Evidence map›Paper›PMID 26431966›Full record

ArticleApplied and environmental microbiology2015

Two pathways for glutamate biosynthesis in the syntrophic bacterium Syntrophus aciditrophicus.

Marie Kim, Huynh M Le, Xiulan Xie, Xueyang Feng, Yinjie J Tang, Housna Mouttaki, Michael J McInerney, Wolfgang Buckel

Open access · bronzeAbstract read
In one paragraph

Article in Applied and environmental microbiology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
0.6field-weighted citation impact, top 30% 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

1 citing paper in PubMed, 7 citations in OpenAlex.

  1. 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

8 authors at 3 institutions in 2 countries.

Marie KimMax-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany Fachbereich Biologie and Synmikro, Philipps-Universität, Marburg, Germany.
Huynh M LeDepartment of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
Xiulan XieFachbereich Chemie, Philipps-Universität, Marburg, Germany.
Xueyang FengEnergy, Environmental and Chemical Engineering Department, Washington University, St. Louis, Missouri, USA.
Yinjie J TangEnergy, Environmental and Chemical Engineering Department, Washington University, St. Louis, Missouri, USA.
Housna MouttakiDepartment of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
Michael J McInerneyDepartment of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
Wolfgang BuckelMax-Planck-Institut für terrestrische Mikrobiologie, Marburg, Germany Fachbereich Biologie and Synmikro, Philipps-Universität, Marburg, Germany buckel@staff.uni-marburg.de.
Philipps University of Marburg · DEUniversity of Oklahoma · USWashington University in St. Louis · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The anaerobic metabolism of crotonate, benzoate, and cyclohexane carboxylate by Syntrophus aciditrophicus grown syntrophically with Methanospirillum hungatei provides a model to study syntrophic cooperation. Recent studies revealed that S. aciditrophicus contains Re-citrate synthase but lacks the common Si-citrate synthase. To establish whether the Re-citrate synthase is involved in glutamate synthesis via the oxidative branch of the Krebs cycle, we have used [1-(13)C]acetate and [1-(14)C]acetate as well as [(13)C]bicarbonate as additional carbon sources during axenic growth of S. aciditrophicus on crotonate. Our analyses showed that labeled carbons were detected in at least 14 amino acids, indicating the global utilization of acetate and bicarbonate. The labeling patterns of alanine and aspartate verified that pyruvate and oxaloacetate were synthesized by consecutive carboxylations of acetyl coenzyme A (acetyl-CoA). The isotopomer profile and (13)C nuclear magnetic resonance (NMR) spectroscopy of the obtained [(13)C]glutamate, as well as decarboxylation of [(14)C]glutamate, revealed that this amino acid was synthesized by two pathways. Unexpectedly, only the minor route used Re-citrate synthase (30 to 40%), whereas the majority of glutamate was synthesized via the reductive carboxylation of succinate. This symmetrical intermediate could have been formed from two acetates via hydration of crotonyl-CoA to 4-hydroxybutyryl-CoA. 4-Hydroxybutyrate was detected in the medium of S. aciditrophicus when grown on crotonate, but an active hydratase could not be measured in cell extracts, and the annotated 4-hydroxybutyryl-CoA dehydratase (SYN_02445) lacks key amino acids needed to catalyze the hydration of crotonyl-CoA. Besides Clostridium kluyveri, this study reveals the second example of a microbial species to employ two pathways for glutamate synthesis.

Indexed as

AcetatesAcetyl Coenzyme AAcyl Coenzyme ACitrate (si)-SynthaseDeltaproteobacteriaGlutamic AcidHydro-LyasesHydroxybutyratesMagnetic Resonance SpectroscopyMetabolic Networks and PathwaysMethanospirillumMicrobial InteractionsOxidation-ReductionSuccinic Acid4-hydroxybutyric acid4-hydroxybutyryl-CoA dehydratase4-hydroxybutyryl-coenzyme AAcetatesAcetyl Coenzyme AAcyl Coenzyme ACitrate (si)-Synthasecrotonyl-coenzyme AGlutamic AcidHydro-LyasesHydroxybutyratesSuccinic Acid

Identifiers

PMID26431966
PMCPMC4644651
OpenAlexW2252924420

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.