Soil microbes, and the proteins they produce, are responsible for a myriad of soil processes which are integral to life on Earth, supporting soil fertility, nutrient fluxes, trace gas emissions, and plant production. However, how and why the composition of soil microbial proteins (the metaproteome) changes across wide gradients of vegetation, climatic and edaphic conditions remains largely undetermined. By applying high-resolution mass spectrometry to soil samples collected from four continents, we identified the most common proteins in soils, and investigated the primary environmental factors driving their distributions across climate and vegetation types. We found that soil proteins involved in carbohydrate metabolism, DNA repair, lipid metabolism, transcription regulation, tricarboxylic acid cycling, nitrogen (N) fixation and one-carbon metabolism dominate soils across a wide range of climates, vegetation types and edaphic conditions. Vegetation type and climate were important factors determining the community composition of the topsoil metaproteome. Moreover, we show that vegetation type, climate, and key edaphic proporties (mainly soil C fractions, pH and texture) influenced the proportion of important proteins involved in biogeochemical cycles and cellular processes. We also found that protein-based taxonomic information based on proteins has a greater resolution than 16S rRNA gene sequencing with regards to the ability to detect significant correlations with environmental variables. Together, our work identifies the dominant proteins produced by microbes living in a wide range of soils, and advances our understanding of how environmental changes can influence the structure and function of the topsoil metaproteome and the soil processes that they support.

土壤微生物及其产生的蛋白质负责无数土壤过程，这些过程是地球上生命不可或缺的一部分，支持土壤肥力、养分通量、微量气体排放和植物生产。然而，土壤微生物蛋白质（元蛋白质组）的组成如何以及为何在植被、气候和土壤条件的宽梯度范围内发生变化，在很大程度上仍未确定。通过对从四大洲收集的土壤样品应用高分辨率质谱，我们确定了土壤中最常见的蛋白质，并研究了驱动它们在气候和植被类型中分布的主要环境因素。我们发现土壤蛋白质参与碳水化合物代谢、DNA 修复、脂质代谢、转录调控、三羧酸循环、在各种气候、植被类型和土壤条件下，氮 (N) 固定和一碳代谢在土壤中占主导地位。植被类型和气候是决定表土宏蛋白质组群落组成的重要因素。此外，我们表明植被类型、气候和关键土壤比例（主要是土壤 C 分数、pH 值和质地）影响了参与生物地球化学循环和细胞过程的重要蛋白质的比例。我们还发现，在检测与环境变量显着相关性的能力方面，基于蛋白质的基于蛋白质的分类信息比 16S rRNA 基因测序具有更高的分辨率。我们的工作共同确定了生活在各种土壤中的微生物产生的主要蛋白质，