小麦白粉病生防菌G-1菌株原生质体诱变育种

Protoplast mutagenesis breeding of Streptomyces sp.G-1 against Blumeria graminis

以链霉菌G-1(Streptomyces sp.G-1)为出发菌株,通过研究菌株G-1原生质体形成与再生的条件,发现该菌株在含0.5%甘氨酸的菌丝体培养基中经过二次培养后,所得菌丝体用2 mg/mL溶菌酶在30℃下处理90 min,可获得大量原生质体,其再生率可达8.2%。菌株G-1的原生质体经紫外诱变和宁南霉素抗性筛选后,得到一高产突变株G-1-125,其有效组分A的产量达到794mg/L,较出发菌株提高了180%。

In order to screen a high-yielding strain of Streptomyces sp. G-1, factors affecting protoplasts preparation and regeneration were investigated. Results showed that the mycelia eutured in a hypha medium containing 0.5 % glyeine were processed with 2 mg/mL lysozyme at 30 ℃. for 90 minutes, the regeneration frequency of protoplasts could reach up to 8.2 %. Then the protoplasts were mutated by UV radiation and spread on regeneration plates containing 4 mg/mL ningnanmycin. After incubation and selection, a mutant G-1-125 was obtained . Its yield was as high as 794 mg/L, increased by 180% compared with that of the starting strain.