An enzyme catalyzing the synthesis of L-cystathionine from the succinyl ester of L-homoserine and L-cysteine was isolated from a Salmonella mutant blocked in another step of methionine synthesis, and derepressed for cystathionine y-synthetase formation. The approximate molecular weight of the enzyme was 155,000 and it was unchanged after removal of tightly bound pyridoxal phosphate. In the abse...

The endotelio- and cardioprotective effects of vitamin B6 (2 mg/kg) folic acid (0.2 upon modeling methionine-induced hyperhomocysteinemia via methionine intragastric administration at a dose 3 g/kg were studied. It was shown that the combined use allows on background significant reduction in homocysteine concentrations normalizing endothelial dysfunction coefficient parameters maximum left vent...

Methionine is an amino acid that extremely important for human health. To better understand the biochemical events occurring in body, excess molar properties of methionine and aqueous ethanol methanol mixtures were determined at 298.15 K. Interactions between components solutions are explained. Negative deviations from ideal state have been observed due to hydrogen bonds, dipole interactions, c...

Introduction: Feathers are important body structures that act as surface insulators to reduce maintenance energy requirements and also to protect skin against abrasions and infection. The purpose of this study is to investigate the effects of methionine injection into the yolk sac on development of feather follicle in chicken embryo. Methods: 50 fertilized eggs (weighting 50±0.4 gr) of Ross×...

Methionine has an almost unique stimulatory effect on biosynthesis of cephalosporins (by Cephalosporium acremonium). No other sulfur-containing compound tested, except dl-methionine-dl-sulfoxide, replaced methionine. dl-Methionine stimulated the synthesis of cephalosporins when added after the growth phase. The utilization of inorganic sulfate was repressed by methionine. Experiments with l-met...

Methionine metabolism forms homocysteine via transmethylation. Homocysteine is either 1) condensed to form cystathionine, which is cleaved to form cysteine, or 2) remethylated back to methionine. Measuring this cycle with the use of isotopically labeled methionine tracers is problematic, because the tracer is infused into and measured from blood, whereas methionine metabolism occurs inside cell...

The myeloperoxidase (MPO)-mediated decarboxylation of amino acids and the MPO-mediated oxidation of methionine, two potential bactericidal mechanisms, were compared. In the presence of the MPO system (MPO, 50 mU/ml; H(2)O(2), 0.1 mM; Cl(-), 75 mM), 50% of alanine (0.1 mM) was decarboxylated, whereas only 5% of methionine (0.1 mM) was decarboxylated. In contrast, under similar conditions, 80% of...