【摘要】 对洋葱伯克霍尔德氏菌L 68生长及产邻苯二酚2,3 双加氧酶(C23D)的条件进行了研究,其最适产酶pH7.2;最适生长温度30～35℃;最适培养时间48h;苯酚浓度0.09%最有利于菌体产酶.对菌株L 68产生的C23D酶进行了纯化,超声波破碎后的细胞提取液经硫酸铵分级沉淀、DEAESepharoseFastFlow层析、Hydroxyapatite层析、SephadexG 150层析后,收率为20%,酶比活力提高了230倍.SDS PAGE检测得到了分子量为(34±1)kDa的蛋白.更多还原

【Abstract】 Burkholderia cepacia L68 can secrete a phenoldegradation enzyme,catechol 2,3dioxygenase(C23D).The enzymeproduction conditions of the bacterium were studied.Strain L68 grew well at neutral pH and the pH optimum for C23D production was 7.2.The optimum temperature for its growth and enzyme production was 30～35 ℃.The specific activity of C23D was the highest when the strain was cultivated for 48 h.The best concentration of phenol was 0.09%.The enzyme was purified by ammonium sulfate precipitation,DEAE Sepharose ionexchange chromatography,Hydroxyapatite Adsorption chromatography,Sephadex G150 chromatography,the recovery rate was 20% and the enzyme activity function after purification was 230 times higher.A single band protein with molecular weight of (34±1) kDa was detected by SDSPAGE.更多还原