Essential vs. non-essential amino acids — Flashcards

Flashcard 1: Only _____-amino acids are found in proteins

Answer: L

Flashcard 2: Which amino acids (2) are the precursors to catecholamines and melanin? _____

Answer: Tyrosine, Phenylalanine

Flashcard 3: Most disorders of the urea cycle require _____ as an essential amino acid, particularly during episodes of hyperammonemia

Answer: arginine

Flashcard 4: What amino acid becomes essential in patients with phenylketonuria? _____

Answer: Tyrosine

Flashcard 5: What amino acids (3) are necessary for purine synthesis? _____

Answer: Glycine, Aspartate, Glutamine

Flashcard 6: Which amino acids (2) are ketogenic? _____

Answer: Leucine, Lysine

Flashcard 7: What stainable protein is abundant in astrocytes?

Answer: GFAP

Flashcard 8: What enzyme converts pyruvate to alanine?

Answer: alanine aminotransferase (ALT)

Flashcard 9: Role of myeloperoxidase in neutrophils:

Answer: Plays a role in respiratory burst (catalyzes formation of HOCl from H2O2)

Extra: Myeloperoxidase (MPO) is found in the azurophilic granules of neutrophils (PMNs). During the respiratory burst, it converts Hydrogen Peroxide (H2O2) and Chloride ions into Hypochlorous acid (HOCl - bleach), which is a potent bactericidal agent.

Flashcard 10: What reaction is catalyzed by superoxide dismutase during the respiratory burst?

Answer: Conversion of Superoxide ($O_2^-$) to Hydrogen peroxide ($H_2O_2$)

Extra: Superoxide dismutase (SOD) neutralizes superoxide radicals. Reaction: 2O2- + 2H+ -> H2O2 + O2. Clinical Pearl: Mutations in superoxide dismutase 1 (SOD1) are associated with Amyotrophic Lateral Sclerosis (ALS).