iProXProteomicsJie YuLactobacillus Paracaseihttp://www.iprox.org/page/project.html?id=IPX0014371000nmgnd2022@126.comInner Mongolia Agricultural UniversityiProXThe importance of lysine 2-hydroxyisobutyrylation (Khib) in regulating biological processes has become increasingly apparent, but its functional significance in prokaryotes, especially in the Lactobacillus paracasei PC-01, is poorly understood. In this study, the regulatory mechanism of Khib in high-density fermentation of L. paracasei PC-01 was investigated using mass spectrometry proteomics. In total, 6783 Khib sites on 1361 proteins were identified, with 73.48% proteins containing multiple sites. GO and KEGG enrichment analysis showed Khib affected cellular functions and metabolic pathways, especially those involved in ribosomal activity and protein biosynthesis. Subsequently, a Khib-mediated regulatory network of L. paracasei PC-01 revealed most of the significantly upregulated enzymes in the glycolysis, TCA cycle, purine metabolism, amino acid metabolism, and fatty acid biosynthesis pathways were modified by Khib. This study elucidated the biological function of Khib modification in L. paracasei during high-density cultures and provides theoretical basis for the preparation of highly active probiotic preparations.Global lysine 2-hydroxyisobutyrylation profiling reveals the growth mechanism of Lactobacillus paracasei PC-01 in high-density cultures.Shen Shijia S, Zhou Runzhi R, Wang Hua H, Li Hongyang H, Gao Shuaisen S, Yu Jie JfalseGlobal Lysine 2-Hydroxyisobutyrylation Profiling Reveals the Growth Mechanism of Lactobacillus paracasei PC-01 in High-density CulturesWe confirmed that Khib PTM occurs during high-density fermentation of L. paracasei. Based on mass-spectrometry-based proteomics, Khib was fully characterized in L. paracasei PC-01 for the first time, and in total 6783 Khib sites on 1361 proteins were identified.Mon Jan 26 00:00:00 GMT 2026PXD073628159741638391