| Structural highlights
4qos is a 1 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , , |
| Related: | 2bjw, 2bjv, 2c98, 2c96, 2c99, 2c9c, 4qnm, 4qnr |
| Resources: | FirstGlance, OCA, RCSB, PDBsum |
Function
[PSPF_ECOLI] Transcriptional activator for the phage shock protein (psp) operon (pspABCDE) and pspG gene.[1] [2] [3]
Publication Abstract from PubMed
Binding and hydrolysis of ATP is universally required by AAA+ proteins to underpin their mechano-chemical work. Here we explore the roles of the ATPase site in an AAA+ transcriptional activator protein, the phage shock protein F (PspF), by specifically altering the Walker B motif sequence required in catalyzing ATP hydrolysis. One such mutant, the E108Q variant, is defective in ATP hydrolysis but fully remodels target transcription complexes, the RNAP-sigma54 holoenzyme, in an ATP dependent manner. Structural analysis of the E108Q variant reveals that unlike wild-type protein, which has distinct conformations for E108 residue in the ATP and ADP bound forms, E108Q adapts the same conformation irrespective of nucleotide bound. Our data show that the remodeling activities of E108Q are strongly favored on pre-melted DNA and engagement with RNAP-sigma54 using ATP binding can be sufficient to convert the inactive holoenzyme to an active form, while hydrolysis per se is required for nucleic acid remodeling that leads to transcription bubble formation. Furthermore, using linked dimer constructs, we show that RNAP-sigma54 engagement by adjacent subunits within a hexamer are required for this protein remodeling activity while DNA remodeling activity can tolerate defective ATP hydrolysis of alternating subunits.
Molecular basis of nucleotide-dependent substrate engagement and remodeling by an AAA+ activator.,Darbari VC, Lawton E, Lu D, Burrows PC, Wiesler S, Joly N, Zhang N, Zhang X, Buck M Nucleic Acids Res. 2014 Jul 25. pii: gku588. PMID:25063294[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Jovanovic G, Weiner L, Model P. Identification, nucleotide sequence, and characterization of PspF, the transcriptional activator of the Escherichia coli stress-induced psp operon. J Bacteriol. 1996 Apr;178(7):1936-45. PMID:8606168
- ↑ Lloyd LJ, Jones SE, Jovanovic G, Gyaneshwar P, Rolfe MD, Thompson A, Hinton JC, Buck M. Identification of a new member of the phage shock protein response in Escherichia coli, the phage shock protein G (PspG). J Biol Chem. 2004 Dec 31;279(53):55707-14. Epub 2004 Oct 13. PMID:15485810 doi:10.1074/jbc.M408994200
- ↑ Joly N, Burrows PC, Engl C, Jovanovic G, Buck M. A lower-order oligomer form of phage shock protein A (PspA) stably associates with the hexameric AAA(+) transcription activator protein PspF for negative regulation. J Mol Biol. 2009 Dec 11;394(4):764-75. doi: 10.1016/j.jmb.2009.09.055. Epub 2009 , Oct 3. PMID:19804784 doi:10.1016/j.jmb.2009.09.055
- ↑ Darbari VC, Lawton E, Lu D, Burrows PC, Wiesler S, Joly N, Zhang N, Zhang X, Buck M. Molecular basis of nucleotide-dependent substrate engagement and remodeling by an AAA+ activator. Nucleic Acids Res. 2014 Jul 25. pii: gku588. PMID:25063294 doi:http://dx.doi.org/10.1093/nar/gku588
|
