biostudies-literatureUnknown103(25)Sernee MFInfective stages of the protozoan parasite Leishmania spp. accumulate a class of beta-1,2-mannan oligosaccharides as their major carbohydrate reserve material. Here, we describe the biosynthesis of Leishmania mannan. Mannan precursors were identified by metabolic labeling of Leishmania mexicana promastigotes with [(3)H]mannose. Label was initially incorporated into a phosphomannose primer and short phosphorylated beta-1,2-mannan oligomers that were two to five residues long. Analysis of the mannan primer by Fourier transform ion-cyclotron resonance MS and various enzymatic and chemical treatments and comparison with authentic mannose (Man) phosphates indicated the presence of Man-alpha-1,4-cyclic phosphate. This primer was synthesized from Man-6-phosphate by means of Man-1-phosphate in a cProceedings of the National Academy of Sciences of the United States of America9458-63https://www.ebi.ac.uk/biostudies/studies/S-EPMC1480429biostudies-literatureLeishmania beta-1,2-mannan is assembled on a mannose-cyclic phosphate primer.PMC1480429Sernee MFDinev ZWilliams SJRalton JEO'Hair RAMcConville MJKhairallah GNfalseLeishmania beta-1,2-mannan is assembled on a mannose-cyclic phosphate primer.Infective stages of the protozoan parasite Leishmania spp. accumulate a class of beta-1,2-mannan oligosaccharides as their major carbohydrate reserve material. Here, we describe the biosynthesis of Leishmania mannan. Mannan precursors were identified by metabolic labeling of Leishmania mexicana promastigotes with [(3)H]mannose. Label was initially incorporated into a phosphomannose primer and short phosphorylated beta-1,2-mannan oligomers that were two to five residues long. Analysis of the mannan primer by Fourier transform ion-cyclotron resonance MS and various enzymatic and chemical treatments and comparison with authentic mannose (Man) phosphates indicated the presence of Man-alpha-1,4-cyclic phosphate. This primer was synthesized from Man-6-phosphate by means of Man-1-phosphate in a c2006-01-01T00:00:00Z2006 Jun2025-04-19T08:42:28.234Z2019-03-27T01:45:29ZS-EPMC14804291676665010.1073/pnas.0603539103