Evidence map›Paper›PMID 24520888›Full record

ArticleBiochemistry2014

Galactoside-binding site in LacY.

Xiaoxu Jiang, Maria Katerina R Villafuerte, Magnus Andersson, Stephen H White, H Ronald Kaback

Open access · bronzeAbstract read
In one paragraph

Article in Biochemistry, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers.

0numbers the graph read from it
0cells of the map it votes in
7citing papers in PubMed
1.3field-weighted citation impact, top 20% 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

7 citing papers in PubMed, 13 citations in OpenAlex.

  1. Article
  2. Article
  3. Article
  4. Review
  5. Structure of LacY with an α-substituted galactoside: Connecting the binding site to the protonation site.Proceedings of the National Academy of Sciences of the United States of America · 2015
    Article
  6. A chemiosmotic mechanism of symport.Proceedings of the National Academy of Sciences of the United States of America · 2015
    Article
  7. Structure of sugar-bound LacY.Proceedings of the National Academy of Sciences of the United States of America · 2014
    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

5 authors at 2 institutions in 1 country.

Xiaoxu JiangDepartment of Physiology and Department of Microbiology, Immunology and Molecular Genetics, Molecular Biology Institute, University of California at Los Angeles , Los Angeles, California 90095-7327, United States.
Maria Katerina R Villafuerte
Magnus Andersson
Stephen H White
H Ronald Kaback
University of California, Los Angeles · USUniversity of California, Irvine · US

Funding

Yeast ExpressionP50GM073210 · NIGMS · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI STROUD, ROBERT M · 2004 to 2013
$21.5M
SPECIALIZED CENTER FOR THE PROTEIN STRUCTURE INITIATIVEU54GM074929 · NIGMS · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI STAHLBERG, HENNING · 2005 to 2009
$16.6M
Project 3: Structural Studies of Voltage-Gated Potassium Channels as FunctionP01GM086685 · NIGMS · UNIVERSITY OF CALIFORNIA-IRVINE · PI WORCESTER, DAVID · 2009 to 2013
$6.7M
NEW APPROACHES TO MEMBRANE PROTEIN STRUCTURESR01DK051131 · NIDDK · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI KABACK, HOWARD RONALD · 1996 to 2014
$5.2M
Membrane Protein Folding and AssemblyR01GM074637 · NIGMS · UNIVERSITY OF CALIFORNIA-IRVINE · PI WHITE, STEPHEN H. · 2006 to 2020
$4.5M
Structural Basis for Mechanism of Secondary TransportersR01DK069463 · NIDDK · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI KABACK, HOWARD RONALD · 2005 to 2013
$3.7M
Structural Basis for Mechanism of Secondary TransportersR56DK069463 · NIDDK · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI KABACK, HOWARD RONALD · 2009 to 2009
$500k
Dynamics of the Lactose Permease of Escherichia ColiR56DK051131 · NIDDK · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI KABACK, HOWARD RONALD · 2015 to 2015
$154k
NIDDK NIH HHS DK051131NIDDK NIH HHS DK069463NIGMS NIH HHS GM073210NIGMS NIH HHS GM074637NIGMS NIH HHS GM074929NIGMS NIH HHS GM086685
6 · The paper itself

Abstract

Although an X-ray crystal structure of lactose permease (LacY) has been presented with bound galactopyranoside, neither the sugar nor the residues ligating the sugar can be identified with precision at ~3.5 Å. Therefore, additional evidence is important for identifying side chains likely to be involved in binding. On the basis of a clue from site-directed alkylation suggesting that Asn272, Gly268, and Val264 on one face of helix VIII might participate in galactoside binding, molecular dynamics simulations were conducted initially. The simulations indicate that Asn272 (helix VIII) is sufficiently close to the galactopyranosyl ring of a docked lactose analogue to play an important role in binding, the backbone at Gly268 may be involved, and Val264 does not interact with the bound sugar. When the three side chains are subjected to site-directed mutagenesis, with the sole exception of mutant Asn272 → Gln, various other replacements for Asn272 either markedly decrease affinity for the substrate (i.e., high KD) or abolish binding altogether. However, mutant Gly268 → Ala exhibits a moderate 8-fold decrease in affinity, and binding by mutant Val264 → Ala is affected only minimally. Thus, Asn272 and possibly Gly268 may comprise additional components of the galactoside-binding site in LacY.

Indexed as

Binding SitesEscherichia coli ProteinsGalactosidesMonosaccharide Transport ProteinsProtein Structure, SecondarySymportersEscherichia coli ProteinsGalactosidesLacY protein, E coliMonosaccharide Transport ProteinsSymporters

Identifiers

PMID24520888
PMCPMC3985706
OpenAlexW2139560006

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

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.