PDBsum entry 4do2

RNA binding protein

PDB id: 4do2

Contents

Protein chains

57 a.a.

Waters ×169

PDB id:

4do2

Name:

RNA binding protein

Title:

Crystal structure of the rop protein mutant d30p/a31g at resolution 1.4 resolution.

Structure:

Regulatory protein rop. Chain: a, b. Synonym: RNA one modulator, rom. Engineered: yes. Mutation: yes

Source:

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

Resolution:

1.40Å R-factor: 0.160 R-free: 0.188

Authors:

M.Amprazi,E.G.Kapetaniou,M.Kokkinidis

Key ref:

M.Amprazi et al. (2014). Structural plasticity of 4-α-helical bundles exemplified by the puzzle-like molecular assembly of the Rop protein. Proc Natl Acad Sci U S A, 111, 11049-11054. PubMed id: 25024213 DOI: 10.1073/pnas.1322065111

Date:

09-Feb-12 Release date: 13-Feb-13

Protein chains

P03051  (ROP_ECOLX) -  Regulatory protein rop from Escherichia coli

Seq: 63 a.a.

Struc: 57 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

DOI no: 10.1073/pnas.1322065111

Proc Natl Acad Sci U S A 111:11049-11054 (2014)

PubMed id: 25024213

Structural plasticity of 4-α-helical bundles exemplified by the puzzle-like molecular assembly of the Rop protein.

M.Amprazi, D.Kotsifaki, M.Providaki, E.G.Kapetaniou, G.Fellas, I.Kyriazidis, J.Pérez, M.Kokkinidis.

ABSTRACT

The dimeric Repressor of Primer (Rop) protein, a widely used model system for the study of coiled-coil 4-α-helical bundles, is characterized by a remarkable structural plasticity. Loop region mutations lead to a wide range of topologies, folding states, and altered physicochemical properties. A protein-folding study of Rop and several loop variants has identified specific residues and sequences that are linked to the observed structural plasticity. Apart from the native state, native-like and molten-globule states have been identified; these states are sensitive to reducing agents due to the formation of nonnative disulfide bridges. Pro residues in the loop are critical for the establishment of new topologies and molten globule states; their effects, however, can be in part compensated by Gly residues. The extreme plasticity in the assembly of 4-α-helical bundles reflects the capacity of the Rop sequence to combine a specific set of hydrophobic residues into strikingly different hydrophobic cores. These cores include highly hydrated ones that are consistent with the formation of interchain, nonnative disulfide bridges and the establishment of molten globules. Potential applications of this structural plasticity are among others in the engineering of bio-inspired materials.