A Novel Xylosylphosphotransferase Activity Discovered in Cryptococcus neoformans

Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Journal of Biological Chemistry (Impact Factor: 4.57). 10/2009; 284(52):36118-27. DOI: 10.1074/jbc.M109.056226
Source: PubMed


Cryptococcus neoformans is a fungal pathogen that causes serious disease in immunocompromised individuals. The organism produces a distinctive polysaccharide capsule that is necessary for its virulence, a predominantly polysaccharide cell wall, and a variety of protein- and lipid-linked glycans. The glycan synthetic pathways of this pathogen are of great interest. Here we report the detection of a novel glycosylphosphotransferase activity in C. neoformans, identification of the corresponding gene, and characterization of the encoded protein. The observed activity is specific for UDP-xylose as a donor and for mannose acceptors and forms a xylose-alpha-1-phosphate-6-mannose linkage. This is the first report of a xylosylphosphotransferase activity in any system.

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