Possible Interaction: Histidine and Phenylalanine

“An apparent heterogeneity in the interaction between histidine and phenylalanine in the constant-ratio test is probably explained by the role of the Ly+ system in histidine uptake expected for the cationic form of histidine even at pH 7.4.”

“It catalyzes antiport of His and some neutral amino acids such as Ile, Leu, Val, Cys, Met, Gln and Phe thus being involved in amino acid metabolism.”

“Mutagenesis of phenylalanine at position 383 in the hydrophobic interface to histidine (F383H) prevented the biosynthesis of the receptor, indicating that the orientation of helix 8 is important for receptor biosynthesis.”

“Intravenous administration of essential amino acids and histidine during the last 4 h of dialysis increased in muscle the total free amino acids, the ratio of essential to non-essential amino acids and the valine and phenylalanine concentrations.”

“Addition of 0-5-1 -o mM histidine stimulated growth but addition of 02 mM phenylalanine , methionine or valine decreased longevity markedly.”

“Feeding diets containing additional methionine and phenylalanine to protein-depleted rats caused a fall in concentration of the group of amino acids (leucine, isoleucine, valine and histidine ) limiting growth.”

“ Histidyl-phenylalanine was found to be about 100-fold as potent as the commonly used specific histidine decarboxylase inhibitor α-methyl histidine.”

“The results showed that in cultures from both rat strains (1) serum-, basic fibroblast growth factor (bFGF)- and thrombin-induced DNA synthesis were … in a concentration-dependent manner; (3) L-phenylalanine inhibited serum-induced proto-oncogene c-fos and c-myc expression; (4) L-tyrosine, L-histidine … L-phenylalanine.”

“A 20-fold excess of unlabeled leucine, isoleucine, methionine, valine, alanine, lysine, histidine , phenylalanine, and glutamine inhibited uptake of leucine and phenylalanine , and six of these amino acids inhibited uptake of alanine, by more than 50% both in the presence and absence of a potassium ion gradient.”

“The treatment with 1.0 and 1.5 g/kg but not 0.5 g/kg of L-histidine significantly decreased the brain levels of tyrosine, phenylalanine and some other amino acids 1 hr later.”