The objectives of this study were to evaluate ruminal degradation and intestinal digestion of two ruminally protected methionine (RPM) products and to assess the potential use of changes in plasma methionine concentrations as an indication of methionine availability to the animal. Ruminal degradation of the protected methionine was assessed using the in situ technique. The intestinal availabili...

PURPOSE Many neoplasms are vulnerable to methionine deficiency by mechanisms that are poorly understood. Because gene profiling studies have revealed that methionine depletion increases TNF-related apoptosis-inducing ligand receptor-2 (TRAIL-R2) mRNA, we postulated that methionine stress sensitizes breast cancer cells to proapoptotic TRAIL-R2 agonists. EXPERIMENTAL DESIGN Human triple (ER/PR/...

Methionine has been shown to increase plasma cholesterol in animals. In the present study, mechanisms were investigated by which methionine could alter cholesterol metabolism. In the first experiment, forty growing rats were fed four casein-based diets differing in methionine content (2.6, 3.5, 4.5 or 6.0 g/kg) for 14 d. In the second experiment, isolated rat hepatocytes were incubated in media...

The Bacillus subtilis yusCBA operon, which encodes an ABC-type transporter, contains an S-box motif in its promoter region. We showed that the expression of these genes is repressed via the S-box system when methionine is available. The YusCB proteins are involved in the transport of both d- and l-methionine but also methionine sulfoxide. A yusCB mutant is unable to grow in the presence of 5 mi...

The death of a control subject after an oral load of methionine for a study of the possible relationship between homocysteine and Alzheimer’s disease is reported. The subject developed postload plasma concentrations of methionine far beyond those reported previously in humans given the usual oral loading dose of methionine (100 mg/kg body wt). Her preload plasma metabolite values rule out known...

Six ethionine-resistant (Etr) regulatory mutants of Saccharomycopsis lipolytica Sl/1 overproducing methionine have been isolated. Five of them are also resistant to seleno-methionine. The activity of homocysteine synthase (O-acetyl-L-hormoserine-acetate lyase, adding hydrogen sulfide) is derepressed in these mutants and is not susceptible to the methionine-mediated repression. The pool of free ...

Methionine residues in alpha/beta-type small, acid-soluble spore proteins (SASP) of Bacillus species were readily oxidized to methionine sulfoxide in vitro by t-butyl hydroperoxide (tBHP) or hydrogen peroxide (H2O2). These oxidized alpha/beta-type SASP no longer bound to DNA effectively, but DNA binding protected alpha/beta-type SASP against methionine oxidation by peroxides in vitro. Incubatio...