Oxygen Consuming Enzymes

The video tutorial explains three types of oxygen-consuming enzymes: oxidases, monooxygenases, and dioxygenases. Oxidases use molecular oxygen without incorporating it into the substrate, expelling it as water. Monooxygenases, also known as hydroxylases, incorporate one oxygen atom into the substrate, forming a hydroxyl group, while the other is expelled as water. Dioxygenases incorporate both oxygen atoms into the substrate. The tutorial highlights the importance of understanding enzyme nomenclature and the roles of cytochrome P-450 enzymes.

What is the primary characteristic of oxidase enzymes?

• They expel both oxygen atoms as water.

• They incorporate one oxygen atom into the substrate.

• They do not use molecular oxygen.

• They incorporate both oxygen atoms into the substrate.

Which of the following is another name for monooxygenases?

• Peroxidases

• Hydroxylases

• Dioxygenases

• Oxidases

What is the role of NADPH in the function of monooxygenases?

• It provides the necessary electrons for the reaction.

• It is not involved in the reaction.

• It is a byproduct of the reaction.

• It is converted into NADH.

Which enzyme is an example of a cytochrome P-450 monooxygenase?

• Catalase

• Tryptophan dioxygenase

• Aldosterone synthase

• Cytochrome c oxidase

What distinguishes dioxygenases from monooxygenases?

• Dioxygenases expel both oxygen atoms as water.

• Dioxygenases incorporate both oxygen atoms into the substrate.

• Dioxygenases incorporate one oxygen atom into the substrate.

• Dioxygenases do not use molecular oxygen.

What is the product formed when tryptophan is processed by tryptophan dioxygenase?

• N-formylkynurenine

• Aldosterone

• Hydroxylated tryptophan

• Water

How many oxygen atoms are incorporated into the substrate by dioxygenases?

• Three

• Two

• One

• Zero