The role of post-translational modifications in aquatic bacterial pathogens

Significance Bacterial infections pose a severe threat to human health and cause significant economic losses in aquaculture. Deciphering the molecular pathogenic mechanisms of aquatic bacterial pathogens is crucial for developing precise prevention and control strategies. With advancements in proteomics and mass spectrometry, post-translational modifications (PTMs) have emerged as pivotal molecular mechanisms regulating the pathogenic processes of these bacteria. Therefore, systematically summarizing research progress on PTMs in aquatic bacterial pathogenesis will deepen our understanding of infection mechanisms and provide novel insights for developing control measures.

Progress Studies demonstrate that PTMs such as phosphorylation, acetylation, succinylation, and glycosylation are widespread in aquatic bacterial pathogens. These modifications influence pathogenesis by modulating protein conformation, activity, and interactions. In virulence regulation: Acetylation and succinylation of nucleoid-associated proteins (NAPs) alter their DNA-binding capacity, thereby regulating the silencing or activation of virulence genes. Key components of Two-Component Systems (TCS) and Quorum Sensing (QS) pathways undergo PTMs to mediate signal transduction. PTMs on transcription factors affect their stability and DNA-binding ability, modulating the transcription of virulence factors. Modifications on virulence factors themselves directly regulate their activity and infectivity. In pathogen-host interaction: PTMs participate in metabolic reprogramming and environmental adaptation of the pathogen. Glycosylation modifications of surface structural proteins and flagella impact host immune recognition and bacterial immune evasion. Notably, host cells can actively mediate PTMs on bacterial effector proteins, altering their subcellular localization and function to promote infection. Furthermore, complex crosstalk exists between different PTM types. They can act synergistically or antagonistically on the same protein or residue, forming dynamic regulatory networks that provide a molecular basis for pathogen adaptation to the host microenvironment and enhanced infectivity.

Perspect While PTMs play critical roles in the pathogenesis of aquatic bacterial pathogens, current research remains largely confined to a limited number of modification types and bacterial species. Future studies should broaden the scope to include diverse PTMs and pathogens, integrate multi-omics approaches with relevant infection models to reveal dynamic regulatory networks, and deeply explore the mechanisms of PTM crosstalk. Systematic investigation of PTMs will not only elucidate bacterial pathogenic mechanisms but also offer novel targets and a theoretical foundation for controlling aquatic bacterial diseases.