Center for Studies in Physics and Biology, Rockefeller University, New York, NY, USA.
Department of Computer Science, University of California Los Angeles, Los Angeles, CA, USA.
Science. 2020 Nov 6;370(6517):683-687. doi: 10.1126/science.aaz9642.
Nutrient limitation drives competition for resources across organisms. However, much is unknown about how selective pressures resulting from nutrient limitation shape microbial coding sequences. Here, we study this "resource-driven selection" by using metagenomic and single-cell data of marine microbes, alongside environmental measurements. We show that a significant portion of the selection exerted on microbes is explained by the environment and is associated with nitrogen availability. Notably, this resource conservation optimization is encoded in the structure of the standard genetic code, providing robustness against mutations that increase carbon and nitrogen incorporation into protein sequences. This robustness generalizes to codon choices from multiple taxa across all domains of life, including the human genome.
营养限制驱动着生物体之间对资源的竞争。然而，对于营养限制所产生的选择性压力如何塑造微生物编码序列，我们知之甚少。在这里，我们通过使用海洋微生物的宏基因组和单细胞数据以及环境测量数据来研究这种“资源驱动的选择”。我们表明，环境解释了对微生物施加的选择的很大一部分，并且与氮的可利用性有关。值得注意的是，这种资源保护优化被编码在标准遗传密码的结构中，提供了对增加碳和氮掺入蛋白质序列的突变的稳健性。这种稳健性适用于来自所有生命领域的多个分类群的密码子选择，包括人类基因组。
