Wu Weichao, Dijkstra Paul, Hungate Bruce A, Shi Lingling, Dippold Michaela A
Biogeochemistry of Agroecosystem, University of Goettingen, Goettingen, Germany.
Department of Environmental Science, Stockholm University, Stockholm, Sweden.
Sci Adv. 2022 Nov 4;8(44):eabq3958. doi: 10.1126/sciadv.abq3958.
The central carbon (C) metabolic network harvests energy to power the cell and feed biosynthesis for growth. In pure cultures, bacteria use some but not all of the network's major pathways, such as glycolysis and pentose phosphate and Entner-Doudoroff pathways. However, how these pathways are used in microorganisms in intact soil communities is unknown. Here, we analyzed the incorporation of C from glucose isotopomers into phospholipid fatty acids. We showed that groups of Gram-positive and Gram-negative bacteria in an intact agricultural soil used different pathways to metabolize glucose. They also differed in C use efficiency (CUE), the efficiency with which a substrate is used for biosynthesis. Our results provide experimental evidence for diversity among microbes in the organization of their central carbon metabolic network and CUE under in situ conditions. These results have important implications for our understanding of how community composition affects soil C cycling and organic matter formation.
中心碳（C）代谢网络获取能量为细胞提供动力，并为生长提供生物合成所需的物质。在纯培养物中，细菌会使用该网络的一些但并非全部主要途径，例如糖酵解、磷酸戊糖途径和恩特纳-杜德洛夫途径。然而，在完整的土壤群落中，微生物如何利用这些途径尚不清楚。在这里，我们分析了葡萄糖同位素异构体中的碳掺入磷脂脂肪酸的情况。我们发现，完整农业土壤中的革兰氏阳性菌和革兰氏阴性菌群利用不同的途径代谢葡萄糖。它们在碳利用效率（CUE）方面也存在差异，即底物用于生物合成的效率。我们的结果为原位条件下微生物中心碳代谢网络组织和CUE的多样性提供了实验证据。这些结果对于我们理解群落组成如何影响土壤碳循环和有机质形成具有重要意义。
