ETH Zurich, Zurich, Switzerland.
PLoS Comput Biol. 2022 Feb 25;18(2):e1009857. doi: 10.1371/journal.pcbi.1009857. eCollection 2022 Feb.
Resource patchiness and aqueous phase fragmentation in soil may induce large differences local growth conditions at submillimeter scales. These are translated to vast differences in bacterial age from cells dividing every thirty minutes in close proximity to plant roots to very old cells experiencing negligible growth in adjacent nutrient poor patches. In this study, we link bacterial population demographics with localized soil and hydration conditions to predict emerging generation time distributions and estimate mean bacterial cell ages using mechanistic and heuristic models of bacterial life in soil. Results show heavy-tailed distributions of generation times that resemble a power law for certain conditions, suggesting that we may find bacterial cells of vastly different ages living side by side within small soil volumes. Our results imply that individual bacteria may exist concurrently with all of their ancestors, resulting in an archive of bacterial cells with traits that have been gained (and lost) throughout time-a feature unique to microbial life. This reservoir of bacterial strains and the potential for the reemergence of rare strains with specific functions may be critical for ecosystem stability and function.
资源斑块性和土壤水相碎裂可能会在亚毫米尺度上诱导局部生长条件产生巨大差异。这些差异会导致细菌年龄的巨大差异，从靠近植物根系的每 30 分钟分裂一次的细胞到相邻养分贫瘠斑块中生长缓慢的非常老的细胞。在这项研究中，我们将细菌种群动态与局部土壤和水合条件联系起来，以预测新兴的代时分布，并使用土壤中细菌生命的机理和启发式模型来估计平均细菌细胞年龄。结果表明，代时呈重尾分布，在某些条件下类似于幂律分布，这表明我们可能会发现，在小体积的土壤中，生活着具有巨大差异的细菌细胞。我们的结果表明，单个细菌可能与它们所有的祖先同时存在，从而在一个细菌细胞档案中保存了随着时间推移而获得（和失去）的特性——这是微生物生命所特有的特征。这种细菌菌株的储备以及具有特定功能的稀有菌株重新出现的潜力，可能对生态系统的稳定性和功能至关重要。
