3-Energy, Enzymes, and Metabolism II

What type of enzyme connects monomers together to form a polymer?

Polymerase

What type of enzyme attaches a phosphate group to its substrate?

a kinase

What type of enzyme removes a phosphate group from its substrate?

a phosphatase

What type of enzyme catalyzes an oxidation-reduction reaction?

an oxido-reductase

What type of enzyme catalyzes the hydrolysis of ATP?

an ATPase

What type of enzyme catalyzes a hydrolysis reaction?

a hydrolase

What type of enzyme breaks down nucleic acids?

a nuclease

What type of enzyme breaks down proteins?

a protease

Write out the basic steps of an enzyme catalyzed reaction.

E + S --> ES --> EP --> E + P

What term describes the maximal velocity of a reaction at saturating substrate concentrations?

Vmax

What do we call the concentration of substrate at half Vmax?

the Km

What type of inhibitor binds to an enzyme's active site to inhibit the enzyme?

A competitive inhibitor.

What type of inhibitor binds to a site on the enzyme that is not the active site to inhibit the enzyme?

A Noncompetitive inhibitor.

What two environmental factors can affect enzyme activity?

Temperature and pH

What effect can a change in temperature or pH have on an enzyme that would stop it from functioning?

They could denature the enzyme.

Is the following statement true or false: All enzymes have an optimum temperature range and an optimum pH range.

True

Is the following statement true or false: An enzyme's optimum temperature range and optimum pH range will be the temperature and pH of the environment the enzyme is normally found.

True

What form of enzyme regulation involves a molecule binding to the enzyme at a site that is not the active site to affect the function of the enzyme?

Allosteric regulation

Is allosteric regulation always inhibitory?

No, allosteric regulation can also lead to the activation of an enzyme.

Is allosteric regulation reversible?

Yes

What enzymes are involved in regulating another enzyme's activity through the addition and removal of phosphate groups?

Kinases and phosphatases. Kinases add phosphate groups and phosphatases remove phosphate groups.

If an enzyme is activated by the addition of a phosphate group, then what type of enzyme would activate it?

A kinase.

If an enzyme is activated by the removal of a phosphate group, what type of enzyme would activate it?

A phosphatase.

If an enzyme is activated by the addition of a phosphate group, then what type of enzyme will turn the enzyme off (deactivate it)?

A phosphatase.

If an enzyme is activated by the removal of a phosphate group, then what type of enzyme would turn it off (deactivate it)?

A kinase.

What type of regulation involves the breaking of covalent bonds to turn the enzyme on?

Proteolytic activation.

What type of metabolic pathway breaks molecules down?

Catabolic pathway

What type of metabolic pathway synthesizes molecules?

Anabolic pathway

What type of metabolic pathway tends to release energy?

A catabolic pathway.

What type of energy tends to require the input of energy?

An anabolic pathway.

What is it called when a product of a pathway goes back and inhibits an enzyme that acts earlier in the pathway?

Feedback inhibition

Why is feedback inhibition important?

It prevents over accumulation of the product.