ClpP participates in stress tolerance, biofilm formation, antimicrobial tolerance, and virulence of Enterococcus faecalis

Abstract

Background ClpP is important for bacterial growth and plays an indispensable role in cellular protein quality control systems by refolding or degrading damaged proteins, but the physiological significance of ClpP in Enterococcus faecalis remains obscure. A clpP deletion mutant (△ clpP ) was constructed using the E. faecalis OG1RF strain to clarify the effect of ClpP on E. faecalis. The global abundance of proteins was determined by a mass spectrometer with tandem mass tag labeling.Results The Δ clpP mutant strain showed impaired growth at 20°C or 45°C at 5% NaCl or 2 mM H 2 O 2 . The number of surviving Δ clpP mutants decreased after exposure to the high concentration (50× minimal inhibitory concentration) of linezolid or minocycline for 96 h. The Δ clpP mutant strain also demonstrated decreased biofilm formation but increased virulence in a Galleria mellonella model. The mass spectrometry proteomics data indicated that the abundances of 135 proteins changed (111 increased, 24 decreased) in the Δ clpP mutant strain. Among those, the abundances of stress response or virulence relating proteins: FsrA response regulator, gelatinase GelE, regulatory protein Spx ( spxA ), heat-inducible transcription repressor HrcA, transcriptional regulator CtsR, ATPase/chaperone ClpC, acetyl esterase/lipase, and chaperonin GroEL increased in the Δ clpP mutant strain; however, the abundances of ribosomal protein L4/L1 family protein ( rplD ), ribosomal protein L7/L12 ( rplL2 ), 50S ribosomal protein L13 ( rplM ), L18 ( rplR ), L20 ( rplT ), 30S ribosomal protein S14 ( rpsN2 ) and S18 ( rpsR ) all decreased. The abundances of biofilm formation-related adapter protein MecA increased, while the abundances of dihydroorotase ( pyrC ), orotate phosphoribosyltransferase ( pyrE ), and orotidine-5'-phosphate decarboxylase ( pyrF ) all decreased in the Δ clpP mutant strain.Conclusion The present study demonstrates that ClpP participates in stress tolerance, biofilm formation, antimicrobial tolerance, and virulence of E. faecalis.

ClpL is a functionally active tetradecameric AAA+ chaperone, distinct from hexameric/dodecameric ones

“…Structural and biochemical studies on HSP100 chaperones have demonstrated that HSP100 chaperones operate as hexamer‐based oligomers. The crystal structure of ClpA from E coli revealed a hexameric assembly 16 . ClpA is associated with ClpP, a protease, serving as degradation machinery 17 .…”

Loss of ClpP Function inClostridioides difficile630 Significantly Impacts Sporulation Systems

“…Label-free quantitative proteomic analysis shows, the clpP1 mutant exhibits 84 significantly up- and 16 significantly down-regulated proteins ( Figure 5D ), the clpP2 mutant reveals 91 significantly up- and 17 significantly down-regulated proteins ( Figure 5E ), and the clpP1/clpP2 double mutant exhibits 99 significantly up-regulated and 42 significantly down-regulated proteins ( Figure 5F ) when compared with the WT. While proteins impacted by loss of ClpP function have been investigated in other organisms (Weichart, Querfurth et al 2003, Kock, Gerth et al 2004, Feng, Michalik et al 2013, Zheng, Wu et al 2020, Kirsch, Fetzer et al 2021), this is the first data set demonstrates the impact of ClpP absence on C. difficile .…”