Abstract This is our sixth consecutive study carried out in an order to collect experimental evidence on the impact of heavy water (D 2 O) spontaneous peptidization proteinogenic α -amino acids and this time it L -histidine ( -His). Scientists have not yet achieved a full consensus regarding source very important amino acid human mammalian tissues, particular question rather contradictory answe...

The presence of several naturally occurring amino acids in the serosal bath of toad urinary bladder significantly alters the hydrosmotic response of this tissue to vasopressin. We found that histidine, glutamate, and lysine increase vasopressinstimulated water flow by 75%, 60%, and 43%, respectively. In contrast, alanine did not alter vasopressin-stimulated water flow, whereas glutamine decreas...

The inactivation of E. coli asparaginase by 2,3-butanedione studied with L-asparagine and diazooxonorvaline as substrates obeys pseudo first order kinetics. Activity losses are linear with respect to arginine and histidine modification, with complete inactivation being correlated with alteration of one arginine and one histidine per subunit. The rate of inactivation of the enzyme was reduced in...

A study was made of how the catabolism of a carbon and energy source is affected by the biosynthetic demands of growing bacterial cells. Cultures of Aerobacter aerogenes in l-histidine medium were grown in a chemostat at rates determined by the supply of either sulfate or a required amino acid, l-arginine. It was discovered that the rate at which these cells grow under a biosynthetic restrictio...

Morphology-controlled synthesis of CdS can significantly enhance the efficiency of its photocatalytic hydrogen production. In this study, a novel three-dimensional (3D) flower-like CdS is synthesized via a facile template-free hydrothermal process using Cd(NO3)2•4H2O and thiourea as precursors and L-Histidine as a chelating agent. The morphology, crystal phase, and photoelectrochemical performa...

In highly alkaline aqueous solutions, cobalt(I1) forms violet, tetrahedral, bis complexes with L-histidine, histamine, and N-acetyl-L-histidine. Imidazole similarly forms a tetrakis complex. Generation of the tetrahedral complexes is dependent on deprotonation of the imidazole ring pyrrole nitrogen for the L-histidine, histamine, and imidazole complexes, and on two amide hydrogen ionizations fo...

Studies in vitro have shown that L-histidine increases the hydroosmotic response to vasopressin. We examined whether this phenomenon occurs also in vivo. Homozygous Brattleboro rats (di/di) were fed a regular diet (0.5% histidine) or a diet enriched with histidine and received 1 ng of 1-deamino-8-D-arginine vasopressin (dDAVP) daily. Addition of histidine (1% by weight) increased post-dDAVP uri...

Three different imidazole compounds are known to induce the enzymes that degrade histidine in Aerobackr aerogenes (l-4). Two of them, histidine and urocanate, are, respectively, the substrate and product of the first enzyme, histidine ammonialyase; the third, imidazolepropionate, is a nonmetabolizable analogue of urocanate. Previous studies with this system did not discriminate between the poss...