摘要

人类病原体鲍曼不动杆菌（Acinetobacter baumannii）具有很高的遗传可塑性，并且经常获得抗生素抗性基因。在这里，我们研究自然转化在这些过程中的作用。将来自不同来源的基因组DNA（gDNA）与来自碳青霉烯抗性肺炎克雷伯氏菌（CRKp）菌株的基因组DNA（gDNA）与鲍氏不动杆菌A118细胞混合。通过全基因组测序分析选择的转化体。此外，还进行了生物信息学分析和计算机基因流预测以支持我们的实验结果。转化株包括一些对碳青霉烯具有抗性或改变了抗生素敏感性的菌株。通过全基因组分析证实了外源DNA的获得。最常识别的获得的DNA对应于移动元件，抗生素抗性基因和参与代谢的操纵子。生物信息学分析和计算机基因流预测表明，当鲍曼不动杆菌和肺炎克雷伯氏菌共享相同的栖息地时，遗传物质将继续交换。自然转化在鲍曼不动杆菌的可塑性中起重要作用，同时在MDR菌株的出现中起重要作用。

The human pathogen Acinetobacter baumannii possesses high genetic plasticity and frequently acquires antibiotic resistance genes. Here, we investigate the role of natural transformation in these processes. Genomic DNA (gDNA) from different sources including that from carbapenem-resistant Klebsiella pneumoniae (CRKp) strains was mixed with A. baumannii A118 cells. Selected transformants were analyzed by whole genome sequencing. In addition, bioinformatic analyses and in silico gene flow prediction were also performed to support our experimental results. Transformant strains included some that became resistant to carbapenem or changed the antibiotic susceptibility profile. Foreign DNA acquisition was confirmed by whole genome analysis. The acquired DNA that was most frequently identified corresponded to mobile elements, antibiotic resistance genes, and operons involved in metabolism. Bioinformatic analyses and in silico gene flow prediction showed continued exchange of genetic material between A. baumannii and K. pneumoniae when they share the same habitat. Natural transformation plays an important role in the plasticity of A. baumannii and concomitantly in the emergence of MDR strains.

https://www.ncbi.nlm.nih.gov/pubmed/30611868