天然无抗菌活性链霉菌种间原生质体融合与活性重组体的分离  

PROTOPLAST FUSION BETWEEN NATIVE ANTIBIOTICNONPRODUCING STREPTOMYCES SPECIES AND ISOLATION OF ACTIVE RECOMBINANTS

作　　者：林荣团 杨毓芬[1] 李焕娄[1] 

机构地区：[1]中国医学科学院医药生物技术研究所

出　　处：《生物工程学报》1990年第2期134-139,共6页Chinese Journal of Biotechnology

摘　　要：天然无抗菌活性的变青链霉菌1326与链霉菌1254的营养缺陷型变株进行种间原生质体融合,获得了原养型融合体,频率为10^(-6)—10^(-5)。融合前双亲株原生质体经52℃水浴处理4min,融合频率有所提高,约有一半的融合体菌株在琼脂平板上培养后显示有不同程变的抗菌活性,但绝大多数皆不稳定。从755株融合体中筛选到5株抗菌活性较稳定的菌株,并对其中三株所产生的抗生素作了初步鉴别。发现一株产生中性脂溶性抗生素,其余两株所产生的抗生素皆为碱性非典型脂溶性物质。尽管此等产物的理化性质还有待进一步鉴别,从中发现新化合物的几率是否大于传统的筛选途径,也还需要更多的筛选实践才能说明,但为了进一步开发利用微生物资源,这一途径似值得探讨。Neither Streptomyces lividans 1326 nor Streptomyces sp. 1254 produces any antimicrobiol antibiotics naturally. Protoplast fusion was performed between these species, and the interspecific fusants arose at frequencies of 10^(-6)—10^(-5). Heat treatment of both parental protoplasts at 52℃ for 4 minutes prior to fusion enhanced the fusion frequency to 4—32 times. About 50% of the fusants were genetically unstable, giving the segregants of parent and recombinant types. When the fusants were cultivated on agar plate, about half of them were active against Bacillus subtilis, but the antimicrobial activity was unstable. From 775 fusants, only 5 stable antibiotic-producing recombinants were obtained. Preliminary identification of antibiotics synthesized by three of the recombinants showed that recombinant F_(15) produced fat soluble neutral antibiotic. However, the antibiotics produced by F_(79) and F_(301) were fat soluble basic substances. These observations suggest that interspecific protoplast fusion might activate some silent genes of native antibiotic-nonproducing streptomyces, causing the recombinants to produce antibiotics. Though the products remain to be identified further, this strategy seems to be worth exploring for screening of new antibiotics.

关 键 词：链霉菌 抗生素 原生质体融合 发酵 

分 类 号：TQ927[轻工技术与工程—发酵工程]