The transport of l-methionine by the gram-positive species Brevibacterium linens CNRZ 918 is described. The one transport system (K(m) = 55 muM) found is constitutive for l-methionine, stereospecific, and pH and temperature dependent. Entry of l-methionine into cells is controlled by the internal methionine pool. Competition studies indicate that l-methionine and alpha-aminobutyric acid share a...

D-methionine was administered intraperitoneally to rats in tracer (22.5 pmoles/kg) and large doses (4.7 mmoles/kg) and the brain levels of total (D + L) methionine, as well as of cysteine (+cystine) and glutathione were determined. The effect of co-administering the convulsant agent, L-methionine-DL-sulfoximine (MSO) was also examined. The administration of tracer doses of Cl2-D-methionine resu...

An experiment was conducted to evaluate the effect lysine and methionine supplementation low protein diet on production performance serum biochemical parameters in Vanaraja laying hens. One hundred twenty (n=120), 30-weeks old hens were randomly distributed into four dietary treatments with three replicates each group having 10 birds replicate. Four diets formulated 2600 kcal/kg of metabolizabl...

A 2×5 factorial experiment, using 2 dietary methionine levels (0.28% and 0.48%) and 5 dietary choline levels (0, 394, 823, 1,239, and 1,743 mg/kg), was conducted to study the effects of dietary methionine status on choline requirements of starter white Pekin ducks from 7 to 28 days of age. Four hundred eighty 7-d-old male White Pekin ducks were randomly allotted to ten dietary treatments, each ...

To determine the rates of methionine splanchnic uptake and utilization in critically ill pediatric patients we used two kinetic models: the plasma methionine enrichment and the "intracellular" homocysteine enrichment. Twenty four patients, eight infants, eight children, and eight adolescents, were studied. They received simultaneous, primed, constant, intravenous infusions of l-[(2)H(3)]methylm...

Salmonella typhimurium possesses a permease specific for L-methionine (K, of 0.1 to 0-2 p ~ ) . Competition studies have shown that the permease has little or no affinity for the other L-amino acids commonly found in proteins. Methionine uptake was competitively inhibited by the growth inhj bitory analogues DLethionine, a-methyl-DL-methionine and DL-methionhe-DL-sulphoximine. Mutants resistant ...

It has been indicated lately that higher plasma homocysteine is one of the risk factors in neural tube defects(NTDs) and vascular disease. Methionine synthase is a key enzyme in homocysteine metabolism. The defects of methionine synthase activity could result in hyperhomocysteinemia and methionine auxotrophy. The gene mutations of methionine synthase with the epidemiological studies of NTDs are...

1. Glycylsarcosine, a peptide which is slowly hydrolysed by the intestine, is transported into the jejunal mucosal cells of the hamster by an active Na+-dependent process. 2. Uptake of glycylsarcosine is inhibited by L-methionyl-L-methionine but not by L-methionine, suggesting that L-methionyl-L-methionine and glycylsarcosine share an uptake mechanism which is independent of that for free methi...