脂质体介导的染色体和质粒DNA对链霉菌的转化

Liposome Mediated Transformation of Streptomyces Chromosomal and Plasmid DNA

一般认为放线菌细胞不易呈现感受态,而且分泌较多的细胞外核酸酶,致使放线菌的转化不易成功。虽然典型的转化存在于普通高温放线菌中,但已认为它们在进化上和大多数其他放线菌类群不同,缺乏代表性。因之,迄今以染色体DNA进行放线菌细胞转化的报道不多。

This paper reports that L-α-phosphatidylcholine and stearylamine(ratio 20: 1 (wt/wt) )as lipid film encapsulated S. lividans plasmid pIJ303and S. gingfengmyceticus chromosomal total DNA respectively andtransformed S. lividans 1326 and S. qingfengmyceticus A544 protoplastsin the presence of 50% PEG1000. Transformation frequencies increased35.91--207 times and 8.7--18.4 times higher than that of conventionaltransformation for liposomet-pIJ303 DNA and liposome-chromosmal DNArespectively, besides, liposome encapsulation can protect DNA from thenuclease degradation.There is no significant effect of different liposomesurface charge on transformation of S. lividans 1326 protoplast.