College of Medicine, QU Health, Qatar University, Doha, Qatar.
Interim Translational Research Institute, Hamad Medical Corporation, Doha, Qatar.
Protein Pept Lett. 2022;29(5):473-484. doi: 10.2174/0929866529666220318152509.
This study aims to identify novel post-translational modifications in human serum albumin by mass spectrometry.
Serum albumin is the most abundant protein in plasma, has many physiological functions, and is in contact with most of the cells and tissues of the human body. Post-translational modifications (PTMs) may affect functions, stability, and localization of albumin.
Human serum albumin (HSA) was used for tryptic digestion in-solution or in-gel. Mass spectrometry was applied to identify PTMs in HSA. 3-dimensional modeling was applied to explore the potential impact of PTMs on known functions of albumin.
Here, we report the identification of 61 novel PTMs of human serum albumin. Phosphorylation, glycosylation, nitrosylation, deamidation, methylation, acetylation, palmitoylation, geranylation, and farnesylation are some examples of the identified PTMs. Mass spectrometry was used for the identification of PTMs in a purified HSA and HSA from the human plasma. Threedimensional modeling of albumin with selected PTMs showed the location of these PTMs in the regions involved in albumin interactions with drugs, metals, and fatty acids. The location of PTMs in these regions may modify the binding capacity of albumin.
This report adds 61 novel PTMs to the catalog of human albumin.
本研究旨在通过质谱法鉴定人血清白蛋白中的新型翻译后修饰。
血清白蛋白是血浆中最丰富的蛋白质，具有许多生理功能，与人体的大多数细胞和组织都有接触。翻译后修饰（PTMs）可能会影响白蛋白的功能、稳定性和定位。
采用溶液或胶内胰蛋白酶消化法对人血清白蛋白（HSA）进行消化。应用质谱法鉴定 HSA 中的 PTMs。应用三维建模探索 PTMs 对白蛋白已知功能的潜在影响。
本研究报告了 61 种人血清白蛋白新型翻译后修饰的鉴定。鉴定出的 PTMs 包括磷酸化、糖基化、硝化、脱酰胺、甲基化、乙酰化、棕榈酰化、香叶基化、法尼基化等。本研究采用质谱法鉴定了纯化 HSA 和人血浆 HSA 中的 PTMs。对选定 PTMs 的白蛋白进行三维建模，显示了这些 PTMs 在与药物、金属和脂肪酸相互作用的白蛋白区域的位置。这些区域中 PTMs 的位置可能会改变白蛋白的结合能力。
本报告在人白蛋白的目录中添加了 61 种新型 PTMs。
