• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of bacteriology >Molecular cloning of tetracycline resistance genes from Streptomyces rimosus in Streptomyces griseus and characterization of the cloned genes.
【24h】

Molecular cloning of tetracycline resistance genes from Streptomyces rimosus in Streptomyces griseus and characterization of the cloned genes.

机译：灰链霉菌中来自线状链霉菌的四环素抗性基因的分子克隆和克隆基因的表征。

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Two tetracycline resistance genes of Streptomyces rimosus, an oxytetracycline producer, were cloned in Streptomyces griseus by using pOA15 as a vector plasmid. Expression of the cloned genes, designated as tetA and tetB was inducible in S. griseus as well as in the donor strain. The tetracycline resistance directed by tetA and tetB was characterized by examining the uptake of tetracycline and in vitro polyphenylalanine synthesis by the sensitive host and transformants with the resultant hybrid plasmids. Polyphenylalanine synthesis with crude ribosomes and the S150 fraction from S. griseus carrying the tetA plasmid was resistant to tetracycline, and, by a cross-test of ribosomes and S150 fraction coming from both the sensitive host and the resistant transformant, the resistance directed by tetA was revealed to reside mainly in crude ribosomes and slightly in the S150 fraction. However, the resistance in the crude ribosomes disappeared when they were washed with 1 M ammonium chloride. These results suggest that tetA specified the tetracycline resistance of the machinery for protein synthesis not through ribosomal subunits, but via an unidentified cytoplasmic factor. In contrast, S. griseus carrying the tetB plasmid accumulated less intracellular tetracycline than did the host, and the protein synthesis by reconstituting the ribosomes and S150 fraction was sensitive to the drug. Therefore, it is conceivable that tetB coded a tetracycline resistance determinant responsible for the reduced accumulation of tetracycline.
机译：通过使用pOA15作为载体质粒，在灰链霉菌中克隆了金霉素链霉菌生产者rimosus rimosus的两个四环素抗性基因。克隆基因的命名为tetA和tetB的表达可在灰链霉菌和供体菌株中诱导。由tetA和tetB指导的四环素抗性的特征在于，通过敏感的宿主和转化子以及生成的杂合质粒，研究四环素的摄取和体外聚苯丙氨酸的合成。用粗核糖体和携带tetA质粒的灰链霉菌的S150组分合成的聚苯丙氨酸对四环素具有抗性，并且通过来自敏感宿主和抗性转化体的核糖体和S150组分的交叉测试，tetA指导的抗性被发现主要存在于粗核糖体中，略微存在于S150中。然而，当用1M氯化铵洗涤时，粗核糖体的抗性消失了。这些结果表明，tetA并非通过核糖体亚基而是通过未知的细胞质因子指定了蛋白质合成机制的四环素抗性。相反，携带tetB质粒的灰链霉菌比宿主积累更少的细胞内四环素，并且通过重组核糖体和S150组分的蛋白质合成对药物敏感。因此，可以想象tetB编码导致减少四环素积累的四环素抗性决定簇。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号