Natural transformation of Thermotoga sp. strain RQ7

BMC Biotechnology

Dongmei Han¹  Hui Xu¹  Rutika Puranik¹  Zhaohui Xu¹ 

[1] Department of Biological Sciences, Bowling Green State University, 43403 Bowling Green, OH, USA

关键词: pDH12;    pDH10;    Natural competence;    Natural transformation;    Thermotoga;   

Others  :  834854
DOI  :  10.1186/1472-6750-14-39

 received in 2013-11-06, accepted in 2014-05-02,  发布年份 2014

【 摘 要 】

Background

Thermotoga species are organisms of enormous interest from a biotechnological as well as evolutionary point of view. Genetic modifications of Thermotoga spp. are often desired in order to fully release their multifarious potentials. Effective transformation of recombinant DNA into these bacteria constitutes a critical step of such efforts. This study aims to establish natural competency in Thermotoga spp. and to provide a convenient method to transform these organisms.

Results

Foreign DNA was found to be relatively stable in the supernatant of a Thermotoga culture for up to 6 hours. Adding donor DNA to T. sp. strain RQ7 at its early exponential growth phase (OD₆₀₀ 0.18 ~ 0.20) resulted in direct acquisition of the DNA by the cells. Both T. neapolitana chromosomal DNA and Thermotoga-E. coli shuttle vectors effectively transformed T. sp. strain RQ7, rendering the cells resistance to kanamycin. The kan gene carried by the shuttle vector pDH10 was detected by PCR from the plasmid extract of the transformants, and the amplicons were verified by restriction digestions. A procedure for natural transformation of Thermotoga spp. was established and optimized. With the optimized method, T. sp. strain RQ7 sustained a transformation frequency in the order of 10^-7 with both genomic and plasmid DNA.

Conclusions

T. sp. strain RQ7 cells are naturally transformable during their early exponential phase. They acquire DNA from both closely and distantly related species. Both chromosomal DNA and plasmid DNA serve as suitable substrates for transformation. Our findings lend a convenient technical tool for the genetic engineering of Thermotoga spp.

【 授权许可】

   
2014 Han et al.; licensee BioMed Central Ltd.

【 图 表 】

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