Amino Acids

9 essential amino acids

Phe, Val, The, Trp, Ile, Met, Hist, Lys, Leu

6 conditionally essential

Arg, Cyc, Gly, Glu, Pro, Tyr

• catalyzes reversible transfer of α-NH₃⁺ from alanine to α-ketoglutarate to form pyruvate (keto acid) and glutamate

Alanine aminotransferase (ALT)

catalyzes reversible transfer of α-NH₃⁺ from aspartate to α-ketoglutarate to form oxaloacetate (keto acid) and glutamate

Aspartate aminotransferase (AST)

Detoxify ammonia by converting it to urea (excreted in urine)

urea cycle

Energy cost of laundry

3 ATP