Enzymatic determination of D-mannose in serum.
A new and simple enzymatic assay for measuring D-mannose in serum is described. Endogenous glucose is eliminated from serum by use of glucose oxidase (EC 1.1.3.4) and catalase (EC 1.11.1.6). D-Mannose concentration is calculated from the increase in NADH formation after mannosephosphate isomerase (EC 5.3.1.8) is added. This increase is a result of coupling the following series of enzymes: hexokinase (EC 2.7.1.1), glucosephosphate isomerase (EC 5.3.1.9), and glucose-6-phosphate dehydrogenase (EC 1.1.1.49, NAD+-dependent). The study included subjects who were healthy volunteers and patients with suspected or proven fungal infections.
D002177:Candidiasis / Q000097:blood*; D002374:Catalase; D005949:Glucose Oxidase; D006801:Humans; D008358:Mannose / Q000097:blood*; D009243:NAD / Q000032:analysis; D013056:Spectrophotometry, Ultraviolet
D009243:NAD; D005949:Glucose Oxidase; D002374:Catalase; D008358:Mannose