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| Status |
Public on Jul 01, 2014 |
| Title |
Genome-wide transcriptome analysis of the oxygen response of L. johnsonii reveals that NADH oxidase is a secondary H2O2 source. |
| Organism |
Lactobacillus johnsonii |
| Experiment type |
Expression profiling by array
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| Summary |
Oxidative stress due to endogenous hydrogen peroxide production by Lactobacillus species is a well-known issue in the food industry. In this study, the transcriptional response to oxygen of Lactobacillus johnsonii, one of the H2O2-producing strains used in the food industry, was analyzed. It was found that aerobic growth conditions led to a more than two-fold downregulation of 45 genes as compared to anaerobic growth, whereas 6 genes were more than twofold upregulated. Among the upregulated genes were two genes that displayed significant homology to NADH-dependent oxidoreductase (NOX). The postulated transcriptional regulation of the nox promoter by oxygen was studied using a GUS-reporter construct, confirming a 2.1-fold upregulated GUS-expression upon aerobic growth. Exposure to sublethal levels of hydrogen peroxide did not result in significant regulation of the nox promoter. In a previous study of hydrogen peroxide production by L. johnsonii, a NADH flavin reductase (NFR) was identified to be involved in hydrogen peroxide production. An NFR-deficient derivative was strongly impaired in H2O2 production, but regained a partial H2O2 producing capacity upon prolonged oxygen exposure. The nox-promoter appeared to be 3.6-fold upregulated under aerobic conditions in the NFR-deficient background, which may imply a role of this gene in the regained H2O2 production. Indeed, deletion of the nox-gene in the NFR-deletion background, resulted in a strain that no longer produced H2O2, also during prolonged exposure to oxygen. The double-mutant (nfr, nox) displayed strongly impaired aerobic growth and oxygenation induced rapid growth stagnation that is not caused by H2O2. We conclude that H2O2 production in L. johnsonii is primarily dependent on NFR but can also involve an oxygen-inducible NADH oxidase under aerobic conditions. Moreover, our results imply that H2O2 production plays a prominent role in oxygen tolerance of L. johnsonii.
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| Overall design |
loop design of the samples including two shortcuts
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| Contributor(s) |
Hertzberger R, Starrenburg M, van Swam I, Wels M, Pridmore RD, Gysler C, de Mattos MJ, Kleerebezem M |
| Citation missing |
Has this study been published? Please login to update or notify GEO. |
| Submission date |
Dec 02, 2013 |
| Last update date |
Jul 02, 2014 |
| Contact name |
Michiel Wels |
| E-mail(s) |
michiel.wels@nizo.com
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| Organization name |
NIZO food research
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| Street address |
Kernhemseweg 2
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| City |
Ede |
| ZIP/Postal code |
6718 ZB |
| Country |
Netherlands |
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| Platforms (1) |
| GPL18009 |
Lactobacillus johnsonii LA-1 44K 60-mer array, Version 2 |
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| Samples (12)
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| GSM1277381 |
anaerobic logarithmic culture (1.3) / aerobic logarithmic culture (O 1.3) 1st of duplicate comparison |
| GSM1277382 |
30 min after onset CO2 depletion (2.3) vs CO2 supplemented culture (1.3) 1st of duplicate time series |
| GSM1277383 |
60 min after onset CO2 depletion (3.3) vs 30 min after onset CO2 depletion (2.3) 1st of duplicate time series |
| GSM1277384 |
120 min after onset CO2 depletion (4.3) vs 60 min after onset CO2 depletion (3.3) 1st of duplicate time series |
| GSM1277385 |
duplicate 120 min after onset CO2 depletion |
| GSM1277386 |
60 min after onset CO2 depletion (3.4) vs 120 min after onset CO2 depletion (4.4) 2nd of duplicate time series |
| GSM1277387 |
30 min after onset CO2 depletion (2.4) vs 60 min after onset CO2 depletion (3.4) 2nd of duplicate time series |
| GSM1277388 |
CO2 supplemented logarithmic culture (1.4) vs 30 min after onset CO2 depletion (2.4) 2nd of duplicate time series |
| GSM1277389 |
aerobic logarithmic culture (O1.4) vs anaerobic logarithmic culture (1.4) 2nd of duplicate comparison |
| GSM1277390 |
duplicate of aerobic logarithmic culture |
| GSM1277391 |
30m after CO2 depletion in 1st duplicate time series (2.3) vs CO2 supplemented (1.4) in 2nd duplicate time series |
| GSM1277392 |
60m after CO2 depletion in 1st duplicate time series (3.3) vs 30m after CO2 depletion in 2nd duplicate time series |
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| Relations |
| BioProject |
PRJNA230384 |
| Supplementary file |
Size |
Download |
File type/resource |
| GSE52876_RAW.tar |
13.4 Mb |
(http)(custom) |
TAR (of TXT) |
| Processed data included within Sample table |
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