Induced fit theory is a more acceptable mechanism than the lock and key model for enzyme kinetics because it considers the dynamic nature of enzymes and their interactions with substrates. The lock and key model suggests that the enzyme's active site is rigid and complementary in shape to the substrate, allowing for a perfect fit. However, this model fails to account for the flexibility and adaptability of both the enzyme and substrate.
On the other hand, the induced fit theory proposes that the active site of the enzyme undergoes conformational changes upon substrate binding, resulting in a better fit and increasing the catalytic efficiency. This model considers the dynamic interactions between the enzyme and substrate, and it can explain various phenomena, such as substrate specificity, cooperativity, and enzyme regulation.
Moreover, experimental evidence supports the induced fit theory. X-ray crystallography studies have revealed conformational changes in the active site of enzymes upon substrate binding. Additionally, site-directed mutagenesis experiments have shown that changing amino acids in the active site can affect substrate binding and catalysis, supporting the idea of dynamic interactions between the enzyme and substrate.
Overall, the induced fit theory is a more comprehensive and accurate model that accounts for the dynamic nature of enzyme-substrate interactions and is widely accepted in the field of enzyme kinetics.