Marciano Shir, Dey Debabrata, Listov Dina, Fleishman Sarel J, Sonn-Segev Adar, Mertens Haydyn, Busch Florian, Kim Yongseok, Harvey Sophie R, Wysocki Vicki H, Schreiber Gideon
Department of Biomolecular Sciences, Weizmann Institute of Science Rehovot Israel
Refeyn Ltd 1 Electric Avenue, Ferry Hinksey Road Oxford OX2 0BY UK.
Chem Sci. 2022 Sep 21;13(39):11680-11695. doi: 10.1039/d2sc02794a. eCollection 2022 Oct 12.
Over half the proteins in the cytoplasm form homo or hetero-oligomeric structures. Experimentally determined structures are often considered in determining a protein's oligomeric state, but static structures miss the dynamic equilibrium between different quaternary forms. The problem is exacerbated in homo-oligomers, where the oligomeric states are challenging to characterize. Here, we re-evaluated the oligomeric state of 17 different bacterial proteins across a broad range of protein concentrations and solutions by native mass spectrometry (MS), mass photometry (MP), size exclusion chromatography (SEC), and small-angle X-ray scattering (SAXS), finding that most exhibit several oligomeric states. Surprisingly, some proteins did not show mass-action driven equilibrium between the oligomeric states. For approximately half the proteins, the predicted oligomeric forms described in publicly available databases underestimated the complexity of protein quaternary structures in solution. Conversely, AlphaFold multimer provided an accurate description of the potential multimeric states for most proteins, suggesting that it could help resolve uncertainties on the solution state of many proteins.
细胞质中超过一半的蛋白质形成同源或异源寡聚体结构。在确定蛋白质的寡聚状态时，通常会考虑实验测定的结构，但静态结构忽略了不同四级结构形式之间的动态平衡。在同源寡聚体中，这个问题更加严重，因为寡聚状态的特征很难确定。在这里，我们通过原生质谱（MS）、质量光度法（MP）、尺寸排阻色谱法（SEC）和小角X射线散射（SAXS），在广泛的蛋白质浓度和溶液范围内重新评估了17种不同细菌蛋白质的寡聚状态，发现大多数蛋白质呈现出几种寡聚状态。令人惊讶的是，一些蛋白质在寡聚状态之间没有表现出质量作用驱动的平衡。对于大约一半的蛋白质，公开数据库中描述的预测寡聚形式低估了溶液中蛋白质四级结构的复杂性。相反，AlphaFold多聚体对大多数蛋白质的潜在多聚状态提供了准确的描述，这表明它有助于解决许多蛋白质溶液状态的不确定性。
