The superiority of d-methionine over l-methionine for stimulation of cephalosporin C synthesis in a crude medium was confirmed. The optimal level of dl-methionine was 0.5%. Methionine stimulates growth slightly but this is not thought to be the cause of the marked stimulation of antibiotic synthesis. Of a large number of sulfur compounds tested, only dl-methionine-dl-sulfoxide and S-methyl-l-cy...

1. L-[U-14C]methionine was used to study methionine metabolism in sheep fed on untreated silage, silage treated with formaldehyde and untreated silage plus intraperitoneal infusion of L-methionine. 2. Over-all the values ranged from 0.43 to 0.86 mmol/h for methionine turnover rate, from 13.3 to 19.9 for the percentage of methionine oxidized to carbon dioxide and from 245 to 1089 mumol for methi...

The conversion of methionine to cyst(e)ine was determined in sheep infused with different amounts of methionine (0-5 g/d) into the duodenum by assaying the incorporation of 35S from intravenously-infused L-[35S]methionine into cyst(e)ine in wool, plasma albumin and the free plasma pool. The percentage of cystine-S in the plasma originating from methionine increased linearly from 4.5 to 18 with ...

Plasma amino acid response of wethers to abomasal infusions of DL-methionine (DLM), DL-homocysteine thiolactone-HCl (HCTL) and N-acetyl-DL-methionine (NAM), in vivo rumen stability of the latter two methionine analogs and preintestinal absorption of HCTL were studied. The daily infusion of 1.06 g of DLM elevated molar percentage of methionine and lysine in plasma'and decreased molar percentage ...

Methionine is often the first limiting amino acid for growing cattle. This study was conducted to determine how methionine metabolism is regulated in the liver of growing steers. Six ruminally cannulated steers were used in a replicated 3 × 3 Latin square experiment. Either 0, 5, or 10 g/day L-methionine was infused into the abomasum. These treatments were designed to be deficient, adequate, an...

Methionine residues in proteins react readily with reactive oxygen species making them particularly sensitive to oxidation. However, because oxidized methionine can be reduced back in a catalyzed reaction, it has been suggested that methionine residues act as oxidant scavengers, protecting not only the proteins where they are located but also the surrounding macromolecules. To investigate wheth...

Human beings are only capable of synthesizing ten of twenty naturally occurring amino acids. The other essential amino acids are obtained from the diet. Cereal grains are often limiting for lysine, tryptophan and threonine, while the legume seeds have an adequate level of lysine but are limiting for the sulphurcontaining amino acids, methionine and cysteine. Animals can convert methionine into ...