Post-translational modifications (PTMs) play a big role in how enzymes work and are controlled. Here’s a simple breakdown:

1. Types of PTMs:

   • Phosphorylation: This is when about 30% of proteins get a special group added to them. This can either turn an enzyme on or off, making its activity change by up to 100 times!
   • Acetylation: This change helps manage metabolic enzymes. It can also affect how stable and effective these enzymes are.
   • Glycosylation: Around 50% of proteins undergo this modification. It affects how long enzymes last and how well they work.

2. How They Regulate Enzymes:

   • Allosteric Modulation: PTMs can change the shape of an enzyme. This can affect how fast the enzyme works.
   • Proteolytic Cleavage: Some enzymes need a piece cut off to become active. This is important for 80% of regulatory enzymes.

3. Effects on Enzyme Function:

   • Changes in KM and Vmax: PTMs can change the Michaelis constant (KM) and maximum velocity (Vmax). This means they can affect how easily enzymes grab their target and how fast reactions happen.

In summary, PTMs are really important for keeping enzymes working just right and managing how metabolism functions in living things.