Evidence map›Paper›PMID 10482511›Full record

ArticleJournal of bacteriology1999

Role of the alkyl hydroperoxide reductase (ahpCF) gene in oxidative stress defense of the obligate Anaerobe bacteroides fragilis.

E R Rocha, C J Smith

Open access · bronzeAbstract readComparative Study
In one paragraph

Article in Journal of bacteriology, 1999. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 47 papers.

0numbers the graph read from it
0cells of the map it votes in
47citing papers in PubMed
3.3field-weighted citation impact, top 8% 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

47 citing papers in PubMed, 109 citations in OpenAlex.

  1. Article
  2. Hydrocarbon degradation and genomic insights ofFrontiers in microbiology · 2026
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  3. Transcription regulator TrtA modulates oxygen stress response inApplied and environmental microbiology · 2025
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  12. Article
  13. Transcriptomic Responses ofFrontiers in cellular and infection microbiology · 2022
    Article
  14. Relevance of peroxiredoxins in pathogenic microorganisms.Applied microbiology and biotechnology · 2021
    Review
  15. TheInfection and immunity · 2020
    Article
  16. Article
  17. Article
  18. Article
  19. Article
  20. Factors Mediating Environmental Biofilm Formation byFrontiers in cellular and infection microbiology · 2018
    Review
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

2 authors at 1 institution in 1 country.

E R RochaDepartment of Microbiology and Immunology, School of Medicine, East Carolina University, Greenville, North Carolina, USA. rocha@brody.med.ecu.edu
C J Smith
East Carolina University · US

Funding

ROLE OF B.FRAGILIS OXYGEN STRESS RESPONSE IN INFECTIONR01AI040588 · NIAID · EAST CAROLINA UNIVERSITY · PI SMITH, CHARLES J. · 1999 to 2014
$3.5M
ROLE OF B.FRAGILIS OXYGEN STRESS RESPONSE IN INFECTIONR56AI040588 · NIAID · EAST CAROLINA UNIVERSITY · PI ROCHA, EDSON R, SMITH, CHARLES J. · 2009 to 2009
$334k
NIAID NIH HHS AI40588NIAID NIH HHS R01 AI040588NIAID NIH HHS R56 AI040588
6 · The paper itself

Abstract

In this study we report the identification and role of the alkyl hydroperoxide reductase (ahp) gene in Bacteroides fragilis. The two components of ahp, ahpC, and ahpF, are organized in an operon, and the deduced amino acid sequences revealed that B. fragilis AhpCF shares approximately 60% identity to orthologues in other gram-positive and gram-negative bacteria. Northern blot hybridization analysis of total RNA showed that the ahpCF genes were transcribed as a polycistronic 2.4-kb mRNA and that ahpC also was present as a 0.6-kb monocistronic mRNA. ahpC and ahpCF mRNAs were induced approximately 60-fold following H(2)O(2) treatment or oxygen exposure of the parent strain but were constitutive in a peroxide-resistant strain. Further investigation using an ahpCF'::beta-xylosidase gene transcriptional fusion confirmed that ahpCF had lost normal regulation in the peroxide-resistant strain compared to the parent. The ahpCF mutant was more sensitive to growth inhibition and mutagenesis by organic peroxides than the parent strain, as determined by disk inhibition assays and the frequency of mutation to fusidic acid resistance. This finding suggests that the ahp genes play an important role in peroxide resistance in B. fragilis. Under anaerobic conditions, we observed increases in the number of spontaneous fusidic acid-resistant mutants of five- and sevenfold in ahpCF and ahpF strain backgrounds, respectively, and eightfold in the ahpCF katB double mutant strain compared to the parent and katB strains. In addition, ahpCF, ahpF, and ahpCF katB mutants were slightly more sensitive to oxygen exposure than the parent strain. Moreover, the isolation of a strain with enhanced aerotolerance and high-level resistance to alkyl hydroperoxides from an ahpCF katB parent suggests that the physiological responses to peroxide toxicity and to the toxic effects of molecular oxygen are overlapping and complex in this obligate anaerobe.

Indexed as

Gene Expression Regulation, BacterialOperonOxidative StressPeroxidasesTranscription, GeneticAmino Acid SequenceAnaerobiosisBacteroides fragilisBase SequenceCloning, MolecularEscherichia coliEscherichia coli ProteinsGene Expression Regulation, EnzymologicHydrogen PeroxideMolecular Sequence DataMutagenesis, Site-DirectedahpC protein, E coliahpF protein, E coliEscherichia coli ProteinsHydrogen PeroxideOxidoreductasesPeroxidasesPeroxiredoxinsRecombinant ProteinsRNA, Messenger

Identifiers

PMID10482511
PMCPMC94090
OpenAlexW2095812966

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.