1ox9

Structural highlights

Function

SSPB_ECOLI Enhances recognition of ssrA-tagged proteins by the ClpX-ClpP protease; the ssrA degradation tag (AANDENYALAA) is added trans-translationally to proteins that are stalled on the ribosome, freeing the ribosome and targeting stalled peptides for degradation. SspB activates the ATPase activity of ClpX. Seems to act in concert with SspA in the regulation of several proteins during exponential and stationary-phase growth.^{[1] [2] [3]} Also stimulates degradation of the N-terminus of RseA (residues 1-108, alone or in complex with sigma-E) by ClpX-ClpP in a non-ssrA-mediated fashion.^{[4] [5] [6]}

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

See Also

• Stringent starvation protein 3D structures

References

1. ↑ Levchenko I, Seidel M, Sauer RT, Baker TA. A specificity-enhancing factor for the ClpXP degradation machine. Science. 2000 Sep 29;289(5488):2354-6. PMID:11009422
2. ↑ Flynn JM, Levchenko I, Sauer RT, Baker TA. Modulating substrate choice: the SspB adaptor delivers a regulator of the extracytoplasmic-stress response to the AAA+ protease ClpXP for degradation. Genes Dev. 2004 Sep 15;18(18):2292-301. PMID:15371343 doi:http://dx.doi.org/10.1101/gad.1240104
3. ↑ Song HK, Eck MJ. Structural basis of degradation signal recognition by SspB, a specificity-enhancing factor for the ClpXP proteolytic machine. Mol Cell. 2003 Jul;12(1):75-86. PMID:12887894
4. ↑ Levchenko I, Seidel M, Sauer RT, Baker TA. A specificity-enhancing factor for the ClpXP degradation machine. Science. 2000 Sep 29;289(5488):2354-6. PMID:11009422
5. ↑ Flynn JM, Levchenko I, Sauer RT, Baker TA. Modulating substrate choice: the SspB adaptor delivers a regulator of the extracytoplasmic-stress response to the AAA+ protease ClpXP for degradation. Genes Dev. 2004 Sep 15;18(18):2292-301. PMID:15371343 doi:http://dx.doi.org/10.1101/gad.1240104
6. ↑ Song HK, Eck MJ. Structural basis of degradation signal recognition by SspB, a specificity-enhancing factor for the ClpXP proteolytic machine. Mol Cell. 2003 Jul;12(1):75-86. PMID:12887894