Apolipoprotein L-I (apoL1) is a human-specific serum protein that kills Trypanosoma brucei through ionic pore formation in endosomal membranes of the parasite. The T. brucei subspecies rhodesiense and gambiense resist this lytic activity and can infect humans, causing sleeping sickness.
View Article and Find Full Text PDFApolipoprotein L-I is the trypanolytic factor of human serum. Here we show that this protein contains a membrane pore-forming domain functionally similar to that of bacterial colicins, flanked by a membrane-addressing domain. In lipid bilayer membranes, apolipoprotein L-I formed anion channels.
View Article and Find Full Text PDFThe heterodimeric transferrin receptors of Trypanosoma brucei (Tf-Rs) are encoded by two genes termed ESAG7 and ESAG6. These genes belong to polycistronic transcription units contained in the multiple expression sites for the variant surface glycoprotein (VSG ESs), only one of which is active at a time. Each VSG ES carries a different copy of these genes, leading to alternative expression of Tf-Rs with quite distinct binding affinities for transferrins from various mammals.
View Article and Find Full Text PDFHuman sleeping sickness in east Africa is caused by the parasite Trypanosoma brucei rhodesiense. The basis of this pathology is the resistance of these parasites to lysis by normal human serum (NHS). Resistance to NHS is conferred by a gene that encodes a truncated form of the variant surface glycoprotein termed serum resistance associated protein (SRA).
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