Disease relevance of Tyr-Ala

• Four variants of human beta globin in which the Trp at position 37 has been replaced with a Tyr, Ala, Gly, or Glu have been expressed in Escherichia coli [1].
• For individual amino acids, in early colorectal cancer patients, the plasma level of most essential amino acids and non-essential amino acids decreased (significantly in Tyr, Ala, Met, Phe and Thr) [2].

High impact information on Tyr-Ala

• The five residues of the galago M/LWS pigment are Ala, His, Tyr, Ala, and Ala, respectively, and its peak absorption spectra (lambda(max)) was measured to be 539 nm, which is virtually identical to the expected value from the rule (538 nm), showing that the five-sites rule holds for this prosimian [3].
• Solution NMR evidence for a cis Tyr-Ala peptide group in the structure of [Pro93Ala] bovine pancreatic ribonuclease A [4].
• GIP1-42 is a substrate of the circulating enzyme dipeptidyl peptidase IV, which removes the N-terminal peptide Tyr-Ala resulting in the inactive polypeptide GIP3-42 [5].
• The three DL-amino acid residues (Tyr, Ala and Gly) in [L-Ala2]-leucine-enkephalin and [D-Ala2]-leucine-enkephalin were perfectly identidied with the autoanalysis [6].
• The binding of the radioligand to cardiac membranes was inhibited by unlabeled Tyr Ala hexare lin and hexarelin as well as by GHRP-6, GHRP-1 and GHRP-2 but not by MK-677, a non peptidyl GHRP analog [7].

Associations of Tyr-Ala with other chemical compounds

• While elastase I cleaves mostly Ala-Ala and also Ala-Gly bonds, elastase II hydrolyzes Leu-Ala, Leu-Gly, Phe-Ala, Phe-Gly and Tyr-Ala, Tyr-Gly bonds [8].

Gene context of Tyr-Ala

• On the other hand, DPPIV mediated cleavage of the N-terminal His-Ala or Tyr-Ala dipeptides from circulating incretin hormones like, glucagon-like peptides (GLP)-1 and -2, gastric inhibitory polypeptide (GIP), all members of the enteroglucagon/GRF superfamily, results in their biological inactivation in vitro and in vivo [9].
• Bovine GRF is a substrate for DPP-IV and is rapidly degraded by the enzyme via removal of its N-terminal Tyr-Ala [10].

Analytical, diagnostic and therapeutic context of Tyr-Ala

• Analysis by HPLC showed that chymotrypsin cleaved only the dephosphorylated substrate at the Tyr-Ala bond [11].
• Copper(II) complexes of L-amino acylamides (Phe, Val, Tyr, Ala) when added to the eluent (water-acetonitrile) in reversed-phase high-performance liquid chromatography (C18) are able to perform enantiomeric separation of dansylamino acids [12].

References