利用基因组重排技术选育高产洛伐他汀红曲菌株
Breeding of Monascus strains with high yield lovastatin by genome shuffling

采用基因组重排法选育高产洛伐他汀红曲菌株. 原生质体制备条件： 溶壁酶1.0%（质量分数），菌丝菌龄66h，酶解时间3h，酶解温度30℃，高渗磷酸盐缓冲液pH值为6.0，再生培养基的渗透压稳定剂为0.6mol·L-1 NaCl；原生质体灭活条件： 紫外灭活120s，微波灭活300s；原生质体融合条件： PEG 30%（质量分数），Ca2+ 0.03mol·L-1，30℃融合12min，原生质体融合率1.95%. 以经紫外和微波诱变得到的正突变菌株为亲本进行三轮基因组重排，获得一株遗传稳定、 高产洛伐他汀菌株R″-30，洛伐他汀产量较原始菌株SH2-7提高52%.
Genome shuffling was used to breed Monascus strains with high yield lovastatin. The results showed that the optimum conditions of Monascus protoplast preparation were as follows：lywallzyme concentration 1.0%，mycelium age 66h，enzymolysis time 3h and temperature 30℃， hypertonic phosphate buffer pH6.0，regeneration medium containing 0.6mol·L-1 NaCl. The protoplast inactivation conditions：UV treating 120s and microwave radiating 300s. The protoplast fusion rate could reach 1.95% after fusing in 30% PEG containing 0.03mol·L-1 Ca2+ for 12min at 30℃. A genetic stable fusant R″-30 was obtained after three rounds of genome shuffling，of which lovastatin yield was 52% higher than that of original strain SH2-7