Isolation And Identification Of L-Serine Prdoucer Strain MB200 And Its Serine Hydroxymethyltransferase Gene

L-Serine is used as a component of amino acids infusion, an additive of cosmetics, and as a starting material for the enzymatic production of tryptophan. The L-serine production of methylotrophs is the highest so far reported for microbes, methanol and glycine used in production are inexpensive, so we can obtain more profit.A strain that can grow with methanol as the sole source of carbon, MB200, was isolated from the soil samples at a digester of Longan GuangXi. On the basis of observing of modality and the analysis of the 16S rDNA sequence, MB200 was identified as Methylobacterium extorquens primarily. The optimum culture conditions for the strain were: temperature32℃, pH7.0, methanol concentration 1.25%. After optimizing the resting cells culture conditions, the optimum conditions were obtained: glycine 10mg/ml, methanol 50 mg/ml, cell density 30 mg/ml, pH8.9, temperature32℃, resting cells incubation time 48 h, under...