The higher the enzyme concentration in a reaction mixture, the greater the number of active sites available and the greater the likelihood of enzyme-substrate complex formation
As long as there is sufficient substrate available, the initial rate of reaction increases linearly with enzyme concentration
If the amount of substrate is limited, at a certain point any further increase in enzyme concentration will not increase the reaction rate as the amount of substrate becomes a limiting factor
The effect of enzyme concentration on the rate of an enzyme-catalysed reaction