摘要

    肺炎克雷伯氏菌是一种重要的耐多药病原体，携带有前噬菌体。在这里，我们探讨了噬菌体对细菌进化和计算机适应性的贡献。这项研究表明，噬菌体有助于肺炎克雷伯菌的显着基因组可塑性。 CG258菌株拥有几个保守的原噬菌体，包括一对P2-P4的原噬菌体。 CRISPR-Cas系统对预噬的影响有限。 CRISPR-Cas和原噬菌体的强烈依赖MLST的分布以及带有自定位间隔子的高比例菌株可能是原因。在几乎所有染色体上都检测到四个核心ARG（blaSHV，fosA和oqxAB），但获得的ARG仅在CG258和CRISPR阳性菌株中发现。影响CG258和CRISPR阳性菌株中ARGs染色体整合的因素可能不同。在CG258中，噬菌体可能涉及ARG的染色体整合。对于CRISPR阳性菌株，CRISPR-Cas系统对入侵带有ARG的移动遗传元件的免疫力可能会加速这一过程。

    Klebsiella pneumoniae is an important multidrug-resistant pathogen carrying prophages. Here we explore the contribution of prophages to bacterial evolution and fitness in silico. This study showed prophages contribute to remarkable genome plasticity of K. pneumoniae. The strains of CG258 possess several conserved prophages including the couple of P2-P4 prophages. CRISPR-Cas system has limited impact on the presence of prophages. The strong MLST-depended distribution of CRISPR-Cas and prophages and the high proportion of strains with self-targeting spacers may be the causes. Four core ARGs (blaSHV, fosA and oqxAB) were detected on almost all the chromosomes, but the acquired ARGs were only found in CG258 and CRISPR-positive strains. The factors influencing the chromosomal integration of ARGs in CG258 and CRISPR-positive strains may be different. In CG258, prophages may involve the chromosomal integration of ARGs. For CRISPR-positive strains, the immunity of CRISPR-Cas systems against invading ARG-bearing mobile genetic elements may accelerate the process.

    https://www.sciencedirect.com/science/article/abs/pii/S0888754318307225