Contextual Flexibility in <named-content content-type="genus-species">Pseudomonas aeruginosa</named-content> Central Carbon Metabolism during Growth in Single Carbon Sources
ABSTRACT Pseudomonas aeruginosa is an opportunistic human pathogen, particularly noted for causing infections in the lungs of people with cystic fibrosis (CF). Previous studies have shown that the gene expression profile of P. aeruginosa appears to converge toward a common metabolic program as the o...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
American Society for Microbiology
2020-04-01
|
| Series: | mBio |
| Subjects: | |
| Online Access: | https://journals.asm.org/doi/10.1128/mBio.02684-19 |
| _version_ | 1818434473488809984 |
|---|---|
| author | Stephen K. Dolan Michael Kohlstedt Stephen Trigg Pedro Vallejo Ramirez Clemens F. Kaminski Christoph Wittmann Martin Welch |
| author_facet | Stephen K. Dolan Michael Kohlstedt Stephen Trigg Pedro Vallejo Ramirez Clemens F. Kaminski Christoph Wittmann Martin Welch |
| author_sort | Stephen K. Dolan |
| collection | DOAJ |
| description | ABSTRACT Pseudomonas aeruginosa is an opportunistic human pathogen, particularly noted for causing infections in the lungs of people with cystic fibrosis (CF). Previous studies have shown that the gene expression profile of P. aeruginosa appears to converge toward a common metabolic program as the organism adapts to the CF airway environment. However, we still have only a limited understanding of how these transcriptional changes impact metabolic flux at the systems level. To address this, we analyzed the transcriptome, proteome, and fluxome of P. aeruginosa grown on glycerol or acetate. These carbon sources were chosen because they are the primary breakdown products of an airway surfactant, phosphatidylcholine, which is known to be a major carbon source for P. aeruginosa in CF airways. We show that the fluxes of carbon throughout central metabolism are radically different among carbon sources. For example, the newly recognized “EDEMP cycle” (which incorporates elements of the Entner-Doudoroff [ED] pathway, the Embden-Meyerhof-Parnas [EMP] pathway, and the pentose phosphate [PP] pathway) plays an important role in supplying NADPH during growth on glycerol. In contrast, the EDEMP cycle is attenuated during growth on acetate, and instead, NADPH is primarily supplied by the reaction catalyzed by isocitrate dehydrogenase(s). Perhaps more importantly, our proteomic and transcriptomic analyses revealed a global remodeling of gene expression during growth on the different carbon sources, with unanticipated impacts on aerobic denitrification, electron transport chain architecture, and the redox economy of the cell. Collectively, these data highlight the remarkable metabolic plasticity of P. aeruginosa; that plasticity allows the organism to seamlessly segue between different carbon sources, maximizing the energetic yield from each. IMPORTANCE Pseudomonas aeruginosa is an opportunistic human pathogen that is well known for causing infections in the airways of people with cystic fibrosis. Although it is clear that P. aeruginosa is metabolically well adapted to life in the CF lung, little is currently known about how the organism metabolizes the nutrients available in the airways. In this work, we used a combination of gene expression and isotope tracer (“fluxomic”) analyses to find out exactly where the input carbon goes during growth on two CF-relevant carbon sources, acetate and glycerol (derived from the breakdown of lung surfactant). We found that carbon is routed (“fluxed”) through very different pathways during growth on these substrates and that this is accompanied by an unexpected remodeling of the cell’s electron transfer pathways. Having access to this “blueprint” is important because the metabolism of P. aeruginosa is increasingly being recognized as a target for the development of much-needed antimicrobial agents. |
| first_indexed | 2024-12-14T16:37:33Z |
| format | Article |
| id | doaj.art-2ddf3bc86caa447c8bf3811811603985 |
| institution | Directory Open Access Journal |
| issn | 2150-7511 |
| language | English |
| last_indexed | 2024-12-14T16:37:33Z |
| publishDate | 2020-04-01 |
| publisher | American Society for Microbiology |
| record_format | Article |
| series | mBio |
| spelling | doaj.art-2ddf3bc86caa447c8bf38118116039852022-12-21T22:54:24ZengAmerican Society for MicrobiologymBio2150-75112020-04-0111210.1128/mBio.02684-19Contextual Flexibility in <named-content content-type="genus-species">Pseudomonas aeruginosa</named-content> Central Carbon Metabolism during Growth in Single Carbon SourcesStephen K. Dolan0Michael Kohlstedt1Stephen Trigg2Pedro Vallejo Ramirez3Clemens F. Kaminski4Christoph Wittmann5Martin Welch6Department of Biochemistry, University of Cambridge, Cambridge, United KingdomInstitute for Systems Biotechnology, Saarland University, Saarbrücken, GermanyDepartment of Biochemistry, University of Cambridge, Cambridge, United KingdomDepartment of Chemical Engineering, University of Cambridge, Cambridge, United KingdomDepartment of Chemical Engineering, University of Cambridge, Cambridge, United KingdomInstitute for Systems Biotechnology, Saarland University, Saarbrücken, GermanyDepartment of Biochemistry, University of Cambridge, Cambridge, United KingdomABSTRACT Pseudomonas aeruginosa is an opportunistic human pathogen, particularly noted for causing infections in the lungs of people with cystic fibrosis (CF). Previous studies have shown that the gene expression profile of P. aeruginosa appears to converge toward a common metabolic program as the organism adapts to the CF airway environment. However, we still have only a limited understanding of how these transcriptional changes impact metabolic flux at the systems level. To address this, we analyzed the transcriptome, proteome, and fluxome of P. aeruginosa grown on glycerol or acetate. These carbon sources were chosen because they are the primary breakdown products of an airway surfactant, phosphatidylcholine, which is known to be a major carbon source for P. aeruginosa in CF airways. We show that the fluxes of carbon throughout central metabolism are radically different among carbon sources. For example, the newly recognized “EDEMP cycle” (which incorporates elements of the Entner-Doudoroff [ED] pathway, the Embden-Meyerhof-Parnas [EMP] pathway, and the pentose phosphate [PP] pathway) plays an important role in supplying NADPH during growth on glycerol. In contrast, the EDEMP cycle is attenuated during growth on acetate, and instead, NADPH is primarily supplied by the reaction catalyzed by isocitrate dehydrogenase(s). Perhaps more importantly, our proteomic and transcriptomic analyses revealed a global remodeling of gene expression during growth on the different carbon sources, with unanticipated impacts on aerobic denitrification, electron transport chain architecture, and the redox economy of the cell. Collectively, these data highlight the remarkable metabolic plasticity of P. aeruginosa; that plasticity allows the organism to seamlessly segue between different carbon sources, maximizing the energetic yield from each. IMPORTANCE Pseudomonas aeruginosa is an opportunistic human pathogen that is well known for causing infections in the airways of people with cystic fibrosis. Although it is clear that P. aeruginosa is metabolically well adapted to life in the CF lung, little is currently known about how the organism metabolizes the nutrients available in the airways. In this work, we used a combination of gene expression and isotope tracer (“fluxomic”) analyses to find out exactly where the input carbon goes during growth on two CF-relevant carbon sources, acetate and glycerol (derived from the breakdown of lung surfactant). We found that carbon is routed (“fluxed”) through very different pathways during growth on these substrates and that this is accompanied by an unexpected remodeling of the cell’s electron transfer pathways. Having access to this “blueprint” is important because the metabolism of P. aeruginosa is increasingly being recognized as a target for the development of much-needed antimicrobial agents.https://journals.asm.org/doi/10.1128/mBio.02684-19Pseudomonas aeruginosacarbon metabolismdenitrificationproteomicscarbon fluxacetate metabolism |
| spellingShingle | Stephen K. Dolan Michael Kohlstedt Stephen Trigg Pedro Vallejo Ramirez Clemens F. Kaminski Christoph Wittmann Martin Welch Contextual Flexibility in <named-content content-type="genus-species">Pseudomonas aeruginosa</named-content> Central Carbon Metabolism during Growth in Single Carbon Sources mBio Pseudomonas aeruginosa carbon metabolism denitrification proteomics carbon flux acetate metabolism |
| title | Contextual Flexibility in <named-content content-type="genus-species">Pseudomonas aeruginosa</named-content> Central Carbon Metabolism during Growth in Single Carbon Sources |
| title_full | Contextual Flexibility in <named-content content-type="genus-species">Pseudomonas aeruginosa</named-content> Central Carbon Metabolism during Growth in Single Carbon Sources |
| title_fullStr | Contextual Flexibility in <named-content content-type="genus-species">Pseudomonas aeruginosa</named-content> Central Carbon Metabolism during Growth in Single Carbon Sources |
| title_full_unstemmed | Contextual Flexibility in <named-content content-type="genus-species">Pseudomonas aeruginosa</named-content> Central Carbon Metabolism during Growth in Single Carbon Sources |
| title_short | Contextual Flexibility in <named-content content-type="genus-species">Pseudomonas aeruginosa</named-content> Central Carbon Metabolism during Growth in Single Carbon Sources |
| title_sort | contextual flexibility in named content content type genus species pseudomonas aeruginosa named content central carbon metabolism during growth in single carbon sources |
| topic | Pseudomonas aeruginosa carbon metabolism denitrification proteomics carbon flux acetate metabolism |
| url | https://journals.asm.org/doi/10.1128/mBio.02684-19 |
| work_keys_str_mv | AT stephenkdolan contextualflexibilityinnamedcontentcontenttypegenusspeciespseudomonasaeruginosanamedcontentcentralcarbonmetabolismduringgrowthinsinglecarbonsources AT michaelkohlstedt contextualflexibilityinnamedcontentcontenttypegenusspeciespseudomonasaeruginosanamedcontentcentralcarbonmetabolismduringgrowthinsinglecarbonsources AT stephentrigg contextualflexibilityinnamedcontentcontenttypegenusspeciespseudomonasaeruginosanamedcontentcentralcarbonmetabolismduringgrowthinsinglecarbonsources AT pedrovallejoramirez contextualflexibilityinnamedcontentcontenttypegenusspeciespseudomonasaeruginosanamedcontentcentralcarbonmetabolismduringgrowthinsinglecarbonsources AT clemensfkaminski contextualflexibilityinnamedcontentcontenttypegenusspeciespseudomonasaeruginosanamedcontentcentralcarbonmetabolismduringgrowthinsinglecarbonsources AT christophwittmann contextualflexibilityinnamedcontentcontenttypegenusspeciespseudomonasaeruginosanamedcontentcentralcarbonmetabolismduringgrowthinsinglecarbonsources AT martinwelch contextualflexibilityinnamedcontentcontenttypegenusspeciespseudomonasaeruginosanamedcontentcentralcarbonmetabolismduringgrowthinsinglecarbonsources |