Biotin Metabolism

This pathway describes biotin recycling in human cells. Biotin, (Vitamin H, Vitamin B7) is an essential nutrient that cannot be synthesized in humans. The best natural sources of biotin in human nutrition are liver, legumes, soybeans, Swiss chard, tomatoes, romaine lettuce, carrots, almonds, eggs, onions, cabbage, cucumber, cauliflower, goat’s milk, cow’s milk, raspberries, strawberries, halibut, oats, and walnuts. Biotin is recycled in cells through a simple cycle that involves conjugation to lysine (forming biocytin), followed by cleavage into biotin and lysine followed by the formation of a biotinyl-AMP intermediate in the mitochondria which can be conjugated to lysine again.