Emiliania huxleyi is one of the most abundant marine planktons, and it has a crucial feature in the carbon cycle. However, proteomic analyses of Emiliania huxleyi have not been done extensively. In this study, a three-dimensional liquid chromatography (3D-LC) system consisting of strong cation exchange, high- and low-pH reversed-phase liquid chromatography was established for in-depth proteomic profiling of Emiliania huxleyi. From tryptic proteome digest, 70 fractions were generated and analyzed using liquid chromatography-tandem mass spectrometry. In total, more than 84,000 unique peptides and 10,000 proteins groups were identified with a false discovery rate of ≤0.01. The physicochemical properties of the identified peptides were evaluated. Using ClueGO, approximately 700 gene ontology terms and 15 pathways were defined from the identified protein groups with p-value ≤0.05, covering a wide range of biological processes, cellular components, and molecular functions. Many biological processes associated with CO2 fixation, photosynthesis, biosynthesis, and metabolic process were identified. Various molecular functions relating to protein binding and enzyme activities were also found. The 3D-LC strategy is a powerful approach for comparative proteomic studies on Emiliania huxleyi to reveal changes in its protein level and related mechanism.

中文翻译：

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使用三维分离方法结合串联质谱法对 Emiliania huxleyi 进行蛋白质组学分析

Emiliania huxleyi 是最丰富的海洋浮游生物之一，它在碳循环中具有关键特征。然而，尚未对 Emiliania huxleyi 进行广泛的蛋白质组学分析。在本研究中，建立了由强阳离子交换、高、低 pH 反相液相色谱组成的三维液相色谱 (3D-LC) 系统，用于对 Emiliania huxleyi 进行深入的蛋白质组学分析。从胰蛋白酶蛋白质组消化物中生成 70 个馏分，并使用液相色谱-串联质谱法进行分析。总共识别出 84,000 多个独特肽段和 10,000 个蛋白质组，错误发现率≤0.01。对鉴定出的肽的理化性质进行了评估。使用 ClueGO，从已鉴定的蛋白质组中定义了大约 700 个基因本体术语和 15 条通路，p 值≤0.05，涵盖了广泛的生物过程、细胞成分和分子功能。许多与 CO2 固定、光合作用、生物合成和代谢过程相关的生物过程被确定。还发现了与蛋白质结合和酶活性有关的各种分子功能。3D-LC 策略是对 Emiliania huxleyi 进行比较蛋白质组学研究以揭示其蛋白质水平和相关机制变化的有力方法。还发现了与蛋白质结合和酶活性有关的各种分子功能。3D-LC 策略是对 Emiliania huxleyi 进行比较蛋白质组学研究以揭示其蛋白质水平和相关机制变化的有力方法。还发现了与蛋白质结合和酶活性有关的各种分子功能。3D-LC 策略是对 Emiliania huxleyi 进行比较蛋白质组学研究以揭示其蛋白质水平和相关机制变化的有力方法。