A Systematic Study of Lysine Succinylation in the Pathogenic Bacterium Vibrio harveyi in Aquatic Animals

<i>Vibrio harveyi,</i> a pathogenic vibrio, is ubiquitous and the most prevalent disease infecting tropical and subtropical mariculture animals in marine and estuarine environments. It presents a major risk to mariculture companies worldwide and can cause serious disease problems in aquaculture. Recent studies have shown that various pathogens employ post-translational modifications (PTMs) to regulate cellular processes. One of the major PTMs is lysine succinylation, which is widespread in eukaryotic and prokaryotic cells. Many basic biological functions of bacteria are associated with the regulation of lysine (K) succinylation (Ksuc). However, little is known about the role of lysine succinylation in <i>V. harveyi</i> pathogenesis. Here, we performed LC-MS/MS analysis of 1271 proteins from <i>V. harveyi</i> to identify 4252 Ksuc modification sites. The modification of S-ribosylhomocysteine lyase (LuxS) and transcription elongation factor GreA proteins by Ksuc was confirmed through immunoprecipitation combined with Western blot, further validating our proteomics results. Bioinformatics study revealed that the identified Ksuc proteins play roles in multiple cellular processes and vital metabolic pathways, including LuxS, biofilm exopolysaccharide biosynthesis protein EpsG, and the general secretory system (Sec systems), and are proteins that regulate bacterial virulence. Generally, this scientific study serves as the basis for additional research on the pathogenic nature of Ksuc in <i>V. harveyi</i> and reveals potential targets that would accelerate the manufacturing of attenuated vaccines.