Intact chloroplasts, purified from spinach leaves by sedimentation in density gradients of colloidal silica, incorporate labeled amino acids into at least 16 different polypeptides of the thylakoid membranes, using light as the only source of energy. The thylakoid products of chloroplast translation were visualized by subjecting membranes purified from chloroplasts labeled with [35S]methionine ...

Hypoxanthine phosphoribosyltransferase (HPRT, IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8) can be purified 5-to 10,000-fold from extracts of HeLa (human) cells by a three-step procedure consisting of high-speed centrifugation, adsorption to Sepharose-conjugated HPRT antibody, and sodium dodecyl sulfate/polyacrylamide gel electrophoresis. Purified enzyme labeled in vivo with radioact...

background : increased level of serum homocysteine is one of the risk factor of atherosclerosis. its production related in some sulfur amino acids such as methionine. some important cofactors that are involved in metabolic pathways of this amino acid are folate and vitamin b12. we have assessed the status of methionine, folic acid, and vitamin b12 in some coronary atherosclerotic male patients....

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...

the current study intends to analyze the effects of methionine on the ovulation of guinea pigs. 60 guinea pigs were given 4 different treatments in a completely randomize design. the treatments contained 0, 2, 4 and 6 percent of methionine per kg as fed. after two weeks as adaptation period, the four different treatments were given to the animals for two estrus cycle. after synchronization whic...

a study was carried out to examine the effect of different levels of herbal methionine and dl-methionine on the growth performance and immunocompetence of broiler chickens fed on a corn-soybean meal diet. a total of 225 old male broiler chickens (ross 308) were used as experimental samples in a completely randomized design. they were randomly assigned to 9 treatments each of 5 replicates in eve...

a study was carried out to investigate the effects of organic acid mixture as well as two methionine supplements on performance, carcass characteristics and weight of gastrointestinal tract in broiler chickens. six hundred unsexed day-old ross 308 broiler chicks were utilized in a factorial arrangement of treatments (3×2) based on completely randomized design (crd) of 4 replicates of 25 chicks ...