Mannose-6-phosphate isomerase

MANNOSE-6-PHOSPHATE ISOMERASE MAN NOSE-1-PHOSPHATE GUANYLYL-TRANSFERASE... 

D-Mannose 1-phosphate, interconversion to D-mannose 6-phosphate, PHOSRHOMANNOMUTASE MANNOSE-6-PHOSPHATE ISOMERASE D-Mannose residues,... 

These enzymes vary widely in secondary and tertiary structure.1273 Mannose-6-phosphate isomerase is a 45 kDa Zn2+-containing monomer. The larger 65 kDa L-fucose isomerase, which also acts on D-arabinose, is a hexameric Mn2+-dependent enzyme.1273 L-Arabinose isomerase of E. coli, which interconverts arabinose and L-ribulose, is a hexamer of 60-kDa subunits128 while the D-xylose isomerase of Streptomyces is a tetramer of 43-kDa subunits.129 The nonenzymatic counterpart of the isomerization catalyzed by the enzyme is the base-catalyzed Lobry deBruyn-Alberda van Ekenstein transformation (Eq. 13-25).130... 

Mannoprotein of yeast cell walls 185 Mannose (Man) 161s, 163s Mannose-6-phosphate 185 Mannose-6-phosphate isomerase 693 MAP kinase cascade 576-578 figure 579... 

There is no obvious pattern in the metal ion requirements of enzymes that catalyze proton transfer at carbon. For example, mannose 6-phosphate isomerase [85] is a metalloenzyme while triosephosphate isomerase [86] and glucose 6-phosphate... 

GDP-Man regeneration system starting from Man-l-P has been report by Wong s gcoup(9). As the Fru-6-P is inexpensive to obtain, we developed a new regeneration padiway from Fru-6-P with all recombinant enzymes. As shown in Scheme 4, the cycle comprises of three key enzymes D-mannose-6-phosphate isomerase (PMI, EC 5.3.1.8), phosphomannomutase (PMM, EC 5.4.2.S) and... 

Tissue was homogenised with an equal volume of buffer (2 ml Tris-HCl (pH 8.0), 0.1 ml mercaptoethanol, 10 g sucrose, and 25 mg NADP per 100 ml H2O - adjusted to pH 7.2 with HCl). Electrophoresis was performed on cellulose acetate plates (Titan III Helena Laboratories). A preliminary survey of 42 enzymes detected four enzyme loci, coding for four different enzyme systems that were polymorphic and consistently resolvable. These enzymes were used for the analysis and were as follows (abbreviation and enzyme commission number in parentheses) hexokinase (HK, E.C. 2.7.1.1), mannose-6-phosphate isomerase (MPI, E.C. 5.3.1.8), 6-phosphogluconate dehydrogenase (6PGD, E.C. 1.1.1.44), and phosphoglucose isomerase (PGI, E.C. 5.3.1.9). 

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