PDBsum entry 2bjv

Transcription

PDB id: 2bjv

Contents

Protein chain

237 a.a. *

Waters ×162

* Residue conservation analysis

PDB id:

2bjv

Name:

Transcription

Title:

Crystal structure of pspf(1-275) r168a mutant

Structure:

Psp operon transcriptional activator. Chain: a. Fragment: aaa domain, residues 1-265. Synonym: pspf, phage shock protein f. Engineered: yes. Mutation: yes

Source:

Escherichia coli. Organism_taxid: 562. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

1.70Å R-factor: 0.172 R-free: 0.212

Authors:

M.Rappas,J.Schumacher,F.Beuron,H.Niwa,P.Bordes,S.Wigneshweraraj, C.A.Keetch,C.V.Robinson,M.Buck,X.Zhang

Key ref:

M.Rappas et al. (2005). Structural insights into the activity of enhancer-binding proteins. Science, 307, 1972-1975. PubMed id: 15790859 DOI: 10.1126/science.1105932

Date:

08-Feb-05 Release date: 31-Mar-05

Protein chain

P37344  (PSPF_ECOLI) -  Psp operon transcriptional activator from Escherichia coli (strain K12)

Seq: 325 a.a.

Struc: 237 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1126/science.1105932

Science 307:1972-1975 (2005)

PubMed id: 15790859

Structural insights into the activity of enhancer-binding proteins.

M.Rappas, J.Schumacher, F.Beuron, H.Niwa, P.Bordes, S.Wigneshweraraj, C.A.Keetch, C.V.Robinson, M.Buck, X.Zhang.

ABSTRACT

Activators of bacterial sigma54-RNA polymerase holoenzyme are mechanochemical proteins that use adenosine triphosphate (ATP) hydrolysis to activate transcription. We have determined by cryogenic electron microscopy (cryo-EM) a 20 angstrom resolution structure of an activator, phage shock protein F [PspF(1-275)], which is bound to an ATP transition state analog in complex with its basal factor, sigma54. By fitting the crystal structure of PspF(1-275) at 1.75 angstroms into the EM map, we identified two loops involved in binding sigma54. Comparing enhancer-binding structures in different nucleotide states and mutational analysis led us to propose nucleotide-dependent conformational changes that free the loops for association with sigma54.

Selected figure(s)

Figure 2.
Fig. 2. Crystal structure of PspF[(1-275)]. The P6[5] hexamer of PspF[(1-275)] is shown as viewed down the sixfold axis. Both /ß (green) and -helical domains (pink) of one monomer are contoured with dashed lines. The nucleotide-binding pocket is highlighted in yellow and is located in the cleft between the /ß and -helical domain at the interface with the adjacent monomer. N- and C-termini of two adjacent monomers are also shown. Color coding is as follows: blue, helices; red, central ß sheet; orange, L1; and green, L2. The tip of the highlighted L1 is shown as a dotted line because residues 82 to 89 were not resolved in our crystal structure.

Figure 3.
Fig. 3. Fitting of the PspF[(1-275)] crystal structure into the EM electron density map of the PspF[(1-275)]-ADP.AlF[x]- 54 complex. (A) The front view of the EM density is colored transparent gray and the PspF[(1-275)] crystal structure has a blue ribbon representation. The fitting of the -helical domain into one "claw" of the hexameric ring is highlighted; the densities connecting PspF[(1-275)] to 54 are indicated by red arrows. (B) Cross-eye stereo view of the fitting of one pair of L1 and L2 loops into the connecting densities; the tip of L1 is shown as a dotted line because residues 82 to 89 are not resolved. When positioned in the densities, the loops extend upward almost at a right angle to the plane of the hexamer.

The above figures are reprinted by permission from the AAAs: Science (2005, 307, 1972-1975) copyright 2005.

Figures were selected by an automated process.