Evidence map›Paper›PMID 28506526›Full record

ArticleBiophysical journal2017

Molecular Simulation and Biochemical Studies Support an Elevator-type Transport Mechanism in EIIC.

Jumin Lee, Zhenning Ren, Ming Zhou, Wonpil Im

Abstract readLetter
In one paragraph

Article in Biophysical journal, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
–field-weighted citation impact
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

3 citing papers in PubMed.

  1. Article
  2. Article
  3. Structure of an EIIC sugar transporter trapped in an inward-facing conformation.Proceedings of the National Academy of Sciences of the United States of America · 2018
    Article
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

4 authors.

Jumin LeeDepartment of Biological Sciences and Bioengineering Program, Lehigh University, Bethlehem, Pennsylvania.
Zhenning RenVerna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas.
Ming ZhouVerna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas. Electronic address: mzhou@bcm.edu.
Wonpil ImDepartment of Biological Sciences and Bioengineering Program, Lehigh University, Bethlehem, Pennsylvania. Electronic address: wonpil@lehigh.edu.

Funding

Synthetic Antigen Binder CoreU54GM087519 · NIGMS · UNIVERSITY OF CHICAGO · PI BEZANILLA, FRANCISCO J · 2010 to 2017
$31.9M
Structural mechanism of K channel modulation by cellular redox stateR01HL086392 · NHLBI · COLUMBIA UNIVERSITY HEALTH SCIENCES · PI ZHOU, MING · 2006 to 2018
$3.9M
Structure and function of urea transportersR01DK088057 · NIDDK · COLUMBIA UNIVERSITY HEALTH SCIENCES · PI ZHOU, MING · 2010 to 2014
$1.7M
Structure and Function of a Phosphorylation Coupled Saccharide TransporterR01GM098878 · NIGMS · COLUMBIA UNIVERSITY HEALTH SCIENCES · PI ZHOU, MING · 2011 to 2014
$1.2M
NHLBI NIH HHS R01 HL086392NIDDK NIH HHS R01 DK088057NIGMS NIH HHS R01 GM098878NIGMS NIH HHS U54 GM087519
6 · The paper itself

Abstract

Enzyme IIC (EIIC) is a membrane-embedded sugar transport protein that is part of the phosphoenolpyruvate-dependent phosphotransferases. Crystal structures of two members of the glucose EIIC superfamily, bcChbC in the inward-facing conformation and bcMalT in the outward-facing conformation, were previously solved. Comparing the two structures led us to the hypothesis that sugar translocation could be achieved by an elevator-type transport mechanism in which a transport domain binds to the substrate and, through rigid body motions, transports it across the membrane. To test this hypothesis and to obtain more accurate descriptions of alternate conformations of the two proteins, we first performed collective variable-based steered molecular dynamics (CVSMD) simulations starting with the two crystal structures embedded in model lipid bilayers, and steered their transport domain toward their own alternative conformation. Our simulations show that large rigid-body motions of the transport domain (55° in rotation and 8 Å in translation) lead to access of the substrate binding site to the alternate side of the membrane. H-bonding interactions between the sugar and the protein are intact, although the side chains of the binding-site residues were not restrained in the simulation. Pairs of residues in bcMalT that are far apart in the crystal structure become close to each other in the simulated model. Some of these pairs can be cross-linked by a mercury ion when mutated to cysteines, providing further support for the CVSMD-generated model. In addition, bcMalT binds to maltose with similar affinities before and after the cross-linking, suggesting that the binding site is preserved after the conformational change. In combination, these results support an elevator-type transport mechanism in EIIC.

Indexed as

Bacillus cereusBinding SitesHydrogen BondingLipid BilayersMaltoseMembrane Transport ProteinsMolecular Dynamics SimulationMutationPhosphatidylethanolaminesPhosphatidylglycerolsPhosphoenolpyruvate Sugar Phosphotransferase System1-palmitoyl-2-oleoylglycero-3-phosphoglycerol1-palmitoyl-2-oleoylphosphatidylethanolamineChbC protein, Borrelia burgdorferiLipid BilayersMaltoseMembrane Transport ProteinsPhosphatidylethanolaminesPhosphatidylglycerolsPhosphoenolpyruvate Sugar Phosphotransferase System

Identifiers

PMID28506526
PMCPMC5474738

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.