Just with this bit:
Why does changing the pH from the optimum value cause a decrease in the activity of the enzyme?
•
the tertiary structure of the enzyme changes with change in pH• change in [H+] may change the charge on side chain groups (thus affecting interactions between Z groups that determine the tertiary structure)
• the enzyme is denatured so the shape of the active site changes. (2010)
I've seen on other parts of the chem forum that pH may disrupt the secondary structure as well, and I've also seen people who say that it does not so I'm a bit lost. If this comes up on Tuesday I'll use this answer if its in a similar context (aka denaturing enzymes)

, I was just wondering if someone could explain exactly why the secondary structure is/isn't disrupted by pH, just in case VCAA frame the question so it doesn't relate to the functioning of enzymes?