Molecular characterization of the cis-prenyltransferase of Giardia lamblia.

ABSTRACT: Giardia lamblia, the protist that causes diarrhea, makes an Asn-linked-glycan (N-glycan) precursor that contains just two sugars (GlcNAc(2)) attached by a pyrophosphate linkage to a polyprenol lipid. Because the candidate cis-prenyltransferase of Giardia appears to be more similar to bacterial enzymes than to those of most eukaryotes and because Giardia is missing a candidate dolichol kinase (ortholog to Saccharomyces cerevisiae SEC59 gene product), we wondered how Giardia synthesizes dolichol phosphate (Dol-P), which is used to make N-glycans and glycosylphosphatidylinositol (GPI) anchors. Here we show that cultured Giardia makes an unsaturated polyprenyl pyrophosphate (dehydrodolichol), which contains 11 and 12 isoprene units and is reduced to dolichol. The Giardia cis-prenyltransferase

SUBMITTER: Grabinska KA 

PROVIDER: S-EPMC2900897 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature