Awan Ayesha, Bartlett Alexandria, Blakeley-Ruiz J Alfredo, Richie Tanner, Theriot Casey M, Kleiner Manuel
Department of Plant and Microbial Biology, College of Agriculture and Life Sciences, North Carolina State University, Raleigh, NC, 27606, USA.
Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, 27710, USA.
Food Funct. 2025 Sep 1. doi: 10.1039/d5fo01132a.
Protein is an essential macronutrient and variations in its source and quantity have been shown to impact long-term health outcomes. Differential health impacts of dietary proteins from various sources are likely driven by differences in their digestibility by the host and subsequent availability to the intestinal microbiota. However, our current understanding regarding the fate of dietary proteins from different sources in the gut, specifically how component proteins within these sources interact with the host and the gut microbiota, is limited. To determine which dietary proteins are efficiently digested by the host, and which proteins escape host digestion and are used by the gut microbiota, we used high-resolution mass spectrometry to quantify proteins that constitute different dietary protein sources before and after digestion in germ-free and conventionally raised mice. We detected proteins from all sources in fecal samples of both germ-free and conventional mice suggesting that even protein sources with high digestive efficiency make it to the colon where they can serve as metabolic substrate for gut microbiota. Additionally, we found that specific component proteins of dietary protein sources were degraded to a greater extent in the presence of the microbiota. We found that specific proteins with functions that could potentially impact host health and physiology were differentially enriched in germ-free or conventionally raised mice. These findings reveal large differences in the fate of dietary protein from various sources in the gut which could explain some of their differential health impacts.
蛋白质是一种必需的宏量营养素，其来源和数量的变化已被证明会影响长期健康结果。不同来源的膳食蛋白质对健康的不同影响可能是由宿主对其消化率以及随后肠道微生物群可利用性的差异所驱动的。然而，我们目前对不同来源的膳食蛋白质在肠道中的命运，特别是这些来源中的组成蛋白质如何与宿主和肠道微生物群相互作用的理解是有限的。为了确定哪些膳食蛋白质能被宿主有效消化，哪些蛋白质能逃过宿主消化而被肠道微生物群利用，我们使用高分辨率质谱法对无菌小鼠和常规饲养小鼠消化前后构成不同膳食蛋白质来源的蛋白质进行了定量。我们在无菌小鼠和常规小鼠的粪便样本中都检测到了所有来源的蛋白质，这表明即使是消化效率高的蛋白质来源也能到达结肠，在那里它们可以作为肠道微生物群的代谢底物。此外，我们发现膳食蛋白质来源的特定组成蛋白质在有微生物群存在的情况下降解程度更大。我们发现具有可能影响宿主健康和生理功能的特定蛋白质在无菌小鼠或常规饲养小鼠中存在差异富集。这些发现揭示了不同来源的膳食蛋白质在肠道中的命运存在巨大差异，这可以解释它们对健康的一些不同影响。
