Bacteria are simple organisms, optimized with basic but robust cell
regulation mechanisms for efficient growth. Nonetheless, fitting in the description, they
possess remarkable adaptive capacity with diverse survival strategies. Post-translational
modifications (PTMs) provide a competitive edge to adapt bacteria with limiting,
fluctuating nutrients and extremes of environment variables. PTM is one of the cellular
processes in bacteria and helps them to adapt to a new environment for their survival.
Several post-translation modifications regulate bacterial functions and provide strength
to bacteria for surviving in adverse conditions. On-going investigations revealed many
reversible or irreversible novel bacterial PTMs like the addition of simple group
(acetylation, phosphorylation, methylation and hydroxylation) or composite molecules
(AMPylation, ADP-ribosylation, glycosylation and isoprenylation), or small protein
ubiquitin and modifying the side chain residues like (elimination and deamidation).
PTMs are recognized as important players in directing cellular dynamics like cell
metabolism, stress response, pathogenesis and virulence factors. Bacteria with several
PTMs are capable of modulating the signaling pathways by destabilising the host cell
defense machinery, protein-protein interactions, ultimately promoting their replication.
Currently, many studies focus on the relationship between PTMs and antibiotic
resistance, increasing bacterial tolerance to various antimicrobials. A paradoxical
behaviour is that a single protein may be modified at one or variable positions in
interspecies, but changes also exist in the same species. So, to characterize the
multifaceted interactions of PTMs, it is still a challenge in metabolic engineering, synthetic biology, and medical sciences. Therefore, understanding of bacterial PTMs
and PTMs directed host proteins modification will provide better insights into hostpathogen
interaction. This chapter focuses on the roles of PTMs in nutrition
sequestration and cellular response. Furthermore, we discuss the prospects and
advances of proteomics tools in enhancing knowledge related to PTMs of human gut
microbiota.
Keywords: Acetylation, Carboxylation, Glycosylation, Interactomics, Lipidation,
Methylation, Microbial proteins, Nitrosylation, Phosphorylation, Posttranslational
modifications, Proteomic tools.
