PHOSPHATE AND MANNOSE TRANSFER FROM GUANOSINE DIPHOSPHATE MANNOSE TO YEAST MANNAN ACCEPTORS

A particulate enzyme isolated from Hansenula holstii catalyzes the transfer of 14C-mannose from guanosine diphosphate 14C-mannose and of 32P-phosphate from β-32P-guanosine diphosphate mannose to endogenous acceptor molecules. The 32P-product is solubilized with Tris buffer, excluded from Sephadex G-50 and precipitated with Fehling's reagent.32P-Mannose 6-phosphate is recovered from acid hydrolyzates. Mild acid hydrolysis liberates newly incorporated mannose residues and allows the 32P-phosphate to be released as inorganic phosphate by phoshomonoesterase. The synthesis of a 1, 6′-phosphodiester linkage between 2 mannose residues is proposed. © 1969.