1. Temperature: Enzymes have an optimal temperature range at which they function best.

* High temperatures disrupt the weak bonds (hydrogen bonds, van der Waals interactions) that maintain the enzyme's three-dimensional structure. This unfolding disrupts the active site, rendering the enzyme non-functional.

* Extremely low temperatures can also cause denaturation, although this is less common. While low temperatures slow down enzyme activity, they don't necessarily cause irreversible damage.

2. pH: Enzymes also have an optimal pH range.

* Extreme pH values (both very acidic and very basic) can disrupt the ionic bonds that hold the enzyme's structure together. This can change the shape of the active site and prevent the enzyme from binding to its substrate.

In addition to these two primary factors, other factors can also contribute to enzyme denaturation, including:

* High salt concentrations: Can disrupt the ionic bonds within the enzyme structure.

* Heavy metal ions: Can bind to the enzyme and alter its structure.

* Organic solvents: Can disrupt the hydrophobic interactions that stabilize the enzyme's structure.

It's important to remember that denaturation is often a reversible process. If the denaturing conditions are removed, the enzyme may be able to refold back to its original shape and regain its function. However, if the denaturation is severe, the enzyme may be irreversibly damaged.