Overexpression of an enzyme in a linear pathway generally leads to
Flux through linear biosynthetic pathway depends on enzyme abundance catalytic efficiency and substrate availability governed by Michaelis-Menten kinetics. Overexpressing gene encoding rate-limiting enzyme increases Vmax for that conversion accelerating substrate to product transformation provided upstream supply not limiting and feedback inhibition weak. Engineered strains carrying multicopy plasmids or strong promoters often show elevated end product titre illustrating dosage effect on metabolism. In natural regulation overexpression may be compensated by allosteric inhibition yet textbook m
Ref: Griffiths et al., Introduction to Genetic Analysis, 12th ed., Chapter 14: Gene Dosage and Metabolic Flux Increase
