The de novo and salvage pathways of GDP-mannose biosynthesis are both sufficient for the growth of bloodstream-form Trypanosoma brucei.

ABSTRACT: The sugar nucleotide GDP-mannose is essential for Trypanosoma brucei. Phosphomannose isomerase occupies a key position on the de novo pathway to GDP-mannose from glucose, just before intersection with the salvage pathway from free mannose. We identified the parasite phosphomannose isomerase gene, confirmed that it encodes phosphomannose isomerase activity and localized the endogenous enzyme to the glycosome. We also created a bloodstream-form conditional null mutant of phosphomannose isomerase to assess the relative roles of the de novo and salvage pathways of GDP-mannose biosynthesis. Phosphomannose isomerase was found to be essential for parasite growth. However, supplementation of the medium with low concentrations of mannose, including that found in human plasma, relieved this dependen

SUBMITTER: Kuettel S 

PROVIDER: S-EPMC3412276 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature