Enzyme Factors and Inhibition: Tyrosinase Activity and Environmental Effects

What are enzymes?

Biocatalysts made of protein that increase the rate of chemical reactions.

What is the role of enzymes in metabolism?

Enzymes catalyze reactions by lowering the activation energy needed for the reaction to occur.

What is an enzyme-substrate complex?

The complex formed when an enzyme binds to a substrate molecule.

What is the active site of an enzyme?

The site on the enzyme where the substrate binds.

What is a substrate?

The substance that an enzyme acts upon to produce a product.

What is an inhibitor?

Substances that interfere with the function of the enzyme.

What is competitive inhibition?

When an inhibitor competes with the substrate for binding to the active site of the enzyme.

How can competitive inhibition be overcome?

By increasing the substrate concentration.

What is non-competitive inhibition?

When an inhibitor binds to a site other than the active site, altering the enzyme's shape and function.

What factors affect enzyme activity?

Temperature, pH, substrate concentration, enzyme concentration, and the presence of inhibitors.

What happens to enzymes at extreme temperatures or pH levels?

They can become denatured, losing their three-dimensional shape and functionality.

What is the significance of the enzyme tyrosinase?

It is involved in the production of melanin and is found in both animals and plants.

What is the substrate for tyrosinase?

Pyrocatechol.

What is the product formed by the reaction of tyrosinase with pyrocatechol?

Hydroxyquinone.

How is enzymatic activity quantified in experiments?

By measuring the absorbance of light at 475 nm using a spectrophotometer.

What does a higher absorbance value at 475 nm indicate?

More end products are produced, indicating greater enzymatic activity.

What is the energy of activation?

The energy needed to form the transition state during a chemical reaction.

What is meant by enzyme specificity?

Most enzymes are specific to one substrate and perform one chemical reaction.

What does it mean for an enzyme to be denatured?

The enzyme's three-dimensional shape is disrupted, rendering it inactive.

What is the relationship between enzyme concentration and reaction rate?

Increasing enzyme concentration generally increases the reaction rate, provided substrate is available.

What is the effect of substrate concentration on enzyme activity?

Increasing substrate concentration can increase the reaction rate until the enzyme is saturated.

What is the optimum condition for enzyme activity?

40degrees Celsius and pH 7

What happens to the enzyme after the reaction is complete?

The enzyme is released in its original condition and can catalyze another reaction.

What is the role of the enzyme's active site in catalysis?

It binds the substrate and stresses its bonds, facilitating the conversion to product.

What are the two types of enzyme inhibitors?

Competitive inhibitors and non-competitive inhibitors.

How does a non-competitive inhibitor affect enzyme activity?

It alters the shape of the active site, preventing substrate binding regardless of substrate concentration.