Studies On Biotransformation Of S-Adenosyl-L-Methionine

The examine method of thin built-up, dividing light intensity with Ultraviolet ray and HPLC with the 0.02 mol/ L HCOONH₄ for fluid liquid mutually method were built up .In this experiment, the strains of Y1947, which could produce SAM, were guided to change by Ultraviolet ray and , getting the 1 stubs 62# to produce the higher germ stub of SAM, fermenting the liquid SAM yield to come to a the 1250 mg/L.In develop and convert process, the difference turns towards shaking and 5 L bottle for ferment to carry on excellently. In the optimization of culture conditions, the initial broth pH , fermentation temperature and the concentration of L-methionine in the broth were examined.The optimized conditions were pH 5.5, temperature 30℃ and substrate concentration 0.5%. In the optimization of media, the C source, N source and mineral ion were studied.The optimal C source was 5% sucrose, N source 0.7% NH₄ NO₃, P source 0.4% KH₂PO₄ and KH₂PO₄ 0.2% and mineral ion 0.01%MgSO₄ ·7H₂O 0.2 and MgSO₄·7H₂O 0.2 and MnSO₄·7H₂O 0.01g/L and Sulfuric acid adenine 0.01and ZnCl₂ 0.01.While studying the conversion of SAM, the dynamics model that was builded up to synthesize the SAM and was carried on the study.The yeast cell disruptions were researched with abrasives, ultrasonic, toluene H₂SO₄. The results of disruption was the best with H2SO4. The operation conditions were 0.35 mol/L H₂SO₄.Discussed the dynamics factor of the accumulating SAM inside yeast, demonstrated the energy metabolism was important in biotransformantion of SAM, adopted the metabolism overfall to discribe the growth and the synthesis of the aerobic germ, could compare goodly be illuminated.Exploited the new craft to separate the SAM by the reinecke salt, making the recovery rate of the sulfate of SAM above 60% and the recovery rate of p-toluenesulfonic acid salt above 50%.Adopting the ion exchange resin to separate SAM and proved that the method had the advantages of the simple craft and the high recovery rate etc.