enzymology* / Q000378:metabolism / Q000648:ultrastructure; D008854:Microscopy, Electron; D010750:Phosphoproteins / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010761:Phosphorus Radioisotopes; D010766:Phosphorylation / Q000187:drug effects; D047428:Protein Kinase Inhibitors; D011494:Protein Kinases / Q000378:metabolism*; D017160:Trichinella spiralis / Q000201:enzymology* / Q000378:metabolism / Q000648:ultrastructure
D004791:Enzyme Inhibitors; D015801:Helminth Proteins; D010750:Phosphoproteins; D010761:Phosphorus Radioisotopes; D047428:Protein Kinase Inhibitors; D000255:Adenosine Triphosphate; D011494:Protein Kinases; D010744:Phosphoric Monoester Hydrolases