No abstract available.
Methionine*

The levels of ergothioneine (ERG), which have been shown to act as an excellent antioxidant, were determined in both fruiting bodies and mycelia of various mushroom species. We found that ERG accumulated at different levels in fruiting bodies of mushrooms and showed up to a 92.3-fold difference between mushrooms. We also found that ERG accumulated at higher levels in mycelia than in fruiting bodies of economically important mushroom species such as Ganoderma neo-japonicum, G. applanatum and Paecilomyces tenuipes. The addition of 2 mM methionine (Met) to mycelial culture medium increased the ERG contents in most mushroom species tested, indicating that Met is a good additive to enhance the ERG levels in a variety of mushroom species. Taking these results into consideration, we suggest that the addition of Met to the mycelial culture medium is an efficient way to enhance the antioxidant properties in economically important mushroom species.
Agaricales ; Ergothioneine ; Fruit ; Ganoderma ; Methionine ; Paecilomyces

OBJECTIVES: To predict the structure of protein, which dictates the function it performs, a newly designed algorithm is developed which blends the concept of self-organization and the genetic algorithm. METHODS: Among many other approaches, genetic algorithm is found to be a promising cooperative computational method to solve protein structure prediction in a reasonable time. To automate the right choice of parameter values the influence of self-organization is adopted to design a new genetic operator to optimize the process of prediction. Torsion angles, the local structural parameters which define the backbone of protein are considered to encode the chromosome that enhances the quality of the confirmation. Newly designed self-configured genetic operators are used to develop self-organizing genetic algorithm to facilitate the accurate structure prediction. RESULTS: Peptides are used to gauge the validity of the proposed algorithm. As a result, the structure predicted shows clear improvements in the root mean square deviation on overlapping the native indicates the overall performance of the algorithm. In addition, the Ramachandran plot results implies that the conformations of phi-psi angles in the predicted structure are better as compared to native and also free from steric hindrances. CONCLUSIONS: The proposed algorithm is promising which contributes to the prediction of a native-like structure by eliminating the time constraint and effort demand. In addition, the energy of the predicted structure is minimized to a greater extent, which proves the stability of protein.
Enkephalin, Methionine ; Islet Amyloid Polypeptide ; Operator Regions, Genetic ; Peptides

OBJECTIVE: This study concernes the usefulness of 11C-methyl-L-and D-methionine(Met)-positron emission tomography(PET) for gliomagrading and detection of recurrence in gliomas, compared with fluorine-18, 2-fluoro-deoxyglucose(FDG)-PET. METHODS: Eighty patients underwent Met-PET study for evaluation of glioma: 37 astrocytomas (WHO grade II, 3; III, 8; IV, 26), 27 oligodendrogliomas (WHO grade II, 16; III, 11), and 12 suspicious recurrent gliomas. All images were taken within 2 weeks before operation. For suspicious recurrent cases on magnetic resonance images, both FDG-PET and Met-PET were performed. RESULTS: In astrocytoma, Mean maximum standard uptake value(SUV) of region of interest(ROI) was not different between WHO grades (p=0.108), but ROI/normal contralateral tissue SUV (T/N) ratio was statistically different between WHO grades (p=0.002). T/N ratio was more closely related to visual scale than maximum SUV of ROI (p<0.001 and p=0.107 respectively). In oligodendroglioma, there was no statistical difference between WHO grades in view of maximum SUV and T/N ratio. For recurrent gliomas, sensitivity of FDG-PET and Met-PET was 25% and 100%, while specificity of FDG-PET and Met-PET were 100% and 80%, respectively. CONCLUSION: Met-PET might be an appropriate tool for tumor grading in astrocytom a and be more sensitive for detection of recurrence in gliomas than FDG-PET.
Astrocytoma ; Glioma* ; Humans ; Methionine ; Neoplasm Grading ; Oligodendroglioma ; Recurrence* ; Sensitivity and Specificity

This research is to examine the detoxication effect of methionine on cadmium intoxication. For this purpose, this paper provides an analysis of the data on the groups of mice (ICR), one group of mice treated with 40 ppm of cadmium only, and other groups of mice combined-treated with cadmium and 0.1%, 0.25%, 0.5% and 1% methionine. After breeding for 40 days, the data on the growth of mice, changes in activation of alkaline phosphatase in blood, and the cadmium content in the liver and kidney, are analysed. The results were as follow: 1) The growth-rate of mice, in the cadmium only injected group, was declined by 9% in comparison with the control group after 40 days. But the two groups of cadmium with 0.5% and 1% methionine showed the rise of 9% and 14% respectively above the growth-rate of the control group. The results from the groups of cadmium with 0.1% and 0.25% methionine were similar to that from the cadmium only injected group. 2) Changes in activation of alkaline phosphatase in blood decreased to 86.45% in the cadmium only injected group behind the 100% activation of the control group. The groups of cadmium with 0.1% and 0.25% methionine showed no difference with the former group. But the groups of cadmium with 0.5% and 1% methionine recovered to the 93.14% and 96.08% of activation respectively. 3) The mean content of cadmium in the liver was 0.028+/-0.001 microgram/g in the control group. The cadmium only injected group showed the mean cadmium content of 2.80+/-0.62 microgram/g in the liver, which was similar to 2.82+/-1.03 microgram/g in the group of cadmium with 0.1% methionine, and 2.56+/-0.77 microgram/g in the group of cadmium with 0.25% methionine. But the groups of cadmium with 0.5% and 1% methionine showed the reduction of cadmium contents in the liver to 1.84+/-0.56 microgram/g and 1.74+/-0.35 microgram/g respectively. In the kidney, the groups of cadmium with 0.1%, 0.25% and 0.5% methionine showed the similar cadmium content to the group treated with cadmium only. But the group of cadmium with 1% methionine showed a small increase to 4.13+/-1.00 microgram/g in comparison with the group treated with cadmium only. This analysis proves that the mobility and diffusion of cadmium in the tissues advance faster in the group treated with cadmium and methionine than in the group treated with cadmium only.
Alkaline Phosphatase* ; Animals ; Breeding ; Cadmium* ; Diffusion ; Kidney* ; Liver* ; Methionine* ; Mice*

Methylation plays a vital role in biological systems. SAM (S-adenosyl-L-methionine), an abundant cofactor in life, acts as a methyl donor in most biological methylation reactions. SAM-dependent methyltransferases (MTase) transfer a methyl group from SAM to substrates, thereby altering their physicochemical properties or biological activities. In recent years, many SAM analogues with alternative methyl substituents have been synthesized and applied to methyltransferases that specifically transfer different groups to the substrates. These include functional groups for labeling experiments and novel alkyl modifications. This review summarizes the recent progress in the synthesis and application of SAM methyl analogues and prospects for future research directions in this field.
S-Adenosylmethionine/metabolism* ; Methionine ; Methyltransferases/metabolism* ; Methylation ; Racemethionine

PURPOSE: The neonatal screening test for homocystinuria primarily measures methionine by using a dried blood specimen. We investigated the incidence and clinical manifestations of homocystinuria, isolated hypermethioninemia, and transient hypermethioninemia among patients with hypermethioninemia on a neonatal screening test. METHODS: We performed a retrospective study of 58 patients transferred to Shoonchunhyang Hospital because of hypermethioninemia on a neonatal screening test between January 1996 and August 2009. We analyzed the level of amino acid from plasma and urine, as well as blood homocysteine. RESULTS: Almost half of the 58 patients were identified as normal. Whereas only 3 (5.1%) patients were identified as having homocystinuria, about 20.7% (12 cases) of the patients had isolated hypermethioninemia. The ages of these two groups at initial detection of hypermethioninemia on plasma amino acid analysis were 50.0+/-22.5 days and 34.9+/-13.5 days, respectively. Both groups were put on diets, and they showed a normal developmental course as a result of early diagnosis and treatment. CONCLUSION: Hypermethioninemia without homocystinuria, referred to as isolated hypermethioninemia, was also detected. Thus, the impact of hypermethioninemia on a neonatal screening test should be carefully evaluated through analysis of amino acid levels from blood and urine, and we need to detect and treat an early stage of isolated hypermethioninemia as well as homocystinuria.
Diet ; Early Diagnosis ; Homocysteine ; Homocystinuria ; Humans ; Incidence ; Infant, Newborn ; Methionine ; Neonatal Screening ; Plasma ; Retrospective Studies

To utilize Pichia pastoris to produce S-adenosyl-L-methionine (SAM), an intracellular expression vector harboring S. cerevisiae SAM2 was transformed into GS115. A recombinant strain having 2 copies of expression cassette was obtained through G418 resistance screening. This strain had higher SAM synthetase activity and higher SAM production capacity than the original strain, when cultured in medium containing methanol and methionine. The carbon source and nitrogen source of medium was optimized. The results showed SAM production by this strain was closely related to carbon metabolism. With supplementation of 0.2% glycerol every day from the beginning of 3rd day, this strain produced 1.58 g/L SAM when cultured in a medium containing 0.75% L-methionine and optimized carbon and nitrogen source after 6 days.
Methionine Adenosyltransferase ; genetics ; metabolism ; Pichia ; genetics ; Recombinant Proteins ; metabolism ; S-Adenosylmethionine ; biosynthesis

The yield of S-adenosyl-L-methionine (SAM) on high-cell-density fermentation by saccharomyces cerevisiae is mostly affected by the feeding strategy of pre-L-methionine. The mutant strain SAM0801 that could accumulate more SAM was used in this study. Six high-cell-density fermentation experiments in 5 L fermentor were investigated to get the optimal feeding time and amount of L-methionine. The results showed that when 40 g L-methionine was added in the fermentor after 30 h fermentation, a dry cell weight of 100 g/L was achieved. Under this condition, after 58 h fermentation, both the dry cell weight and the yield of SAM reached the maximum, 168 g/L and 14.48 g/L respectively.
Bioreactors ; microbiology ; Fermentation ; Methionine ; analysis ; metabolism ; Mutation ; S-Adenosylmethionine ; biosynthesis ; Saccharomyces cerevisiae ; genetics ; growth & development ; metabolism

The neonatal screening test for homocystinuria has mostly measured methionine by use of dried blood specimen. Isolated hypermethioninemia, clinically benign metabolic disorder associated with the deficiency of methionine adenosyl transferase in liver, is discovered in neonatal mass screening tests for homocystinuria. We diagnosed two cases of isolated hypermethioninemia using the amino acid analysis and the liver function tests for newborns with increased methionine level in the Guthrie screening test for homocystinuria. For the first time in Korea, we report two cases of patients with isolated hypermethioninemia with a brief review of literatures.
Homocystinuria ; Humans ; Infant, Newborn ; Korea ; Liver ; Liver Function Tests ; Mass Screening* ; Methionine ; Neonatal Screening ; Transferases