The transport characteristics of L- and D-histidine through the blood-lung barrier were studied in cultured rat lung microvascular endothelial cells (LMECs). L-Histidine uptake was a saturable process. The addition of metabolic inhibitors [2,4-dinitrophenol (DNP) and rotenone] reduced the uptake rate of L-histidine. Ouabain, an inhibitor of Na(+)-K(+)-ATPase, also reduced uptake of L-histidine....

1. The histidine requirement of growing kittens was determined from an experiment in which forty-eight kittens were randomly allocated to six amino acid-based diets supplying: 1.0, 1.5, 2.0, 2.5, 3.0 or 4.5 g histidine base/kg diet. 2. By 48 d it was obvious that 1.0 and 1.5 g histidine/kg diet were grossly inadequate so the kittens receiving these two diets were removed from the experiment. Th...

High-resolution spatiotemporal imaging of histidine in single living mammalian cells faces technical challenges. Here, we developed a series of ratiometric, highly responsive, and single fluorescent protein-based histidine sensors of wide dynamic range. We used these sensors to quantify subcellular free-histidine concentrations in glucose-deprived cells and glucose-fed cells. Results showed tha...

The object was to determine whether the depletion of histidine would have a more marked inhibitory effect on human leukaemia cells than on normal human cells, thus indicating a wider use for enzymes in cancer therapy. Studies of the effect of histidine concentration on cell growth, death, metabolism, protein composition, histidine uptake and utilization by cells were carried out. The medium and...

Mixtures of skim milk and free amino acids were compared as diets for pigs which would allow manipulation of dietary amino acid levels. Piglets gained 208 g/d between 3 and 14 d of age on the skim-milk diet, but replacement of 600 g/kg of the dietary nitrogen with free amino acids reduced growth rate to 148 g/d. Supplementation of a lysine-deficient diet with lysine reduced the catabolism of [1...

Dietary histidine has been shown to elevate circulating free histidine and plasma histamine concentration in murine models as much as 6fold. Bladder mastocytosis is a hallmark of feline interstitial cystitis, and histidine is stored in mast cells and converted to histamine for signaling and inflammation by the enzyme histidine decarboxylase. Elevated dietary histidine may represent a risk facto...

Biophysical and biochemical instability of therapeutic proteins in the solution state may necessitate development products solid form, due to their enhanced stability. Lyophilization is a widely used method ensure dry stabilization biological products. A commonly encountered issue pH shifts that can occur undesired crystallization buffer component, resulting loss protein activities. However, it...

Histidine-rich glycoprotein, and alpha 2-glycoprotein in human plasma, has been shown to interact with heparin, with the high-affinity lysine-binding site of plasminogen, with divalent cations, and is associated with the rosette formation between erythrocytes and lymphocytes. A specific enzyme-linked immunosorbent assay for histidine-rich glycoprotein has been developed and used to demonstrate ...