Reduction in adaptor amounts establishes degradation hierarchy among protease substrates.

摘要: ATP-dependent proteases control critical cellular processes, including development, physiology, and virulence. A given protease may recognize a substrate directly via an unfoldase domain or subunit indirectly adaptor that delivers the to unfoldase. We now report cells achieve differential stability among substrates of by modulating amounts. establish regulatory protein PhoP represses transcription gene specifying ClpAP ClpS when bacteria Salmonella enterica Escherichia coli experience low cytoplasmic Mg2+. The resulting decrease in amounts diminishes proteolysis several ClpSAP-dependent substrates, putrescine aminotransferase Oat, which heightens formation antibiotic persisters, transcriptional regulators UvrY PhoP, alter expression genes controlled these proteins. By contrast, did not impact abundance ClpSAP FtsA, reflecting FtsA binds more tightly than PhoP. Our findings show how physiological conditions reduce modify selected protease.