Density functional theory methods(DFT) and natural bond orbital (NBO) analysis were used to investigate the effects of isomerism and side chain mutation at a microscopic level on the stability, binding energy and NMR/NQR tensors of structural isomers, L- methionylasparagine (Met-Asn) and L- asparagylmethionine (Asn-Met) in the gas phase. The results represented that the isomerism and side chain...

Amino acid dehydrogenases (L-amino acid: oxidoreductase deaminating EC 1.4.1.X) are members of the wider superfamily of oxidoreductases that catalyze the reversible oxidative deamination of an amino acid to its keto acid and ammonia with the concomitant reduction of either NAD+, NADP+ or FAD. These enzymes have been received much attention as biocatalysts for use in biosensors or diagnostic kit...

Background: The search for potent radioprotective agents for the amelioration of radiation side effect is an important aim in radiobiology. The present study aimed to evaluate the effects of curcumin and seleno-L-methionine against radiation-induced micronucleus formation in rat bone marrow.Methods: In total, 40 male rats were divided into 8 groups (n=5 each), including control, curcumin or sel...

amino acid dehydrogenases (l-amino acid: oxidoreductase deaminating ec 1.4.1.x) are members of the wider superfamily of oxidoreductases that catalyze the reversible oxidative deamination of an amino acid to its keto acid and ammonia with the concomitant reduction of either nad+, nadp+ or fad. these enzymes have been received much attention as biocatalysts for use in biosensors or diagnostic kit...

Two separate studies were conducted using a continuous culture fermenter system to determine effects of supplementing D,L-methionine and various methionine derivatives on degradation of methionine by ruminal bacteria. A basal diet containing 20% alfalfa hay, 20% corn silage and 60% grain mix (DM basis) was provided at a rate of 75 g DM/d per fermenter and served as an unsupplemented control in ...

The nitrogen-sparing effect of methionine, methionine sulphoxide, homocystine, cystine and choline was studied in rats by determining dialy N excretions during 5 d after changing from a high-protein diet to a protein-free diet, L-glutamic acid was used as a negative control. 2. L-, D- and DL-methionine were equally active in sparing N. L-methionine sulphoxide, DL-homocystine and L-cystine were ...

The Panel noted that N-acetyl-L-methionine is deacetylated in animals and humans to Lmethionine. The bioavailability of methionine from N-acetyl-L-methionine is comparable to that from L-methionine used as such as similar mean plasma methionine concentrations were recorded in pigs and in humans after loading with equimolar quantities of each, as L-methionine and Nacetyl-L-methionine were equall...

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...

1. Double-reciprocal plots of the reaction velocity of yeast, rat liver and Escherichia coli ATP-l-methionine S-adenosyltransferases (EC 2.5.1.6) as a function of the l-methionine concentrations (under saturating ATP conditions) demonstrate downward deflexions from linearity for the yeast and E. coli adenosyltransferases and an upward deflexion for the rat liver enzyme. 2. The activities of par...