Which of the following statements are true about enzyme inhibitors?

• A. Competitive inhibitors change the slope of the Lineweaver-Burk line but not the y-intercept.
• B. Noncompetitive inhibitors are a type of mixed inhibitor.
• C. Uncompetitive inhibitors change Km & Vmax in a way to create a parallel Lineweaver-Burk line.
• D. Noncompetitive inhibitors result in lines with increasing [I] to share the same x-intercept.
• E. All the above are true.

Answer: (E)

Verified step by step guidance

1. Understand the role of enzyme inhibitors: Enzyme inhibitors are molecules that bind to enzymes and decrease their activity. They can be classified into different types based on their mechanism of action.
2. Examine competitive inhibitors: Competitive inhibitors bind to the active site of the enzyme, competing with the substrate. In a Lineweaver-Burk plot, they increase the slope but do not affect the y-intercept, as they do not change Vmax but increase Km.
3. Explore noncompetitive inhibitors: Noncompetitive inhibitors bind to an allosteric site, not the active site, and can affect both Km and Vmax. They are a type of mixed inhibitor, as they can bind to the enzyme whether or not the substrate is present.
4. Analyze uncompetitive inhibitors: Uncompetitive inhibitors bind only to the enzyme-substrate complex, decreasing both Km and Vmax proportionally, resulting in a parallel shift of the Lineweaver-Burk plot.
5. Consider the effect of noncompetitive inhibitors on the Lineweaver-Burk plot: Noncompetitive inhibitors result in lines with increasing inhibitor concentration ([I]) that share the same x-intercept, as they do not affect Km.