phenylalanine

(noun)

an essential amino acid C9H11NO2 found in most animal proteins; it is essential for growth; the inability to metabolize it leads to phenylketonuria; it is a constituent of aspartame.

Related Terms

Examples of phenylalanine in the following topics:

  • Phenylketonuria (PKU)

    • When PAH activity is reduced, phenylalanine accumulates.
    • Elevated levels of phenylalanine in the blood and detection of phenylketones in the urine is diagnostic.
    • Phenylalanine is a large, neutral amino acid (LNAA).
    • If phenylalanine is in excess in the blood, it will saturate the transporter.
    • Excessive levels of phenylalanine tend to decrease the levels of other LNAAs in the brain.

  • Chemistry of Hormones

    • Monoamine hormones are derived from single aromatic amino acids like phenylalanine, tyrosine, and tryptophan.

  • Cystic Fibrosis

    • The ΔF508 human genome mutation is characterized by the deletion of three base pairs in the CFTR nucleotide sequence, causing the loss of the amino acid phenylalanine located at position 508 .
    • The ΔF508 human genome mutation is characterized by the deletion of three base pairs in the CFTR nucleotide sequence, causing the loss of the amino acid phenylalanine located at position 508.

  • Processing of tRNAs and rRNAs

    • This is a space-filling model of a tRNA molecule that adds the amino acid phenylalanine to a growing polypeptide chain.
    • The amino acid phenylalanine is attached to the other end of the tRNA.

  • Mechanisms of Hormone Action

    • Monoamine: Hormones derived from aromatic amino acids such as phenylalanine, tyrosine, and tryptophan.

  • Secondary & Tertiary Structure of Large Peptides and Proteins

    • The first hydrogen bond (from the N-terminal end) is from the carbonyl group of the alanine to the N-H group of the phenylalanine.
    • Parts of the N-terminal alanine acceptor and the phenylalanine donor also fall within this helical turn, and careful analysis of the structure indicates there are 3.6 amino acid units per turn.

  • RNA and Protein Synthesis

    • A synthetic polyuridine RNA induced synthesis of poly-phenylalanine, so the UUU codon designated phenylalanine.

  • The Primary Structure of Peptides

    • Thus, aspartic acid (Asp) and phenylalanine (Phe) may be combined to make Asp-Phe or Phe-Asp, remember that the amino acid on the left is the N-terminus.