Evidence map›Paper›PMID 25954892›Full record

ArticleBiophysical journal2015

The folding unit of phosphofructokinase-2 as defined by the biophysical properties of a monomeric mutant.

César A Ramírez-Sarmiento, Mauricio Baez, Ricardo A Zamora, Deepa Balasubramaniam, Jorge Babul, Elizabeth A Komives, Victoria Guixé

Open access · bronzeAbstract read
In one paragraph

Article in Biophysical journal, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
0.7field-weighted citation impact, top 32% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed, 8 citations in OpenAlex.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 2 institutions in 2 countries.

César A Ramírez-SarmientoDepartamento de Biología, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile.
Mauricio BaezDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Casilla 233, Santiago, Chile.
Ricardo A ZamoraDepartamento de Biología, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile.
Deepa BalasubramaniamDepartment of Chemistry and Biochemistry, University of California San Diego, La Jolla, California.
Jorge BabulDepartamento de Biología, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile.
Elizabeth A KomivesDepartment of Chemistry and Biochemistry, University of California San Diego, La Jolla, California. Electronic address: ekomives@ucsd.edu.
Victoria GuixéDepartamento de Biología, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile. Electronic address: vguixe@uchile.cl.
University of Chile · CLUniversity of California, San Diego · US

Funding

Synapt G2-S System with HXMS AutomationS10OD016234 · OD · UNIVERSITY OF CALIFORNIA, SAN DIEGO · PI KOMIVES, ELIZABETH A. · 2013 to 2013
$600k
NIH HHS 1S10OD016234NIH HHS S10 OD016234
6 · The paper itself

Abstract

Escherichia coli phosphofructokinase-2 (Pfk-2) is an obligate homodimer that follows a highly cooperative three-state folding mechanism N2 ↔ 2I ↔ 2U. The strong coupling between dissociation and unfolding is a consequence of the structural features of its interface: a bimolecular domain formed by intertwining of the small domain of each subunit into a flattened β-barrel. Although isolated monomers of E. coli Pfk-2 have been observed by modification of the environment (changes in temperature, addition of chaotropic agents), no isolated subunits in native conditions have been obtained. Based on in silico estimations of the change in free energy and the local energetic frustration upon binding, we engineered a single-point mutant to destabilize the interface of Pfk-2. This mutant, L93A, is an inactive monomer at protein concentrations below 30 μM, as determined by analytical ultracentrifugation, dynamic light scattering, size exclusion chromatography, small-angle x-ray scattering, and enzyme kinetics. Active dimer formation can be induced by increasing the protein concentration and by addition of its substrate fructose-6-phosphate. Chemical and thermal unfolding of the L93A monomer followed by circular dichroism and dynamic light scattering suggest that it unfolds noncooperatively and that the isolated subunit is partially unstructured and marginally stable. The detailed structural features of the L93A monomer and the F6P-induced dimer were ascertained by high-resolution hydrogen/deuterium exchange mass spectrometry. Our results show that the isolated subunit has overall higher solvent accessibility than the native dimer, with the exception of residues 240-309. These residues correspond to most of the β-meander module and show the same extent of deuterium uptake as the native dimer. Our results support the idea that the hydrophobic core of the isolated monomer of Pfk-2 is solvent-penetrated in native conditions and that the β-meander module is not affected by monomerizing mutations.

Indexed as

Protein FoldingProtein MultimerizationAmino Acid SequenceEscherichia coliEscherichia coli ProteinsMolecular Sequence DataMutationPhosphofructokinase-2Protein Structure, TertiaryProtein SubunitsEscherichia coli ProteinsPhosphofructokinase-2Protein Subunits

Identifiers

PMID25954892
PMCPMC4423062
OpenAlexW2097552312

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.