Abstract：
Understanding intricate microbial interactions in the environment is crucial. This is especially true for the relationships between nutrients and bacteria, as phosphorus, nitrogen and organic carbon availability are known to influence bacterial population dynamics. It has been suggested that low nutrient conditions prompt the evolutionary process of genome streamlining. This process helps conserve scarce nutrients and allows for proliferation. Genome streamlining is associated with genomic properties such as %GC content, genes encoding sigma factors, percent coding regions, gene redundancy, and functional shifts in processes like cell motility and ATP binding cassette transporters, among others. The current study aims to unveil the impact of nutrition on the genome size, %GC content, and functional properties of pelagic freshwater bacteria. We do this at finer taxonomic resolutions for many metagenomically characterized communities. Our study confirms the interplay of trophic level and genomic properties. It also highlights that different nutrient types, particularly phosphorus and nitrogen, impact these properties differently. We observed a covariation of functional traits with genome size. Larger genomes exhibit enriched pathways for motility, environmental interaction, and regulatory genes. ABC transporter genes reflect the availability of nutrients in the environment, with small genomes presumably relying more on metabolites from other organisms. We also discuss the distinct strategies different phyla adopt to adapt to oligotrophic environments. The findings contribute to our understanding of genomic adaptations within complex microbial communities.
摘要：
了解环境中复杂的微生物相互作用至关重要。营养和细菌之间的关系尤其如此，作为磷，已知氮和有机碳可利用性会影响细菌种群动态。有人认为，低营养条件促使基因组精简的进化过程。这个过程有助于保存稀缺的营养物质并允许增殖。基因组精简与基因组特性相关，如%GC含量，编码西格玛因子的基因，百分比编码区域，基因冗余，以及细胞运动和ATP结合盒转运蛋白等过程的功能变化，在其他人中。目前的研究旨在揭示营养对基因组大小的影响，%GC含量,和中上层淡水细菌的功能特性。对于许多具有宏基因特征的社区，我们以更精细的分类学分辨率来做到这一点。我们的研究证实了营养水平和基因组特性的相互作用。它还强调了不同的营养类型，特别是磷和氮，对这些属性的影响不同。我们观察到功能性状与基因组大小的共变。较大的基因组表现出丰富的运动性途径，环境相互作用，和调节基因。ABC转运体基因反映了环境中营养物质的可用性，小基因组可能更多地依赖其他生物的代谢物。我们还讨论了不同门适应贫营养环境的不同策略。这些发现有助于我们理解复杂微生物群落中的基因组适应。
