Fatty acids, binding protein branched chain

The ability of L-tryptophan to bind to plasma proteins of the blood and circulate as free and bound tryptophan is a unique feature for an amino acid. This binding is affected by and competes with other compounds that bind plasma proteins, such as nonesterified fatty acids (NEFA) and certain drugs. This relationship in blood affects its transport from the blood to the brain because only the free tryptophan is transplanted through the blood-brain barrier. Free tryptophan s concentration in blood in relation to other amino acids, particularly branched-chain amino acids (BCAA), affects its transport to the brain. 

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