Enkephalines

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Page ID: 79355

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Enkephalins (penta-peptides) have recently been discovered as regulators of nerve impulses involving pain in the brain. Apparently these peptides act as natural analgesics (pain-killers) and their action mimics that of morphine and other opiates. At present it is thought that the morphine-like effects are due to aromatic side chains on phenylanine and tyrosine which mimic a similar sturcture on morphine. Apparently, it does not make much difference whether the enkephalin contains methionine or leucine at the acid end of the peptide. The primary structures are:

methionine-enkephaline: tyr - gly - gly - phe - met
leucine-enkephalin: tyr - gly - gly - phe - leu

QUES. Write the peptide structure for methionine-enkephalin. Enkephalin - Met - Chime in new window

Quiz:Which amino acid is the N-terminal one?
Which amino acid is the C-terminal one?

Contributors and Attributions

Charles Ophardt (Professor Emeritus, Elmhurst College); Virtual Chembook