PURPOSE To evaluate the differences between fludeoxyglucose F 18 (FDG) and L-methyl-11C-methionine (11C-methionine) as tracers for positron emission tomography (PET) in the evaluation of brain tumors. METHODS We analyzed 10 patients with histologically verified cerebral glioma or meningioma and 1 patient with a neuroradiologic diagnosis of low-grade glioma by using FDG, 11C-methionine, and PE...

The [c-lactam] derivative of cobalamin antagonizes vitamin B12 in vivo. Therefore, we investigated its effects in tissue culture to develop a model in which to study vitamin B12-deficient hemopoiesis. HL60 cells were cultured in medium containing either methionine or L-homocysteine thiolactone, and various concentrations of 5-methyltetrahydrofolate or pteroylglutamic acid. In medium with L-homo...

Methylthioadenosine phosphorylase (MTAP), an enzyme involved in purine and methionine metabolism, is present in all normal tissues but is frequently deficient in a variety of cancers. It has been suggested that this metabolic difference between normal and cancer cells may be exploited to selectively treat MTAP-negative cancers by inhibiting de novo purine synthesis and by depleting L-methionine...

BACKGROUND Moderate elevations in plasma homocyst(e)ine concentrations are associated with atherosclerosis and hypertension. We tested the hypothesis that experimental perturbation of homocysteine levels produces resistance and conduit vessel endothelial dysfunction and that this occurs through increased oxidant stress. METHODS AND RESULTS Oral administration of L-methionine (100 mg/kg) was u...

L-Methionine gamma-lyase (MGL) catalyzes the pyridoxal 5'-phosphate (PLP) dependent alpha,gamma-elimination of L-methionine. We have determined two crystal structures of MGL from Pseudomonas putida using MAD (multiwavelength anomalous diffraction) and molecular replacement methods. The structures have been refined to an R-factor of 21.1% at 2.0 and 1.7 A resolution using synchrotron radiation d...

A new assay for measuring protein-methionine-S-oxide reductase is reported. The assay measures the conversion of N-(9-fluorenylmethoxycarbonyl)-methionine sulfoxide to N-(9-fluorenylmethoxycarbonyl)-methionine using fluorescence detection after high-performance liquid chromatography separation. Enzyme activity is linear over a 60-min period and the assay is sensitive enough to detect the consum...

dl-Methoxinine and dl-ethionine prevent the propagation of influenza PR8 virus in a medium ordinarily favorable. The inhibitors do not act by destroying the virus, the host tissue, or by preventing the infection of the cells, but by interfering with the synthesis of the virus. The action of the inhibitors can be blocked by l-methionine. l-Methionine is involved in the biosynthesis of influenza ...

OF THESIS Submitted in partial fulfillment of the requirements for the degree of Master of Science in Chemistry in the Graduate School of Northeastern University April 2012

Effects of sodium selenite (SS) in offspring of broiler breeders has been reported, but the comparison between SS and different level of methionine on offspring has received limited, so this study was conducted to investigate sodium selenite and methionine effects on concentration of selenium in egg and serum of Iranian native broiler breeders. An experiment was conducted in 3 × 3 factorial exp...

The enzyme BchM (S-adenosyl-L-methionine:magnesium-protoporphyrin IX O-methyltransferase) from Rhodobacter capsulatus catalyses an intermediate reaction in the bacteriochlorophyll biosynthetic pathway. Overexpression of His(6)-tagged protein in Escherichia coli resulted in the majority of polypeptide existing as inclusion bodies. Purification from inclusion bodies was performed using metal-affi...