@article{open3099,
          volume = {205},
          number = {5},
           month = {April},
          author = {Mohinder Pal and Kumar Vinay Yadav  and Pramila Pal and Nisheeth Agarwal and Alka Rao},
            note = {The copyright of this article belongs to Springer Science},
           title = {The physiological effect of rimI/rimJ silencing by CRISPR interference in Mycobacterium smegmatis mc2155
},
       publisher = {Springer Science},
            year = {2023},
         journal = {Archives of microbiology},
        keywords = {CRISPRi; Drug resistance; Minimum inhibitory concentration; Mycobacterium; N-acetylation.},
             url = {http://crdd.osdd.net/open/3099/},
        abstract = {N-terminal acetylation of proteins is an important post-translational modification (PTM) found in eukaryotes and prokaryotes. In bacteria, N-terminal acetylation is suggested to play various regulatory roles related to protein stability, gene expression, stress response, and virulence; however, the mechanism of such response remains unclear. The proteins, namely RimI/RimJ, are involved in N-terminal acetylation in mycobacteria. In this study, we used CRISPR interference (CRISPRi) to silence rimI/rimJ in Mycobacterium smegmatis mc2155 to investigate the physiological effects of N-terminal acetylation in cell survival and stress response. Repeat analysis of growth curves in rich media and biofilm analysis in minimal media of various mutant strains and wild-type bacteria did not show significant differences that could be attributed to the rimI/rimJ silencing. However, total proteome and acetylome profiles varied significantly across mutants and wild-type strains, highlighting the role of RimI/RimJ in modulating levels of proprotein acetylation in the cellular milieu. Further, we observed a significant increase in the minimum inhibitory concentration (MIC) (from 64 to 1024 ?g ml-1) for the drug isoniazid in rimI mutant strains. The increase in MIC value for the drug isoniazid in the mutant strains suggests the link between N-terminal acetylation and antibiotic resistance. The study highlights the utility of CRISPRi as a convenient tool to study the role of PTMs, such as acetylation in mycobacteria. It also identifies rimI/rimJ genes as necessary for managing cellular response against antibiotic stress. Further research would be required to decipher the potential of targeting acetylation to enhance the efficacy of existing antibiotics.

}
}