【摘要】 从黄色短杆菌Brevibacterium flavumATCC-21269出发选育DL-丙氨酸产生菌。以硫酸二乙酯（DES）诱变处理,从中得到一株SSZM₂菌,能在培养基中积累少量丙氨酸。通过连续诱变及单菌落分离,选育得到一株产丙氨酸较高的突变株SSZM₉。试验表明生物素是积累DL-丙氨酸的促进因子,在其他发酵条件的配合下,该菌可在发酵液里积累4.5％的DL-丙氨酸,对糖转化率为38％。更多还原

【Abstract】 A DL-alanine producing mutant SSZM₉ derived from Brevibacteriu flavum ATCC 21269 was obtained by means of mutation with diethyl sulphate（DES） and ultraviolet light（U V） and single colony isolation. It was found that biotin was a paomotive factor for its DL-alanine accumulation. In shaker more than 45mg/ml DL-alanine was accumulated in a medium containing 12% glucose. 3.5%（NH₄）₂SO₄. 0.15% KH₂PO₄. 0.05% MgSO₄. 7H₂O. 0.05% urea, 50ug/L biotin. 1mg/1 thiamine, 20ml/L Soybean protein hydrolyzate and 4% CaCO₃, pH7.6 under the condition of shaker 240 r. p. m at 30℃ for 72h.更多还原