School of Life Sciences, Ningxia University, Yinchuan 750021, China.
Int J Mol Sci. 2023 May 8;24(9):8446. doi: 10.3390/ijms24098446.
Lysine malonylation (Kmal) is an evolutionarily conserved post-translational modification (PTM) that has been demonstrated to be involved in cellular and organismal metabolism. However, the role that Kmal plays in response to drought stress of the terrestrial cyanobacteria is still unknown. In this study, we performed the first proteomic analysis of Kmal in under different drought stresses using LC-MS/MS. In total, 421 malonylated lysine residues were found in 236 different proteins. GO and KEGG enrichment analysis indicated that these malonylated proteins were highly enriched in several metabolic pathways, including carbon metabolism and photosynthesis. Decreased malonylation levels were found to hinder the reception and transmission of light energy and CO fixation, which led to a decrease in photosynthetic activity. Kmal was also shown to inhibit the flux of the TCA cycle and activate the gluconeogenesis pathway in response to drought stress. Furthermore, malonylated antioxidant enzymes and antioxidants were synergistically involved in reactive oxygen species (ROS) scavenging. Malonylation was involved in lipid degradation and amino acid biosynthesis as part of drought stress adaptation. This work represents the first comprehensive investigation of the role of malonylation in dehydrated , providing an important resource for understanding the drought tolerance mechanism of this organism.
赖氨酸丙二酰化（Kmal）是一种进化上保守的翻译后修饰（PTM），已被证明参与细胞和机体代谢。然而，Kmal 在陆地蓝藻应对干旱胁迫中的作用尚不清楚。在这项研究中，我们使用 LC-MS/MS 首次对不同干旱胁迫下的 中的 Kmal 进行了蛋白质组学分析。总共在 236 种不同的蛋白质中发现了 421 个丙二酰化赖氨酸残基。GO 和 KEGG 富集分析表明，这些丙二酰化蛋白高度富集在几种代谢途径中，包括碳代谢和光合作用。丙二酰化水平的降低被发现阻碍了光能的接收和传递以及 CO2 的固定，从而导致光合作用活性下降。Kmal 还被证明能够抑制三羧酸（TCA）循环的通量并在干旱胁迫下激活糖异生途径。此外，丙二酰化抗氧化酶和抗氧化剂协同参与活性氧（ROS）的清除。丙二酰化参与了脂质降解和氨基酸生物合成，作为干旱胁迫适应的一部分。这项工作代表了对脱水 中丙二酰化作用的首次全面研究，为理解该生物的耐旱机制提供了重要资源。
