Cell free systems trypanosomes

Analysis of GPI anchor biosynthesis was greatly facilitated by the development of a cell free system in trypanosomes [62]. The convenience of this system can not be overstated. It is a highly stable system which can be stored frozen for long periods... 

The lack of SL RNA cap recognition in nematode trans-splicing stands in apparent contrast to recent results obtained in trypanosomes. Two groups have shown that trypanosome SL RNAs, undermethylated in the cap structure, do no function in trans-splicing. These results suggest that the unique trypanosome SL RNA cap may be required at some point in the assembly of the trans-spliceosome. However, this interpretation is not clear, since it is possible that, as with other snRNAs, the cap could serve to localize the trypanosome SL RNA to the nucleus. Until the pathway of SL RNP assembly is worked out or a trypanosome cell free system is established this will remain an open question. Nevertheless, the enzymes that catalyze cap modification in... 

The first complete structural characterization of a GPI, achieved by Ferguson and coworkers in 1988, was of the T. brucei variant surface glycoprotein (VSG) anchor [9]. This study was assisted by the fact that the African trypanosome system exhibits abundant VSG (ca. 10 copies per cell) [10], which also facilitated the development of the first cell-free... 

The conversion of giycerol-3-phosphate (G-3-P) into dihydroxyacetone phosphate (DHAP) in glycosomes generates reducing equivalents, which enter the mitochondria and convert molecular oxygen into water. This respiratory reaction takes place in the presence of the glycerol-3-phosphate oxidase (glycerolphosphate oxidase, GPO) system. It is a complex enzyme system, which is unique to salivarian trypanosomes this is not found in mammalian cells [7]. Further, GPO is cytochrome free and is bound to the inner membrane of mitochondria (Chart 2). 

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