The near‐minimal bacterium Mesoplasma florum is an interesting model for synthetic genomics and systems biology due to its small genome (~ 800 kb), fast growth rate, and lack of pathogenic potential. However, fundamental aspects of its biology remain largely unexplored. Here, we report a broad yet remarkably detailed characterization of M. florum by combining a wide variety of experimental approaches. We investigated several physical and physiological parameters of this bacterium, including cell size, growth kinetics, and biomass composition of the cell. We also performed the first genome‐wide analysis of its transcriptome and proteome, notably revealing a conserved promoter motif, the organization of transcription units, and the transcription and protein expression levels of all protein‐coding sequences. We converted gene transcription and expression levels into absolute molecular abundances using biomass quantification results, generating an unprecedented view of the M. florum cellular composition and functions. These characterization efforts provide a strong experimental foundation for the development of a genome‐scale model for M. florum and will guide future genome engineering endeavors in this simple organism.

中文翻译：

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近乎最小的细菌中原体的综合表征

由于其基因组小（约 800 kb）、生长速度快且缺乏致病潜力，近乎最小的细菌Mesoplasma florum是合成基因组学和系统生物学的一个有趣模型。然而，其生物学的基本方面在很大程度上仍未被探索。在这里，我们通过结合多种实验方法报告了M. florum的广泛但非常详细的表征。我们研究了这种细菌的几个物理和生理参数，包括细胞大小、生长动力学和细胞的生物量组成。我们还对其转录组和蛋白质组进行了首次全基因组分析，特别揭示了保守的启动子基序、转录单位的组织以及所有蛋白质编码序列的转录和蛋白质表达水平。我们利用生物量定量结果将基因转录和表达水平转换为绝对分子丰度，从而对M. florum细胞组成和功能产生了前所未有的认识。这些表征工作为开发M. florum基因组规模模型提供了坚实的实验基础，并将指导未来在这种简单生物体中的基因组工程工作。