Functional Cooperativity between the Trigger Factor Chaperone and the ClpXP Proteolytic Complex

A functional association is uncovered between the ribosome-associated trigger factor (TF) chaperone and ClpXP degradation complex. Bioinformatic analyses demonstrates conservation of close proximity tig, gene coding for TF, genes suggesting a interaction. Effect TF on ClpXP-dependent varies based nature substrate. While some substrates are slowed down or unaffected by surprisingly, increases rate third class substrates. These include λ phage replication protein λO, master regulator stationary phase RpoS, SsrA-tagged proteins. Globally, acts to enhance about 2% newly synthesized found interact through multiple sites with ClpX in highly dynamic fashion promote degradation. This chaperone-protease cooperation constitutes unique likely ancestral aspect cellular homeostasis which as an adaptor ClpXP.