ARTP诱变选育高产海藻糖菌株及酶促反应条件优化
Breeding of the trehalose high-yielding strain by ARTP and the optimization of enzymatic reaction conditions
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摘要: 以实验室保藏的节杆菌属菌株Arthrobacter sp.SH为出发菌株,经常压室温等离子体(atmospheric and room temperature plasma,ARTP)诱变选育后,筛选到一株以淀粉为原料Tre Y-Tre Z途径生产海藻糖的高产突变菌株Arthrobacter sp.SH-52。该突变菌株酶催化能力达到129.6 U/m L,比出发菌株提高了46.1%。对菌株Arthrobacter sp.SH-52的酶促反应条件进行优化,结果表明,酶促反应最适温度45℃,最适反应时间30 h,最适初始p H 6.5,最适底物为浓度20%的淀粉液化液(DE值为11.9)。经酶促反应优化后,采用未经纯化的粗酶液进行催化,转化率达到37.6%。实验结果表明ARTP诱变是选育高酶活海藻糖生产菌的有效方法,研究结果对工业化生产海藻糖具有一定的借鉴价值。Abstract: A genetic stability trehalose high-yielding strain Arthrobacter sp. SH-52 was obtained from the original strain of Arthrobacter sp. SH, which was mutated by atmospheric and room temperature plasmas ( ARTP) . The catalysis ability of Arthrobacter sp.SH-52 reached 129.6 U/m L, which was 46.1% higher than that of the original strain. The enzymatic reaction conditions of SH-52 were optimized, and the results were as follows: reaction temperature 45 ℃, reaction time 30 h, p H6.5, and DE value 11.9 of 20% starch hydrolysate.Under the optimum reaction conditions, the conversion rate reached 37.6% by crude enzyme.The results showed that ARTP mutagenesis technology was an effective method for breeding high-activity trehaloseproducing bacteria, and the results could be used for industrial production of trehalose.