Lipid metabolism — Flashcards

Flashcard 281: Fatty acyl-carnitine is transported from the intermembrane space into the mitochondrial matrix via the _____ transporter

Answer: Carnitine-acylcarnitine translocase

Extra: The **carnitine shuttle** involves: 1. **CPT I:** Located on the outer mitochondrial membrane; converts Acyl-CoA to Acyl-carnitine. 2. **Carnitine-acylcarnitine translocase:** Located on the inner mitochondrial membrane; transports Acyl-carnitine into the matrix in exchange for carnitine. 3. **CPT II:** Located on the inner mitochondrial membrane; converts Acyl-carnitine back to Acyl-CoA for beta-oxidation.

Flashcard 282: Primary carnitine deficiency is characterized by muscle weakness and hypotonia, which is provoked by prolonged _____ (especially if fasting)

Answer: exercise

Flashcard 283: Thromboxane A2 (TXA2) is synthesized by the platelet enzyme _____

Answer: cyclooxygenase-1 (COX-1) (specific)

Flashcard 284: Which apolipoproteins (4) do chylomicrons express on their surface? _____

Answer: Apolipoproteins A-I, B-48, C-II, and E

Flashcard 285: PGI2, PGE2, PGF2-alpha, and thromboxane A2 are synthesized from arachidonic acid by _____.

Answer: Cyclooxygenase (COX-1 and COX-2)

Flashcard 286: Thromboxane A2 is synthesized within platelets by the enzyme COX-_____

Answer: 1

Flashcard 287: What substrate accumulates in the lysosomes of a patient with Fabry disease? _____

Answer: Ceramide trihexoside (globotriaosylceramide)

Flashcard 288: What substrate accumulates in the lysosomes of a patient with Tay-Sachs disease? _____

Answer: GM2 ganglioside

Flashcard 289: Which lysosomal storage disease is characterized by a cherry red spot on the macula and no hepatosplenomegaly? _____

Answer: Tay-Sachs disease

Flashcard 290: Carnitine acyltransferase-1 (CPT-1) is regulated via negative feedback by _____

Answer: malonyl CoA