Use of genetically prepared enzyme conjugates in lactose and galactose analyses

Genetically prepared enzyme conjugates were used in soluble enzyme assays for determination of lactose and galactose with spectrophotometric, fluorimetric, and bioluminometric detection. The use of a bifunctional enzyme in biosensors based on calorimetric detection is also presented. Due to proximity of the enzymes to one another several advantages in the analyses were achieved. The lag phase of coupled enzymatic reactions was reduced and the steady-state rates were increased, which could increase the sensitivity of the assays and decrease the time of analysis.