Exam 23: Protein Turnover and Amino Acid Catabolism

In the transaminase reaction, pyridoxal phosphate is converted into __________________ when the first amino acid is converted into an $\alpha$ -keto acid.

Describe the structure and function of the 26S proteasome.

Which amino acids supply carbons as succinyl CoA for eventual entry into metabolism?

Explain the cause of PKU, and give the structure of the abnormal metabolite that accumulates from which this condition gets its name.

What cofactor is required by phenylalanine hydroxylase?

What enzyme catalyzes an oxidative deamination using either NAD⁺ or NADP⁺?

In the degradation of amino acids other than Thr or Ser, the amino nitrogens can eventually become the amino group of ___________________.

What product of the first step of methionine degradation is an important methyl group donor?

Four of the five enzymes in the urea cycle are evolutionarily related to enzymes found in

Describe the glucose-alanine cycle and its significance in amino acid metabolism.

Describe how the urea cycle is linked to the citric acid cycle.

The half-life of a cytosolic protein is primarily determined by the

Which of the following is an allosteric activator of mammalian carbamoyl phosphate synthetase?

Nitrogen is transported from muscle to liver in the form of ______________.

What is the function of the acidic environment in the stomach?

What is the fate of sulfur in the metabolism of cysteine?

What are some types of enzyme-catalyzed reactions that require pyridoxal phosphate as a coenzyme?

In the urea cycle, the second nitrogen of urea enters the cycle in the form of which of the following metabolites?

In the urea cycle, the carbon skeleton of aspartate is preserved as

Which of the following is a product of the transamination of aspartate and $\alpha$ -ketoglutarate?