Which mechanisms do enzymes use to catalyze a reaction?

Prepare for the Foundations of Biology Exam 1. Dive into key biological concepts with multiple choice questions, hints, and explanations. Ace the exam with our efficient study methods!

Enzymes speed reactions by using more than one catalytic strategy. One common approach is orienting substrates so their reactive parts are aligned and in the right distance to react, which raises the chance that a reaction will occur when they meet. Another important strategy is induced fit: when the substrate binds, the enzyme changes shape in a way that brings catalytic groups into the proper arrangement and stabilizes the transition state, lowering the activation energy. Often, enzymes employ more than one tactic, and even more catalytic methods exist, such as stabilizing charged states or forming transient covalent interactions with the substrate.

Because both orienting substrates and inducing fit contribute to catalysis, the best answer is that all of the above mechanisms can be involved. The idea that a single mechanism accounts for all reactions isn’t accurate, since enzymatic catalysis uses diverse strategies depending on the substrate and reaction.