1
|
Brunson DN, Lemos JA. Heme utilization by the enterococci. FEMS MICROBES 2024; 5:xtae019. [PMID: 39070772 PMCID: PMC11282960 DOI: 10.1093/femsmc/xtae019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 06/02/2024] [Accepted: 07/01/2024] [Indexed: 07/30/2024] Open
Abstract
Heme consists of a tetrapyrrole ring ligating an iron ion and has important roles in biological systems. While well-known as the oxygen-binding molecule within hemoglobin of mammals, heme is also cofactor for several enzymes and a major iron source for bacteria within the host. The enterococci are a diverse group of Gram-positive bacteria that exist primarily within the gastrointestinal tract of animals. However, some species within this genus can transform into formidable opportunistic pathogens, largely owing to their extraordinary adaptability to hostile environments. Although enterococci cannot synthesize heme nor depend on heme to grow, several species within the genus encode proteins that utilize heme as a cofactor, which appears to increase their fitness and ability to thrive in challenging environments. This includes more efficient energy generation via aerobic respiration and protection from reactive oxygen species. Here, we review the significance of heme to enterococci, primarily the major human pathogen Enterococcus faecalis, use bioinformatics to assess the prevalence of hemoproteins throughout the genus, and highlight recent studies that underscore the central role of the heme-E. faecalis relationship in host-pathogen dynamics and interspecies bacterial interactions.
Collapse
Affiliation(s)
- Debra N Brunson
- Department of Oral Biology, University of Florida College of Dentistry, 1395 Center Drive, Gainesville, FL 32610, United States
| | - José A Lemos
- Department of Oral Biology, University of Florida College of Dentistry, 1395 Center Drive, Gainesville, FL 32610, United States
| |
Collapse
|
2
|
Smirnova G, Tyulenev A, Sutormina L, Kalashnikova T, Muzyka N, Ushakov V, Samoilova Z, Oktyabrsky O. Regulation of Cysteine Homeostasis and Its Effect on Escherichia coli Sensitivity to Ciprofloxacin in LB Medium. Int J Mol Sci 2024; 25:4424. [PMID: 38674008 PMCID: PMC11050555 DOI: 10.3390/ijms25084424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
Cysteine and its derivatives, including H2S, can influence bacterial virulence and sensitivity to antibiotics. In minimal sulfate media, H2S is generated under stress to prevent excess cysteine and, together with incorporation into glutathione and export into the medium, is a mechanism of cysteine homeostasis. Here, we studied the features of cysteine homeostasis in LB medium, where the main source of sulfur is cystine, whose import can create excess cysteine inside cells. We used mutants in the mechanisms of cysteine homeostasis and a set of microbiological and biochemical methods, including the real-time monitoring of sulfide and oxygen, the determination of cysteine and glutathione (GSH), and the expression of the Fur, OxyR, and SOS regulons genes. During normal growth, the parental strain generated H2S when switching respiration to another substrate. The mutations affected the onset time, the intensity and duration of H2S production, cysteine and glutathione levels, bacterial growth and respiration rates, and the induction of defense systems. Exposure to chloramphenicol and high doses of ciprofloxacin increased cysteine content and GSH synthesis. A high inverse relationship between log CFU/mL and bacterial growth rate before ciprofloxacin addition was revealed. The study points to the important role of maintaining cysteine homeostasis during normal growth and antibiotic exposure in LB medium.
Collapse
Affiliation(s)
- Galina Smirnova
- Institute of Ecology and Genetics of Microorganisms, Perm Federal Research Center, Russian Academy of Sciences, Goleva 13, 614081 Perm, Russia; (A.T.); (L.S.); (T.K.); (N.M.); (V.U.); (Z.S.); (O.O.)
| | | | | | | | | | | | | | | |
Collapse
|
3
|
Caballero Cerbon DA, Gebhard L, Dokuyucu R, Ertl T, Härtl S, Mazhar A, Weuster-Botz D. Challenges and Advances in the Bioproduction of L-Cysteine. Molecules 2024; 29:486. [PMID: 38257399 PMCID: PMC10821248 DOI: 10.3390/molecules29020486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/15/2024] [Accepted: 01/17/2024] [Indexed: 01/24/2024] Open
Abstract
L-cysteine is a proteogenic amino acid with many applications in the pharmaceutical, food, animal feed, and cosmetic industries. Due to safety and environmental issues in extracting L-cysteine from animal hair and feathers, the fermentative production of L-cysteine offers an attractive alternative using renewable feedstocks. Strategies to improve microbial production hosts like Pantoea ananatis, Corynebacterium glutamicum, Pseudomonas sp., and Escherichia coli are summarized. Concerning the metabolic engineering strategies, the overexpression of feedback inhibition-insensitive L-serine O-acetyltransferase and weakening the degradation of L-cysteine through the removal of L-cysteine desulfhydrases are crucial adjustments. The overexpression of L-cysteine exporters is vital to overcome the toxicity caused by intracellular accumulating L-cysteine. In addition, we compiled the process engineering aspects for the bioproduction of L-cysteine. Utilizing the energy-efficient sulfur assimilation pathway via thiosulfate, fermenting cheap carbon sources, designing scalable, fed-batch processes with individual feedings of carbon and sulfur sources, and implementing efficient purification techniques are essential for the fermentative production of L-cysteine on an industrial scale.
Collapse
Affiliation(s)
- Daniel Alejandro Caballero Cerbon
- Chair of Biochemical Engineering, TUM School of Engineering and Design, Technical University of Munich, Boltzmannstraße 15, D-85748 Garching, Germany;
| | - Leon Gebhard
- TUM School of Engineering and Design, Technical University of Munich, Boltzmannstraße 15, D-85748 Garching, Germany
| | - Ruveyda Dokuyucu
- TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Petersgasse 5, D-94315 Straubing, Germany; (R.D.); (T.E.); (S.H.)
| | - Theresa Ertl
- TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Petersgasse 5, D-94315 Straubing, Germany; (R.D.); (T.E.); (S.H.)
| | - Sophia Härtl
- TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Petersgasse 5, D-94315 Straubing, Germany; (R.D.); (T.E.); (S.H.)
| | - Ayesha Mazhar
- TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Petersgasse 5, D-94315 Straubing, Germany; (R.D.); (T.E.); (S.H.)
| | - Dirk Weuster-Botz
- Chair of Biochemical Engineering, TUM School of Engineering and Design, Technical University of Munich, Boltzmannstraße 15, D-85748 Garching, Germany;
| |
Collapse
|
4
|
Abstract
The metabolism of a bacterial cell stretches beyond its boundaries, often connecting with the metabolism of other cells to form extended metabolic networks that stretch across communities, and even the globe. Among the least intuitive metabolic connections are those involving cross-feeding of canonically intracellular metabolites. How and why are these intracellular metabolites externalized? Are bacteria simply leaky? Here I consider what it means for a bacterium to be leaky, and I review mechanisms of metabolite externalization from the context of cross-feeding. Despite common claims, diffusion of most intracellular metabolites across a membrane is unlikely. Instead, passive and active transporters are likely involved, possibly purging excess metabolites as part of homeostasis. Re-acquisition of metabolites by a producer limits the opportunities for cross-feeding. However, a competitive recipient can stimulate metabolite externalization and initiate a positive-feedback loop of reciprocal cross-feeding.
Collapse
Affiliation(s)
- James B McKinlay
- Department of Biology, Indiana University, Bloomington, Indiana, USA;
| |
Collapse
|
5
|
Wu D, Mehdipour AR, Finke F, Goojani HG, Groh RR, Grund TN, Reichhart TMB, Zimmermann R, Welsch S, Bald D, Shepherd M, Hummer G, Safarian S. Dissecting the conformational complexity and mechanism of a bacterial heme transporter. Nat Chem Biol 2023:10.1038/s41589-023-01314-5. [PMID: 37095238 PMCID: PMC10374445 DOI: 10.1038/s41589-023-01314-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 03/14/2023] [Indexed: 04/26/2023]
Abstract
Iron-bound cyclic tetrapyrroles (hemes) are redox-active cofactors in bioenergetic enzymes. However, the mechanisms of heme transport and insertion into respiratory chain complexes remain unclear. Here, we used cellular, biochemical, structural and computational methods to characterize the structure and function of the heterodimeric bacterial ABC transporter CydDC. We provide multi-level evidence that CydDC is a heme transporter required for functional maturation of cytochrome bd, a pharmaceutically relevant drug target. Our systematic single-particle cryogenic-electron microscopy approach combined with atomistic molecular dynamics simulations provides detailed insight into the conformational landscape of CydDC during substrate binding and occlusion. Our simulations reveal that heme binds laterally from the membrane space to the transmembrane region of CydDC, enabled by a highly asymmetrical inward-facing CydDC conformation. During the binding process, heme propionates interact with positively charged residues on the surface and later in the substrate-binding pocket of the transporter, causing the heme orientation to rotate 180°.
Collapse
Affiliation(s)
- Di Wu
- Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt/Main, Germany
| | - Ahmad R Mehdipour
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Frankfurt/Main, Germany
- Center for Molecular Modeling (CMM), Ghent University, Zwijnaarde, Belgium
| | - Franziska Finke
- Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt/Main, Germany
| | - Hojjat G Goojani
- Amsterdam Institute for Life and Environment (A-LIFE), AIMMS, Faculty of Science, Vrije University of Amsterdam, Amsterdam, the Netherlands
| | - Roan R Groh
- Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt/Main, Germany
| | - Tamara N Grund
- Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt/Main, Germany
| | - Thomas M B Reichhart
- Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt/Main, Germany
| | - Rita Zimmermann
- Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt/Main, Germany
| | - Sonja Welsch
- Central Electron Microscopy Facility, Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Dirk Bald
- Amsterdam Institute for Life and Environment (A-LIFE), AIMMS, Faculty of Science, Vrije University of Amsterdam, Amsterdam, the Netherlands
| | - Mark Shepherd
- School of Biosciences, RAPID Group, University of Kent, Canterbury, UK
| | - Gerhard Hummer
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Frankfurt/Main, Germany
- Institute of Biophysics, Goethe University Frankfurt, Frankfurt/Main, Germany
| | - Schara Safarian
- Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Frankfurt/Main, Germany.
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Frankfurt/Main, Germany.
| |
Collapse
|
6
|
Brunson DN, Colomer-Winter C, Lam LN, Lemos JA. Identification of Multiple Iron Uptake Mechanisms in Enterococcus faecalis and Their Relationship to Virulence. Infect Immun 2023; 91:e0049622. [PMID: 36912636 PMCID: PMC10112239 DOI: 10.1128/iai.00496-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 02/17/2023] [Indexed: 03/14/2023] Open
Abstract
Among the unfavorable conditions bacteria encounter within the host is restricted access to essential trace metals such as iron. To overcome iron deficiency, bacteria deploy multiple strategies to scavenge iron from host tissues, with abundant examples of iron acquisition systems being implicated in bacterial pathogenesis. Yet the mechanisms utilized by the major nosocomial pathogen Enterococcus faecalis to maintain intracellular iron balance are poorly understood. In this study, we conducted a systematic investigation to identify and characterize the iron acquisition mechanisms of E. faecalis and to determine their contribution to virulence. Bioinformatic analysis and literature surveys revealed that E. faecalis possesses three conserved iron uptake systems. Through transcriptomics, we discovered two novel ABC-type transporters that mediate iron uptake. While inactivation of a single transporter had minimal impact on the ability of E. faecalis to maintain iron homeostasis, inactivation of all five systems (Δ5Fe strain) disrupted intracellular iron homeostasis and considerably impaired cell growth under iron deficiency. Virulence of the Δ5Fe strain was generally impaired in different animal models but showed niche-specific variations in mouse models, leading us to suspect that heme can serve as an iron source to E. faecalis during mammalian infections. Indeed, heme supplementation restored growth of Δ5Fe under iron depletion and virulence in an invertebrate infection model. This study revealed that the collective contribution of five iron transporters promotes E. faecalis virulence and that the ability to acquire and utilize heme as an iron source is critical to the systemic dissemination of E. faecalis.
Collapse
Affiliation(s)
- Debra N. Brunson
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Cristina Colomer-Winter
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Ling Ning Lam
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - José A. Lemos
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| |
Collapse
|
7
|
Gutensohn M, Schaefer JK, Maas TJ, Skyllberg U, Björn E. Metabolic turnover of cysteine-related thiol compounds at environmentally relevant concentrations by Geobacter sulfurreducens. Front Microbiol 2023; 13:1085214. [PMID: 36713222 PMCID: PMC9874932 DOI: 10.3389/fmicb.2022.1085214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 12/22/2022] [Indexed: 01/12/2023] Open
Abstract
Low-molecular-mass (LMM) thiol compounds are known to be important for many biological processes in various organisms but LMM thiols are understudied in anaerobic bacteria. In this work, we examined the production and turnover of nanomolar concentrations of LMM thiols with a chemical structure related to cysteine by the model iron-reducing bacterium Geobacter sulfurreducens. Our results show that G. sulfurreducens tightly controls the production, excretion and intracellular concentration of thiols depending on cellular growth state and external conditions. The production and cellular export of endogenous cysteine was coupled to the extracellular supply of Fe(II), suggesting that cysteine excretion may play a role in cellular trafficking to iron proteins. Addition of excess exogenous cysteine resulted in a rapid and extensive conversion of cysteine to penicillamine by the cells. Experiments with added isotopically labeled cysteine confirmed that penicillamine was formed by a dimethylation of the C-3 atom of cysteine and not via indirect metabolic responses to cysteine exposure. This is the first report of de novo metabolic synthesis of this compound. Penicillamine formation increased with external exposure to cysteine but the compound did not accumulate intracellularly, which may suggest that it is part of G. sulfurreducens' metabolic strategy to maintain cysteine homeostasis. Our findings highlight and expand on processes mediating homeostasis of cysteine-like LMM thiols in strict anaerobic bacteria. The formation of penicillamine is particularly noteworthy and this compound warrants more attention in microbial metabolism studies.
Collapse
Affiliation(s)
| | - Jeffra K. Schaefer
- Department of Environmental Sciences, Rutgers University, New Brunswick, NJ, United States
| | - Torben J. Maas
- Institute of Inorganic and Analytical Chemistry, University of Münster, Corrensstraße, Münster, Germany
| | - Ulf Skyllberg
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Erik Björn
- Department of Chemistry, Umeå University, Umeå, Sweden,*Correspondence: Erik Björn, ✉
| |
Collapse
|
8
|
Ch'ng JH, Muthu M, Chong KKL, Wong JJ, Tan CAZ, Koh ZJS, Lopez D, Matysik A, Nair ZJ, Barkham T, Wang Y, Kline KA. Heme cross-feeding can augment Staphylococcus aureus and Enterococcus faecalis dual species biofilms. THE ISME JOURNAL 2022; 16:2015-2026. [PMID: 35589966 PMCID: PMC9296619 DOI: 10.1038/s41396-022-01248-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 04/18/2022] [Accepted: 04/29/2022] [Indexed: 12/17/2022]
Abstract
The contribution of biofilms to virulence and as a barrier to treatment is well-established for Staphylococcus aureus and Enterococcus faecalis, both nosocomial pathogens frequently isolated from biofilm-associated infections. Despite frequent co-isolation, their interactions in biofilms have not been well-characterized. We report that in combination, these two species can give rise to augmented biofilms biomass that is dependent on the activation of E. faecalis aerobic respiration. In E. faecalis, respiration requires both exogenous heme to activate the cydAB-encoded heme-dependent cytochrome bd, and the availability of O2. We determined that the ABC transporter encoded by cydDC contributes to heme import. In dual species biofilms, S. aureus provides the heme to activate E. faecalis respiration. S. aureus mutants deficient in heme biosynthesis were unable to augment biofilms whereas heme alone is sufficient to augment E. faecalis mono-species biofilms. Our results demonstrate that S. aureus-derived heme, likely in the form of released hemoproteins, promotes E. faecalis biofilm formation, and that E. faecalis gelatinase activity facilitates heme extraction from hemoproteins. This interspecies interaction and metabolic cross-feeding may explain the frequent co-occurrence of these microbes in biofilm-associated infections.
Collapse
Affiliation(s)
- Jun-Hong Ch'ng
- Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore. .,Department of Surgery Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore. .,Infectious Disease Translational Research Program, National University Health System, Singapore, Singapore. .,Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, Singapore.
| | - Mugil Muthu
- Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore.,Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Kelvin K L Chong
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore.,Nanyang Technological University Institute for Health Technologies, Interdisciplinary Graduate School, Nanyang Technological University, Singapore, Singapore
| | - Jun Jie Wong
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore.,Singapore Centre for Environmental Life Sciences Engineering, Interdisciplinary Graduate Program, Nanyang Technological University, Singapore, Singapore
| | - Casandra A Z Tan
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore.,Singapore Centre for Environmental Life Sciences Engineering, Interdisciplinary Graduate Program, Nanyang Technological University, Singapore, Singapore
| | - Zachary J S Koh
- Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore
| | - Daniel Lopez
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Artur Matysik
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Zeus J Nair
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Timothy Barkham
- Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore.,Department of Laboratory Medicine, Tan Tock Seng Hospital, Singapore, Singapore
| | - Yulan Wang
- Singapore Phenome Center, Lee Kong Chian School of Medicine, Nanyang Technological University, Nanyang, Singapore
| | - Kimberly A Kline
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore. .,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
9
|
Ihara K, Kim S, Ando T, Yoneyama H. Importance of transmembrane helix 4 of l-alanine exporter AlaE in oligomer formation and substrate export activity in Escherichia coli. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35275050 DOI: 10.1099/mic.0.001147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
AlaE is the smallest amino acid exporter identified in Escherichia coli. It exports l-alanine using the proton motive force and plays a pivotal role in maintaining intracellular l-alanine homeostasis by acting as a safety valve. However, our understanding of the molecular mechanisms of substrate export by AlaE is still limited because structural information is lacking. Due to its small size (149 amino acid residues), it has been speculated that AlaE functions by forming an oligomer. In this study, we performed chemical cross-linking and pull-down assays and showed that AlaE indeed generates homo-oligomers as a functional unit. Previous random mutagenesis experiments identified three loss-of-function AlaE point mutations in the predicted transmembrane helix 4 (TM4) region, two of which are present in the GxxxG motif. When alanine-scanning mutagenesis was applied to the TM4 region, the AlaE derivatives that had amino acid substitutions around the GxxxG motif showed low l-alanine export activities, indicating that the GxxxG motif in TM4 plays an important role in substrate export. However, these AlaE variants with low activity could still form oligomers. We therefore concluded that AlaE forms homo-oligomers and that the GxxxG motif in the TM4 region plays an essential role in AlaE activity but is not involved in AlaE oligomer formation.
Collapse
Affiliation(s)
- Kohei Ihara
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi, 980-8572, Japan
| | - Seryoung Kim
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi, 980-8572, Japan
| | - Tasuke Ando
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi, 980-8572, Japan
| | - Hiroshi Yoneyama
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi, 980-8572, Japan
| |
Collapse
|
10
|
Goff JL, Schaefer JK, Yee N. Extracellular sulfite is protective against reactive oxygen species and antibiotic stress in Shewanella oneidensis MR-1. ENVIRONMENTAL MICROBIOLOGY REPORTS 2021; 13:394-400. [PMID: 33870629 DOI: 10.1111/1758-2229.12947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 04/04/2021] [Indexed: 06/12/2023]
Abstract
In this study, we investigated the extracellular reactive sulfur species produced by Shewanella oneidensis MR-1 during growth. The results showed that sulfite is the major extracellular sulfur metabolite released to the growth medium under both aerobic and anaerobic growth conditions. Exogenous sulfite at physiological concentrations protected S. oneidensis MR-1 from hydrogen peroxide toxicity and enhanced tolerance to the beta-lactam antibiotics cefazolin, meropenem, doripenem and ertapenem. These findings suggest that the release of extracellular sulfite is a bacterial defence mechanism that plays a role in the mitigation of environmental stress.
Collapse
Affiliation(s)
- Jennifer L Goff
- Department of Earth and Planetary Sciences, Rutgers University, Piscataway, NJ, USA
| | - Jeffra K Schaefer
- Department of Environmental Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Nathan Yee
- Department of Earth and Planetary Sciences, Rutgers University, Piscataway, NJ, USA
- Department of Environmental Sciences, Rutgers University, New Brunswick, NJ, USA
| |
Collapse
|
11
|
Borisov VB, Siletsky SA, Paiardini A, Hoogewijs D, Forte E, Giuffrè A, Poole RK. Bacterial Oxidases of the Cytochrome bd Family: Redox Enzymes of Unique Structure, Function, and Utility As Drug Targets. Antioxid Redox Signal 2021; 34:1280-1318. [PMID: 32924537 PMCID: PMC8112716 DOI: 10.1089/ars.2020.8039] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 12/23/2022]
Abstract
Significance: Cytochrome bd is a ubiquinol:oxygen oxidoreductase of many prokaryotic respiratory chains with a unique structure and functional characteristics. Its primary role is to couple the reduction of molecular oxygen, even at submicromolar concentrations, to water with the generation of a proton motive force used for adenosine triphosphate production. Cytochrome bd is found in many bacterial pathogens and, surprisingly, in bacteria formally denoted as anaerobes. It endows bacteria with resistance to various stressors and is a potential drug target. Recent Advances: We summarize recent advances in the biochemistry, structure, and physiological functions of cytochrome bd in the light of exciting new three-dimensional structures of the oxidase. The newly discovered roles of cytochrome bd in contributing to bacterial protection against hydrogen peroxide, nitric oxide, peroxynitrite, and hydrogen sulfide are assessed. Critical Issues: Fundamental questions remain regarding the precise delineation of electron flow within this multihaem oxidase and how the extraordinarily high affinity for oxygen is accomplished, while endowing bacteria with resistance to other small ligands. Future Directions: It is clear that cytochrome bd is unique in its ability to confer resistance to toxic small molecules, a property that is significant for understanding the propensity of pathogens to possess this oxidase. Since cytochrome bd is a uniquely bacterial enzyme, future research should focus on harnessing fundamental knowledge of its structure and function to the development of novel and effective antibacterial agents.
Collapse
Affiliation(s)
- Vitaliy B. Borisov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Sergey A. Siletsky
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
| | | | - David Hoogewijs
- Department of Medicine/Physiology, University of Fribourg, Fribourg, Switzerland
| | - Elena Forte
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | | | - Robert K. Poole
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, United Kingdom
| |
Collapse
|
12
|
Ono K, Kitamura Y, Zhang T, Tsutsuki H, Rahman A, Ihara T, Akaike T, Sawa T. Cysteine Hydropersulfide Inactivates β-Lactam Antibiotics with Formation of Ring-Opened Carbothioic S-Acids in Bacteria. ACS Chem Biol 2021; 16:731-739. [PMID: 33781062 DOI: 10.1021/acschembio.1c00027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Hydrogen sulfide (H2S) formed during sulfur metabolism in bacteria has been implicated in the development of intrinsic resistance to antibacterial agents. Despite the conversion of H2S to hydropersulfides greatly enhancing the biochemical properties of H2S such as antioxidant activity, the effects of hydropersulfides on antibiotic resistance have remained unknown. In this work, we investigated the effects of H2S alone or together with cystine to form cysteine hydropersulfide (CysSSH) on the activities of antibacterial agents. By using the disc diffusion test, we found that CysSSH treatment effectively inactivated β-lactams of the penicillin class (penicillin G and ampicillin) and the carbapenem class (meropenem). These β-lactams were resistant to treatment with H2S alone or cystine alone. In contrast, cephalosporin class β-lactams (cefaclor and cefoperazone) and non-β-lactam antibiotics (tetracycline, kanamycin, erythromycin, and ofloxacin) were stable after CysSSH treatment. Chromatographic and mass spectrometric analyses revealed that CysSSH directly reacted with β-lactams to form β-lactam ring-opened carbothioic S-acids (BL-COSH). Furthermore, we demonstrated that certain bacteria (e.g., Escherichia coli and Staphylococcus aureus) efficiently decomposed β-lactam antibiotics to form BL-COSH, which were transported to the extracellular space. These data suggest that CysSSH-mediated β-lactam decomposition may contribute to intrinsic bacterial resistance to β-lactams. BL-COSH may become useful biomarkers for CysSSH-mediated β-lactam resistance and for investigation of potential antibacterial adjuvants that can enhance the antibacterial activity of β-lactams by reducing the hydropersulfides in bacteria.
Collapse
Affiliation(s)
- Katsuhiko Ono
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku Kumamoto 860-8556, Japan
| | - Yusuke Kitamura
- Division of Materials Science and Chemistry, Faculty of Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku Kumamoto 860-8555, Japan
| | - Tianli Zhang
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku Kumamoto 860-8556, Japan
| | - Hiroyasu Tsutsuki
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku Kumamoto 860-8556, Japan
| | - Azizur Rahman
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku Kumamoto 860-8556, Japan
| | - Toshihiro Ihara
- Division of Materials Science and Chemistry, Faculty of Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku Kumamoto 860-8555, Japan
| | - Takaaki Akaike
- Department of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan
| | - Tomohiro Sawa
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku Kumamoto 860-8556, Japan
| |
Collapse
|
13
|
Manceau A, Nagy KL, Glatzel P, Bourdineaud JP. Acute Toxicity of Divalent Mercury to Bacteria Explained by the Formation of Dicysteinate and Tetracysteinate Complexes Bound to Proteins in Escherichia coli and Bacillus subtilis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:3612-3623. [PMID: 33629845 DOI: 10.1021/acs.est.0c05202] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Bacteria are the most abundant organisms on Earth and also the major life form affected by mercury (Hg) poisoning in aquatic and terrestrial food webs. In this study, we applied high energy-resolution X-ray absorption near edge structure (HR-XANES) spectroscopy to bacteria with intracellular concentrations of Hg as low as 0.7 ng/mg (ppm) for identifying the intracellular molecular forms and trafficking pathways of Hg in bacteria at environmentally relevant concentrations. Gram-positive Bacillus subtilis and Gram-negative Escherichia coli were exposed to three Hg species: HgCl2, Hg-dicysteinate (Hg(Cys)2), and Hg-dithioglycolate (Hg(TGA)2). In all cases, Hg was transformed into new two- and four-coordinate cysteinate complexes, interpreted to be bound, respectively, to the consensus metal-binding CXXC motif and zinc finger domains of proteins, with glutathione acting as a transfer ligand. Replacement of zinc cofactors essential to gene regulatory proteins with Hg would inhibit vital functions such as DNA transcription and repair and is suggested to be a main cause of Hg genotoxicity.
Collapse
Affiliation(s)
- Alain Manceau
- Université Grenoble Alpes, CNRS, ISTerre, CS 40700, 38058 Grenoble, France
| | - Kathryn L Nagy
- Department of Earth and Environmental Sciences, University of Illinois at Chicago, MC-186, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Pieter Glatzel
- European Synchrotron Radiation Facility (ESRF), 71 Rue des Martyrs, 38000 Grenoble, France
| | - Jean-Paul Bourdineaud
- Institut Européen de Chimie et Biologie, Université de Bordeaux, CNRS, UMR 5234, 2 rue Escarpit, 33607 Pessac, France
| |
Collapse
|
14
|
Hasenoehrl EJ, Wiggins TJ, Berney M. Bioenergetic Inhibitors: Antibiotic Efficacy and Mechanisms of Action in Mycobacterium tuberculosis. Front Cell Infect Microbiol 2021; 10:611683. [PMID: 33505923 PMCID: PMC7831573 DOI: 10.3389/fcimb.2020.611683] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/23/2020] [Indexed: 11/23/2022] Open
Abstract
Development of novel anti-tuberculosis combination regimens that increase efficacy and reduce treatment timelines will improve patient compliance, limit side-effects, reduce costs, and enhance cure rates. Such advancements would significantly improve the global TB burden and reduce drug resistance acquisition. Bioenergetics has received considerable attention in recent years as a fertile area for anti-tuberculosis drug discovery. Targeting the electron transport chain (ETC) and oxidative phosphorylation machinery promises not only to kill growing cells but also metabolically dormant bacilli that are inherently more drug tolerant. Over the last two decades, a broad array of drugs targeting various ETC components have been developed. Here, we provide a focused review of the current state of art of bioenergetic inhibitors of Mtb with an in-depth analysis of the metabolic and bioenergetic disruptions caused by specific target inhibition as well as their synergistic and antagonistic interactions with other drugs. This foundation is then used to explore the reigning theories on the mechanisms of antibiotic-induced cell death and we discuss how bioenergetic inhibitors in particular fail to be adequately described by these models. These discussions lead us to develop a clear roadmap for new lines of investigation to better understand the mechanisms of action of these drugs with complex mechanisms as well as how to leverage that knowledge for the development of novel, rationally-designed combination therapies to cure TB.
Collapse
Affiliation(s)
- Erik J Hasenoehrl
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Thomas J Wiggins
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Michael Berney
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| |
Collapse
|
15
|
Oz O, Koyuncu I, Gonel A. A Pilot Study for Investigation of Plasma Amino Acid Profile in Neurofibromatosis Type 1 Patients. Comb Chem High Throughput Screen 2020; 25:114-122. [PMID: 33280590 DOI: 10.2174/1386207323666201204143206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 11/01/2020] [Accepted: 11/09/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Neurofibromatosis, also known as Von Recklinghausen disease, is a systemic and progressive genetic disease that primarily affects the skin, eyes, nervous system and bones. The disease can occur in a variety of ways and can vary from individuals. Metabolomic-based research using blood samples has enabled new diagnostic methods to be used in the diagnosis of various diseases, especially cancer. Among metabolites, profiling of plasma free amino acids (PFAA) is a promising approach because PFAAs bind all organ systems and play an important role in metabolism. OBJECTIVE This study aimed to determine the characteristics of PFAA profiles in neurofibromatosis patients and the possibility of using them for early detection and treatment of the disease. METHOD Patients with a diagnosis of Neurofibromatosis Type I confirmed by genetic analysis and healthy individuals of the same age group without any disease were included in the study. We analysed the nineteen plasma free amino acids (phenylalanine, proline, threonine, arginine, asparagine, cystine, valine, glutamate, tyrosine, serine, glutamine, glycine, tryptophane, leucine, lysine, methionine, isoleucine, aspartate and alanine) from neurofibromatosis Type I patients and control group by liquid chromatography tandem mass spectrometry (LC-MS/MS) in Metabolism Laboratory of Harran University Research and Application Hospital. The results of the plasma free amino acid levels were divided into 3 groups as essential, semi-essential and non-essential. The differences of amino acid levels between groups were determined. RESULTS Eight amino acid levels (methionine, arginine, cystine, glutamine, proline, asparagine, serine, aspartate) were significantly altered in patients with neurofibromatosis type 1. In essential amino acids, methionine levels were significantly higher in the patient group than the control group. While the levels of arginine and glutamine in semi-essential amino acids were statistically significantly higher in the patient group, a significant decrease was observed in cystine and proline levels compared to the control group's amino acid levels. In non-essential amino acids group, asparagine, serine and aspartate amino acid levels were significantly higher in the patient group compared to the control group. CONCLUSION The current research predicates that eight amino acids, nsmely methionine, arginine, cystine, glutamine, proline, asparagine, serine, aspartate can be considered to be valuable biomarkers for neurofibromatosis type I. This present study is the first to build models for neurofibromatosis Type I screening using plasma free amino acids and the amino acid profile will guide the predicting of the complications that may occur during the course of the disease.
Collapse
Affiliation(s)
- Ozlem Oz
- Department of Medical Genetics, Harran University. Turkey
| | - Ismail Koyuncu
- Department of Medicinal Biochemistry, Harran University. Turkey
| | - Ataman Gonel
- Department of Medicinal Biochemistry, Harran University. Turkey
| |
Collapse
|
16
|
Jaswal K, Shrivastava M, Roy D, Agrawal S, Chaba R. Metabolism of long-chain fatty acids affects disulfide bond formation in Escherichia coli and activates envelope stress response pathways as a combat strategy. PLoS Genet 2020; 16:e1009081. [PMID: 33079953 PMCID: PMC7598926 DOI: 10.1371/journal.pgen.1009081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 10/30/2020] [Accepted: 08/25/2020] [Indexed: 12/28/2022] Open
Abstract
The envelope of gram-negative bacteria serves as the first line of defense against environmental insults. Therefore, its integrity is continuously monitored and maintained by several envelope stress response (ESR) systems. Due to its oxidizing environment, the envelope represents an important site for disulfide bond formation. In Escherichia coli, the periplasmic oxidoreductase, DsbA introduces disulfide bonds in substrate proteins and transfers electrons to the inner membrane oxidoreductase, DsbB. Under aerobic conditions, the reduced form of DsbB is re-oxidized by ubiquinone, an electron carrier in the electron transport chain (ETC). Given the critical role of ubiquinone in transferring electrons derived from the oxidation of reduced cofactors, we were intrigued whether metabolic conditions that generate a large number of reduced cofactors render ubiquinone unavailable for disulfide bond formation. To test this, here we investigated the influence of metabolism of long-chain fatty acid (LCFA), an energy-rich carbon source, on the redox state of the envelope. We show that LCFA degradation increases electron flow in the ETC. Further, whereas cells metabolizing LCFAs exhibit characteristics of insufficient disulfide bond formation, these hallmarks are averted in cells exogenously provided with ubiquinone. Importantly, the ESR pathways, Cpx and σE, are activated by envelope signals generated during LCFA metabolism. Our results argue that Cpx is the primary ESR that senses and maintains envelope redox homeostasis. Amongst the two ESRs, Cpx is induced to a greater extent by LCFAs and senses redox-dependent signal. Further, ubiquinone accumulation during LCFA metabolism is prevented in cells lacking Cpx response, suggesting that Cpx activation helps maintain redox homeostasis by increasing the oxidizing power for disulfide bond formation. Taken together, our results demonstrate an intricate relationship between cellular metabolism and disulfide bond formation dictated by ETC and ESR, and provide the basis for examining whether similar mechanisms control envelope redox status in other gram-negative bacteria.
Collapse
Affiliation(s)
- Kanchan Jaswal
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
| | - Megha Shrivastava
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
| | - Deeptodeep Roy
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
| | - Shashank Agrawal
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
| | - Rachna Chaba
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
| |
Collapse
|
17
|
CydDC functions as a cytoplasmic cystine reductase to sensitize Escherichia coli to oxidative stress and aminoglycosides. Proc Natl Acad Sci U S A 2020; 117:23565-23570. [PMID: 32900959 DOI: 10.1073/pnas.2007817117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
l-cysteine is the source of all bacterial sulfurous biomolecules. However, the cytoplasmic level of l-cysteine must be tightly regulated due to its propensity to reduce iron and drive damaging Fenton chemistry. It has been proposed that in Escherichia coli the component of cytochrome bd-I terminal oxidase, the CydDC complex, shuttles excessive l-cysteine from the cytoplasm to the periplasm, thereby maintaining redox homeostasis. Here, we provide evidence for an alternative function of CydDC by demonstrating that the cydD phenotype, unlike that of the bona fide l-cysteine exporter eamA, parallels that of the l-cystine importer tcyP. Chromosomal induction of eamA, but not of cydDC, from a strong pLtetO-1 promoter (Ptet) leads to the increased level of extracellular l-cysteine, whereas induction of cydDC or tcyP causes the accumulation of cytoplasmic l-cysteine. Congruently, inactivation of cydD renders cells resistant to hydrogen peroxide and to aminoglycoside antibiotics. In contrast, induction of cydDC sensitizes cells to oxidative stress and aminoglycosides, which can be suppressed by eamA overexpression. Furthermore, inactivation of the ferric uptake regulator (fur) in Ptet-cydDC or Ptet-tcyP cells results in dramatic loss of survival, whereas catalase (katG) overexpression suppresses the hypersensitivity of both strains to H2O2 These results establish CydDC as a reducer of cytoplasmic cystine, as opposed to an l-cysteine exporter, and further elucidate a link between oxidative stress, antibiotic resistance, and sulfur metabolism.
Collapse
|
18
|
Onyeabor M, Martinez R, Kurgan G, Wang X. Engineering transport systems for microbial production. ADVANCES IN APPLIED MICROBIOLOGY 2020; 111:33-87. [PMID: 32446412 DOI: 10.1016/bs.aambs.2020.01.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The rapid development in the field of metabolic engineering has enabled complex modifications of metabolic pathways to generate a diverse product portfolio. Manipulating substrate uptake and product export is an important research area in metabolic engineering. Optimization of transport systems has the potential to enhance microbial production of renewable fuels and chemicals. This chapter comprehensively reviews the transport systems critical for microbial production as well as current genetic engineering strategies to improve transport functions and thus production metrics. In addition, this chapter highlights recent advancements in engineering microbial efflux systems to enhance cellular tolerance to industrially relevant chemical stress. Lastly, future directions to address current technological gaps are discussed.
Collapse
Affiliation(s)
- Moses Onyeabor
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Rodrigo Martinez
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Gavin Kurgan
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Xuan Wang
- School of Life Sciences, Arizona State University, Tempe, AZ, United States.
| |
Collapse
|
19
|
Saini V, Chinta KC, Reddy VP, Glasgow JN, Stein A, Lamprecht DA, Rahman MA, Mackenzie JS, Truebody BE, Adamson JH, Kunota TTR, Bailey SM, Moellering DR, Lancaster JR, Steyn AJC. Hydrogen sulfide stimulates Mycobacterium tuberculosis respiration, growth and pathogenesis. Nat Commun 2020; 11:557. [PMID: 31992699 PMCID: PMC6987094 DOI: 10.1038/s41467-019-14132-y] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 12/13/2019] [Indexed: 01/23/2023] Open
Abstract
Hydrogen sulfide (H2S) is involved in numerous pathophysiological processes and shares overlapping functions with CO and •NO. However, the importance of host-derived H2S in microbial pathogenesis is unknown. Here we show that Mtb-infected mice deficient in the H2S-producing enzyme cystathionine β-synthase (CBS) survive longer with reduced organ burden, and that pharmacological inhibition of CBS reduces Mtb bacillary load in mice. High-resolution respirometry, transcriptomics and mass spectrometry establish that H2S stimulates Mtb respiration and bioenergetics predominantly via cytochrome bd oxidase, and that H2S reverses •NO-mediated inhibition of Mtb respiration. Further, exposure of Mtb to H2S regulates genes involved in sulfur and copper metabolism and the Dos regulon. Our results indicate that Mtb exploits host-derived H2S to promote growth and disease, and suggest that host-directed therapies targeting H2S production may be potentially useful for the management of tuberculosis and other microbial infections. The importance of host-produced hydrogen sulfide (H2S) in microbial pathogenesis is poorly understood. Here, Saini et al. show that H2S alters Mycobacterium tuberculosis (Mtb) central metabolism, stimulates respiration to promote growth and TB disease, and upregulates the Dos regulon.
Collapse
Affiliation(s)
- Vikram Saini
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA.,Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA.,Laboratory of Infection Biology and Translational Research, Department of Biotechnology, All India Institute of Medical Sciences, New Delhi, India
| | - Krishna C Chinta
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Vineel P Reddy
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Joel N Glasgow
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Asaf Stein
- Department of Environment Health Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Dirk A Lamprecht
- Africa Health Research Institute, Durban, South Africa.,Janssen Infectious Diseases and Vaccines, Janssen Pharmaceutica NV, Beerse, Belgium
| | | | | | | | | | | | - Shannon M Bailey
- Department of Environment Health Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Douglas R Moellering
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jack R Lancaster
- Departments of Pharmacology and Chemical Biology, Medicine, and Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Adrie J C Steyn
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA. .,Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA. .,Africa Health Research Institute, Durban, South Africa. .,Center for AIDS Research, University of Alabama at Birmingham, Birmingham, AL, USA.
| |
Collapse
|
20
|
Kishino M, Kondoh M, Hirasawa T. Enhanced L-cysteine production by overexpressing potential L-cysteine exporter genes in an L-cysteine-producing recombinant strain of Corynebacterium glutamicum. Biosci Biotechnol Biochem 2019; 83:2390-2393. [DOI: 10.1080/09168451.2019.1659715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
ABSTRACT
We identified L-cysteine exporter candidates of Corynebacterium glutamicum and investigated the effect of overexpression of the potential L-cysteine exporter genes on L-cysteine production in a recombinant strain of C. glutamicum. Overexpression of NCgl2566 and NCgl0580 resulted in enhanced L-cysteine production in an L-cysteine-producing recombinant strain of C. glutamicum.
Collapse
Affiliation(s)
- Mayumi Kishino
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Mariko Kondoh
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Takashi Hirasawa
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| |
Collapse
|
21
|
Reis AC, Kolvenbach BA, Chami M, Gales L, Egas C, Corvini PFX, Nunes OC. Comparative genomics reveals a novel genetic organization of the sad cluster in the sulfonamide-degrader 'Candidatus Leucobacter sulfamidivorax' strain GP. BMC Genomics 2019; 20:885. [PMID: 31752666 PMCID: PMC6868719 DOI: 10.1186/s12864-019-6206-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 10/21/2019] [Indexed: 02/01/2023] Open
Abstract
Background Microbial communities recurrently establish metabolic associations resulting in increased fitness and ability to perform complex tasks, such as xenobiotic degradation. In a previous study, we have described a sulfonamide-degrading consortium consisting of a novel low-abundant actinobacterium, named strain GP, and Achromobacter denitrificans PR1. However, we found that strain GP was unable to grow independently and could not be further purified. Results Previous studies suggested that strain GP might represent a new putative species within the Leucobacter genus (16S rRNA gene similarity < 97%). In this study, we found that average nucleotide identity (ANI) with other Leucobacter spp. ranged between 76.8 and 82.1%, further corroborating the affiliation of strain GP to a new provisional species. The average amino acid identity (AAI) and percentage of conserved genes (POCP) values were near the lower edge of the genus delimitation thresholds (65 and 55%, respectively). Phylogenetic analysis of core genes between strain GP and Leucobacter spp. corroborated these findings. Comparative genomic analysis indicates that strain GP may have lost genes related to tetrapyrrole biosynthesis and thiol transporters, both crucial for the correct assembly of cytochromes and aerobic growth. However, supplying exogenous heme and catalase was insufficient to abolish the dependent phenotype. The actinobacterium harbors at least two copies of a novel genetic element containing a sulfonamide monooxygenase (sadA) flanked by a single IS1380 family transposase. Additionally, two homologs of sadB (4-aminophenol monooxygenase) were identified in the metagenome-assembled draft genome of strain GP, but these were not located in the vicinity of sadA nor of mobile or integrative elements. Conclusions Comparative genomics of the genus Leucobacter suggested the absence of some genes encoding for important metabolic traits in strain GP. Nevertheless, although media and culture conditions were tailored to supply its potential metabolic needs, these conditions were insufficient to isolate the PR1-dependent actinobacterium further. This study gives important insights regarding strain GP metabolism; however, gene expression and functional studies are necessary to characterize and further isolate strain GP. Based on our data, we propose to classify strain GP in a provisional new species within the genus Leucobacter, ‘Candidatus Leucobacter sulfamidivorax‘.
Collapse
Affiliation(s)
- Ana C Reis
- Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering - LEPABE, Department of Chemical Engineering, University of Porto, Rua Dr. Roberto Frias s/n, 4200-465, Porto, Portugal.,Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Gruendenstrasse 40, 4132, Muttenz, Switzerland
| | - Boris A Kolvenbach
- Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Gruendenstrasse 40, 4132, Muttenz, Switzerland
| | - Mohamed Chami
- BioEM lab, C-Cina, Biozentrum, University of Basel, Mattenstrasse 26, CH-4058, Basel, Switzerland
| | - Luís Gales
- Instituto de Investigação e Inovação em Saúde - i3S, Rua Alfredo Allen 208, 4200-135, Porto, Portugal.,Instituto de Biologia Molecular e Celular - IBMC, Rua Alfredo Allen 208, 4200-135, Porto, Portugal.,Instituto de Ciências Biomédicas Abel Salazar - ICBAS, Rua de Jorge Viterbo Ferreira 228, 4050-313, Porto, Portugal
| | - Conceição Egas
- Next Generation Sequencing Unit, Biocant, BiocantPark, Núcleo 04, Lote 8, 3060-197, Cantanhede, Portugal.,Center for Neuroscience and Cell Biology, University of Coimbra, Faculty of Medicine, Rua Larga, Pólo I, 3004-504, Coimbra, Portugal
| | - Philippe F-X Corvini
- Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Gruendenstrasse 40, 4132, Muttenz, Switzerland
| | - Olga C Nunes
- Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering - LEPABE, Department of Chemical Engineering, University of Porto, Rua Dr. Roberto Frias s/n, 4200-465, Porto, Portugal.
| |
Collapse
|
22
|
Smirnova GV, Tyulenev AV, Bezmaternykh KV, Muzyka NG, Ushakov VY, Oktyabrsky ON. Cysteine homeostasis under inhibition of protein synthesis in Escherichia coli cells. Amino Acids 2019; 51:1577-1592. [PMID: 31617110 DOI: 10.1007/s00726-019-02795-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 10/02/2019] [Indexed: 01/23/2023]
Abstract
Increased intracellular cysteine poses a potential danger to cells due to the high ability of cysteine to reduce free iron and promote the Fenton reaction. Here, we studied ways to maintain cysteine homeostasis in E. coli cells while inhibiting protein synthesis with valine or chloramphenicol. When growing wild-type bacteria on minimal medium with sulfate, an excess of cysteine resulting from the inhibition of protein synthesis is mainly incorporated into glutathione (up to 90%), which, therefore, can be considered as cysteine buffer. The share of hydrogen sulfide, which is the product of cysteine degradation by cysteine synthase B (CysM), does not exceed 1-3%, the rest falls on free cysteine, exported from cells. As a result, intracellular free cysteine is maintained at a low level (about 0.1 mM). The lack of glutathione in the gshA mutant increases H2S production and excretion of cysteine and leads to a threefold increase in the level of intracellular cysteine in response to valine and chloramphenicol. The relA mutants, exposed to valine, produce more H2S, dramatically accelerate the export of glutathione and accumulate more cysteine in the cytoplasm than their parent, which indicates that the regulatory nucleotide (p)ppGpp is involved in maintaining cysteine homeostasis. Disruption of cysteine homeostasis in gshA and relA mutants increases their sensitivity to peroxide stress.
Collapse
Affiliation(s)
- Galina V Smirnova
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, Golev Street 13, 614081, Perm, Russia.
| | - Aleksey V Tyulenev
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, Golev Street 13, 614081, Perm, Russia
| | - Kseniya V Bezmaternykh
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, Golev Street 13, 614081, Perm, Russia
| | - Nadezda G Muzyka
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, Golev Street 13, 614081, Perm, Russia
| | - Vadim Y Ushakov
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, Golev Street 13, 614081, Perm, Russia.,Perm State University, Bukireva Street 15, 614990, Perm, Russia
| | - Oleg N Oktyabrsky
- Institute of Ecology and Genetics of Microorganisms, Russian Academy of Sciences, Golev Street 13, 614081, Perm, Russia.,Perm National Research Polytechnic University, Komsomolsky Pr. 29, 614990, Perm, Russia
| |
Collapse
|
23
|
L-Alanine Exporter, AlaE, of Escherichia coli Functions as a Safety Valve to Enhance Survival under Feast Conditions. Int J Mol Sci 2019; 20:ijms20194942. [PMID: 31591285 PMCID: PMC6801825 DOI: 10.3390/ijms20194942] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 10/03/2019] [Accepted: 10/04/2019] [Indexed: 11/17/2022] Open
Abstract
The intracellular level of amino acids is determined by the balance between their anabolic and catabolic pathways. L-alanine is anabolized by three L-alanine synthesizing enzymes and catabolized by two racemases and D-amino acid dehydrogenase (DadA). In addition, its level is regulated by L-alanine movement across the inner membrane. We identified the novel gene alaE, encoding an L-alanine exporter. To elucidate the physiological function of L-Alanine exporter, AlaE, we determined the susceptibility of alaE-, dadA-, and alaE/dadA-deficient mutants, derived from the wild-type strain MG1655, to L-alanyl-L-alanine (Ala-Ala), which shows toxicity to the L-alanine-nonmetabolizing variant lacking alaE. The dadA-deficient mutant has a similar minimum inhibitory concentration (MIC) (>1.25 mg/mL) to that observed in MG1655. However, alaE- and alaE/dadA-deficient mutants had MICs of 0.04 and 0.0025 mg/mL, respectively. The results suggested that the efficacy of AlaE to relieve stress caused by toxic intracellular accumulation of L-alanine was higher than that of DadA. Consistent with this, the intracellular level of alanine in the alaE-mutant was much higher than that in MG1655 and the dadA-mutant. We, therefore, conclude that AlaE functions as a ‘safety-valve’ to prevent the toxic level accumulation of intracellular L-alanine under a peptide-rich environment, such as within the animal intestine.
Collapse
|
24
|
Anderson MT, Mitchell LA, Sintsova A, Rice KA, Mobley HLT. Sulfur Assimilation Alters Flagellar Function and Modulates the Gene Expression Landscape of Serratia marcescens. mSystems 2019; 4:e00285-19. [PMID: 31387930 PMCID: PMC6687942 DOI: 10.1128/msystems.00285-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 07/24/2019] [Indexed: 11/29/2022] Open
Abstract
Sulfur is an essential nutrient that contributes to cellular redox homeostasis, transcriptional regulation, and translation initiation when incorporated into different biomolecules. Transport and reduction of extracellular sulfate followed by cysteine biosynthesis is a major pathway of bacterial sulfur assimilation. For the opportunistic pathogen Serratia marcescens, function of the cysteine biosynthesis pathway is required for extracellular phospholipase activity and flagellum-mediated surface motility, but little else is known about the influence of sulfur assimilation on the physiology of this organism. In this work, it was determined that an S. marcescens cysteine auxotroph fails to differentiate into hyperflagellated and elongated swarmer cells and that cysteine, but not other organic sulfur molecules, restores swarming motility to these bacteria. The S. marcescens cysteine auxotroph further exhibits reduced transcription of phospholipase, hemolysin, and flagellin genes, each of which is subject to transcriptional control by the flagellar regulatory system. Based on these data and the central role of cysteine in sulfur assimilation, it was reasoned that environmental sulfur availability may contribute to the regulation of these functions in S. marcescens Indeed, bacteria that are starved for sulfate exhibit substantially reduced transcription of the genes for hemolysin, phospholipase, and the FlhD flagellar master regulator. A global transcriptomic analysis further defined a large set of S. marcescens genes that are responsive to extracellular sulfate availability, including genes that encode membrane transport, nutrient utilization, and metabolism functions. Finally, sulfate availability was demonstrated to alter S. marcescens cytolytic activity, suggesting that sulfate assimilation may impact the virulence of this organism.IMPORTANCE Serratia marcescens is a versatile bacterial species that inhabits diverse environmental niches and is capable of pathogenic interactions with host organisms ranging from insects to humans. This report demonstrates for the first time the extensive impacts that environmental sulfate availability and cysteine biosynthesis have on the transcriptome of S. marcescens The finding that greater than 1,000 S. marcescens genes are differentially expressed depending on sulfate availability suggests that sulfur abundance is a crucial factor that controls the physiology of this organism. Furthermore, the high relative expression levels for the putative virulence factors flagella, phospholipase, and hemolysin in the presence of sulfate suggests that a sulfur-rich host environment could contribute to the transcription of these genes during infection.
Collapse
Affiliation(s)
- Mark T Anderson
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Lindsay A Mitchell
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Anna Sintsova
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Katherine A Rice
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Harry L T Mobley
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| |
Collapse
|
25
|
Adediran GA, Liem-Nguyen V, Song Y, Schaefer JK, Skyllberg U, Björn E. Microbial Biosynthesis of Thiol Compounds: Implications for Speciation, Cellular Uptake, and Methylation of Hg(II). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:8187-8196. [PMID: 31257868 DOI: 10.1021/acs.est.9b01502] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Cellular uptake of inorganic divalent mercury (Hg(II)) is a key step in microbial formation of neurotoxic methylmercury (MeHg), but the mechanisms remain largely unidentified. We show that the iron reducing bacterium Geobacter sulfurreducens produces and exports appreciable amounts of low molecular mass thiol (LMM-RSH) compounds reaching concentrations of about 100 nM in the assay medium. These compounds largely control the chemical speciation and bioavailability of Hg(II) by the formation of Hg(LMM-RS)2 complexes (primarily with cysteine) in assays without added thiols. By characterizing these effects, we show that the thermodynamic stability of Hg(II)-complexes is a principal controlling factor for Hg(II) methylation by this bacterium such that less stable complexes with mixed ligation involving LMM-RSH, OH-, and Cl- are methylated at higher rates than the more stable Hg(LMM-RS)2 complexes. The Hg(II) methylation rate across different Hg(LMM-RS)2 compounds is also influenced by the chemical structure of the complexes. In contrast to the current perception of microbial uptake of Hg, our results adhere to generalized theories for metal biouptake based on metal complexation with cell surface ligands and refine the mechanistic understanding of Hg(II) availability for microbial methylation.
Collapse
Affiliation(s)
| | - Van Liem-Nguyen
- Department of Chemistry , Umeå University , SE- 90187 Umeå , Sweden
- School of Science and Technology , Örebro University , SE-70182 Örebro , Sweden
| | - Yu Song
- Department of Forest Ecology and Management , Swedish University of Agricultural Sciences , SE-901 83 Umeå , Sweden
| | - Jeffra K Schaefer
- Department of Environmental Sciences , Rutgers University , 14 College Farm Road , New Brunswick , New Jersey 08901 , United States
| | - Ulf Skyllberg
- Department of Forest Ecology and Management , Swedish University of Agricultural Sciences , SE-901 83 Umeå , Sweden
| | - Erik Björn
- Department of Chemistry , Umeå University , SE- 90187 Umeå , Sweden
| |
Collapse
|
26
|
Poole RK, Cozens AG, Shepherd M. The CydDC family of transporters. Res Microbiol 2019; 170:407-416. [PMID: 31279084 DOI: 10.1016/j.resmic.2019.06.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 06/12/2019] [Accepted: 06/25/2019] [Indexed: 12/23/2022]
Abstract
The CydDC family of ABC transporters export the low molecular weight thiols glutathione and cysteine to the periplasm of a variety of bacterial species. The CydDC complex has previously been shown to be important for disulfide folding, motility, respiration, and tolerance to nitric oxide and antibiotics. In addition, CydDC is thus far unique amongst ABC transporters in that it binds a haem cofactor that appears to modulate ATPase activity. CydDC has a diverse impact upon bacterial metabolism, growth, and virulence, and is of interest to those working on membrane transport mechanisms, redox biology, aerobic respiration, and stress sensing/tolerance during infection.
Collapse
Affiliation(s)
- Robert K Poole
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, United Kingdom
| | - Adam G Cozens
- School of Biosciences, University of Kent, Canterbury, United Kingdom
| | - Mark Shepherd
- School of Biosciences, University of Kent, Canterbury, United Kingdom.
| |
Collapse
|
27
|
Wendisch VF. Metabolic engineering advances and prospects for amino acid production. Metab Eng 2019; 58:17-34. [PMID: 30940506 DOI: 10.1016/j.ymben.2019.03.008] [Citation(s) in RCA: 142] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 03/26/2019] [Accepted: 03/26/2019] [Indexed: 11/18/2022]
Abstract
Amino acid fermentation is one of the major pillars of industrial biotechnology. The multi-billion USD amino acid market is rising steadily and is diversifying. Metabolic engineering is no longer focused solely on strain development for the bulk amino acids L-glutamate and L-lysine that are produced at the million-ton scale, but targets specialty amino acids. These demands are met by the development and application of new metabolic engineering tools including CRISPR and biosensor technologies as well as production processes by enabling a flexible feedstock concept, co-production and co-cultivation schemes. Metabolic engineering advances are exemplified for specialty proteinogenic amino acids, cyclic amino acids, omega-amino acids, and amino acids functionalized by hydroxylation, halogenation and N-methylation.
Collapse
Affiliation(s)
- Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology and Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany.
| |
Collapse
|
28
|
H 2S, a Bacterial Defense Mechanism against the Host Immune Response. Infect Immun 2018; 87:IAI.00272-18. [PMID: 30323021 DOI: 10.1128/iai.00272-18] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 10/04/2018] [Indexed: 12/21/2022] Open
Abstract
The biological mediator hydrogen sulfide (H2S) is produced by bacteria and has been shown to be cytoprotective against oxidative stress and to increase the sensitivity of various bacteria to a range of antibiotic drugs. Here we evaluated whether bacterial H2S provides resistance against the immune response, using two bacterial species that are common sources of nosocomial infections, Escherichia coli and Staphylococcus aureus Elevations in H2S levels increased the resistance of both species to immune-mediated killing. Clearances of infections with wild-type and genetically H2S-deficient E. coli and S. aureus were compared in vitro and in mouse models of abdominal sepsis and burn wound infection. Also, inhibitors of H2S-producing enzymes were used to assess bacterial killing by leukocytes. We found that inhibition of bacterial H2S production can increase the susceptibility of both bacterial species to rapid killing by immune cells and can improve bacterial clearance after severe burn, an injury that increases susceptibility to opportunistic infections. These findings support the role of H2S as a bacterial defense mechanism against the host response and implicate bacterial H2S inhibition as a potential therapeutic intervention in the prevention or treatment of infections.
Collapse
|
29
|
Sun W, Liu C, Zhang F, Zhao M, Li Z. Comparative Genomics Provides Insights Into the Marine Adaptation in Sponge-Derived Kocuriaflava S43. Front Microbiol 2018; 9:1257. [PMID: 29937765 PMCID: PMC6002675 DOI: 10.3389/fmicb.2018.01257] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Accepted: 05/24/2018] [Indexed: 11/13/2022] Open
Abstract
Sponge-derived actinomycetes represent a significant component of marine actinomycetes. Members of the genus Kocuria are distributed in various habitats such as soil, rhizosphere, clinical specimens, marine sediments, and sponges, however, to date, little is known about the mechanism of their environmental adaptation. Kocuria flava S43 was isolated from a coastal sponge. Phylogenetic analysis revealed that it was closely related to the terrestrial airborne K. flava HO-9041. In this study, to gain insights into the marine adaptation in K. flava S43 we sequenced the draft genome for K. flava S43 by third generation sequencing (TGS) and compared it with those of K. flava HO-9041 and some other Kocuria relatives. Comparative genomics and phylogenetic analyses revealed that K. flava S43 might adapt to the marine environment mainly by increasing the number of the genes linked to potassium homeostasis, resistance to heavy metals and phosphate metabolism, and acquiring the genes associated with electron transport and the genes encoding ATP-binding cassette (ABC) transporter, aquaporin, and thiol/disulfide interchange protein. Notably, gene acquisition was probably a primary mechanism of environmental adaptation in K. flava S43. Furthermore, this study also indicated that the Kocuria isolates from various marine and hyperosmotic environments possessed common genetic basis for environmental adaptation.
Collapse
Affiliation(s)
- Wei Sun
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Changrong Liu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Fengli Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Mingzhu Zhao
- Instrumental Analysis Center, Shanghai Jiao Tong University, Shanghai, China
| | - Zhiyong Li
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
30
|
Complete genome sequence of " Thiodictyon syntrophicum" sp. nov. strain Cad16 T, a photolithoautotrophic purple sulfur bacterium isolated from the alpine meromictic Lake Cadagno. Stand Genomic Sci 2018; 13:14. [PMID: 29774086 PMCID: PMC5944118 DOI: 10.1186/s40793-018-0317-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 04/24/2018] [Indexed: 11/16/2022] Open
Abstract
“Thiodictyon syntrophicum” sp. nov. strain Cad16T is a photoautotrophic purple sulfur bacterium belonging to the family of Chromatiaceae in the class of Gammaproteobacteria. The type strain Cad16T was isolated from the chemocline of the alpine meromictic Lake Cadagno in Switzerland. Strain Cad16T represents a key species within this sulfur-driven bacterial ecosystem with respect to carbon fixation. The 7.74-Mbp genome of strain Cad16T has been sequenced and annotated. It encodes 6237 predicted protein sequences and 59 RNA sequences. Phylogenetic comparison based on 16S rRNA revealed that Thiodictyon elegans strain DSM 232T the most closely related species. Genes involved in sulfur oxidation, central carbon metabolism and transmembrane transport were found. Noteworthy, clusters of genes encoding the photosynthetic machinery and pigment biosynthesis are found on the 0.48 Mb plasmid pTs485. We provide a detailed insight into the Cad16T genome and analyze it in the context of the microbial ecosystem of Lake Cadagno.
Collapse
|
31
|
Gu H, Yang Y, Wang M, Chen S, Wang H, Li S, Ma Y, Wang J. Novel Cysteine Desulfidase CdsB Involved in Releasing Cysteine Repression of Toxin Synthesis in Clostridium difficile. Front Cell Infect Microbiol 2018; 7:531. [PMID: 29376034 PMCID: PMC5767170 DOI: 10.3389/fcimb.2017.00531] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 12/18/2017] [Indexed: 01/05/2023] Open
Abstract
Clostridium difficile, a major cause of nosocomial diarrhea and pseudomembranous colitis, still poses serious health-care challenges. The expression of its two main virulence factors, TcdA and TcdB, is reportedly repressed by cysteine, but molecular mechanism remains unclear. The cysteine desulfidase CdsB affects the virulence and infection progresses of some bacteria. The C. difficile strain 630 genome encodes a homolog of CdsB, and in the present study, we analyzed its role in C. difficile 630Δerm by constructing an isogenic ClosTron-based cdsB mutant. When C. difficile was cultured in TY broth supplemented with cysteine, the cdsB gene was rapidly induced during the exponential growth phase. The inactivation of cdsB not only affected the resistance of C. difficile to cysteine, but also altered the expression levels of intracellular cysteine-degrading enzymes and the production of hydrogen sulfide. This suggests that C. difficile CdsB is a major inducible cysteine-degrading enzyme. The inactivation of the cdsB gene in C. difficile also removed the cysteine-dependent repression of toxin production, but failed to remove the Na2S-dependent repression, which supports that the cysteine-dependent repression of toxin production is probably attributable to the accumulation of cysteine by-products. We also mapped a δ54 (SigL)-dependent promoter upstream from the cdsB gene, and cdsB expression was not induced in response to cysteine in the cdsR::ermB or sigL::ermB strain. Using a reporter gene fusion analysis, we identified the necessary promoter sequence for cysteine-dependent cdsB expression. Taken together, these results indicate that CdsB is a key inducible cysteine desulfidase in C. difficile which is regulated by δ54 and CdsR in response to cysteine and that cysteine-dependent regulation of toxin production is closely associated with cysteine degradation.
Collapse
Affiliation(s)
- Huawei Gu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Yingyin Yang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Meng Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Shuyi Chen
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Haiying Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Shan Li
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Yi Ma
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Jufang Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| |
Collapse
|
32
|
Delaunay-Moisan A, Ponsero A, Toledano MB. Reexamining the Function of Glutathione in Oxidative Protein Folding and Secretion. Antioxid Redox Signal 2017; 27:1178-1199. [PMID: 28791880 DOI: 10.1089/ars.2017.7148] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
SIGNIFICANCE Disturbance of glutathione (GSH) metabolism is a hallmark of numerous diseases, yet GSH functions are poorly understood. One key to this question is to consider its functional compartmentation. GSH is present in the endoplasmic reticulum (ER), where it competes with substrates for oxidation by the oxidative folding machinery, composed in eukaryotes of the thiol oxidase Ero1 and proteins from the disulfide isomerase family (protein disulfide isomerase). Yet, whether GSH is required for proper ER oxidative protein folding is a highly debated question. Recent Advances: Oxidative protein folding has been thoroughly dissected over the past decades, and its actors and their mode of action elucidated. Genetically encoded GSH probes have recently provided an access to subcellular redox metabolism, including the ER. CRITICAL ISSUES Of the few often-contradictory models of the role of GSH in the ER, the most popular suggest it serves as reducing power. Yet, as a reductant, GSH also activates Ero1, which questions how GSH can nevertheless support protein reduction. Hence, whether GSH operates in the ER as a reductant, an oxidant, or just as a "blank" compound mirroring ER/periplasm redox activity is a highly debated question, which is further stimulated by the puzzling occurrence of GSH in the Escherichia coli periplasmic "secretory" compartment, aside from the Dsb thiol-reducing and oxidase pathways. FUTURE DIRECTIONS Addressing the mechanisms controlling GSH traffic in and out of the ER/periplasm and its recycling will help address GSH function in secretion. In addition, as thioredoxin reductase was recently implicated in ER oxidative protein folding, the relative contribution of each of these two reducing pathways should now be addressed. Antioxid. Redox Signal. 27, 1178-1199.
Collapse
Affiliation(s)
- Agnès Delaunay-Moisan
- Institute for Integrative Biology of the Cell (I2BC), LSOC, SBIGEM, CEA, CNRS, Université Paris-Sud , Université Paris-Saclay, Gif-sur-Yvette, France
| | - Alise Ponsero
- Institute for Integrative Biology of the Cell (I2BC), LSOC, SBIGEM, CEA, CNRS, Université Paris-Sud , Université Paris-Saclay, Gif-sur-Yvette, France
| | - Michel B Toledano
- Institute for Integrative Biology of the Cell (I2BC), LSOC, SBIGEM, CEA, CNRS, Université Paris-Sud , Université Paris-Saclay, Gif-sur-Yvette, France
| |
Collapse
|
33
|
Nagy YI, Hussein MMM, Ragab YM, Attia AS. Isogenic mutations in the Moraxella catarrhalis CydDC system display pleiotropic phenotypes and reveal the role of a palindrome sequence in its transcriptional regulation. Microbiol Res 2017. [PMID: 28647125 DOI: 10.1016/j.micres.2017.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Moraxella catarrhalis is becoming an important human respiratory tract pathogen affecting significant proportions from the population. However, still little is known about its physiology and molecular regulation. To this end, the CydDC, which is a heterodimeric ATP binding cassette transporter that has been shown to contribute to the maintenance of the redox homeostasis across the periplasm in other Gram-negative bacteria, is studied here. Amino acids multiple sequence alignments indicated that M. catarrhalis CydC is different from the CydC proteins of the bacterial species in which this system has been previously studied. These findings prompted further interest in studying this system in M. catarrhalis. Isogenic mutant in the CydDC system showed suppression in growth rate, hypersensitivity to oxidative and reductive stress and increased accumulation of intracellular cysteine levels. In addition, the growth of cydC- mutant exhibited hypersensitivity to exogenous cysteine; however, it did not display a significant difference from its wild-type counterpart in the murine pulmonary clearance model. Moreover, a palindrome was detected 94bp upstream of the cydD ORF suggesting it might act as a potential regulatory element. Real-time reverse transcription-PCR analysis showed that deletion/change in the palindrome resulted into alterations in the transcription levels of cydC. A better understanding of such system and its regulation helps in developing better ways to combat M. catarrhalis infections.
Collapse
Affiliation(s)
- Yosra I Nagy
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt
| | - Manal M M Hussein
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt
| | - Yasser M Ragab
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt
| | - Ahmed S Attia
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt.
| |
Collapse
|
34
|
Ihara K, Sato K, Hori H, Makino Y, Shigenobu S, Ando T, Isogai E, Yoneyama H. Expression of the alaE gene is positively regulated by the global regulator Lrp in response to intracellular accumulation of l-alanine in Escherichia coli. J Biosci Bioeng 2017; 123:444-450. [PMID: 28057466 DOI: 10.1016/j.jbiosc.2016.11.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 11/10/2016] [Accepted: 11/29/2016] [Indexed: 10/20/2022]
Abstract
The alaE gene in Escherichia coli encodes an l-alanine exporter that catalyzes the active export of l-alanine using proton electrochemical potential. In our previous study, alaE expression was shown to increase in the presence of l-alanyl-l-alanine (Ala-Ala). In this study, the global regulator leucine-responsive regulatory protein (Lrp) was identified as an activator of the alaE gene. A promoter less β-galactosidase gene was fused to an alaE upstream region (240 nucleotides). Cells that were lacZ-deficient and harbored this reporter plasmid showed significant induction of β-galactosidase activity (approximately 17-fold) in the presence of 6 mM l-alanine, l-leucine, and Ala-Ala. However, a reporter plasmid possessing a smaller alaE upstream region (180 nucleotides) yielded transformants with strikingly low enzyme activity under the same conditions. In contrast, lrp-deficient cells showed almost no β-galactosidase induction, indicating that Lrp positively regulates alaE expression. We next performed an electrophoretic mobility shift assay (EMSA) and a DNase I footprinting assay using purified hexahistidine-tagged Lrp (Lrp-His). Consequently, we found that Lrp-His binds to the alaE upstream region spanning nucleotide -161 to -83 with a physiologically relevant affinity (apparent KD, 288.7 ± 83.8 nM). Furthermore, the binding affinity of Lrp-His toward its cis-element was increased by l-alanine and l-leucine, but not by Ala-Ala and d-alanine. Based on these results, we concluded that the gene expression of the alaE is regulated by Lrp in response to intracellular levels of l-alanine, which eventually leads to intracellular homeostasis of l-alanine concentrations.
Collapse
Affiliation(s)
- Kohei Ihara
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Kazuki Sato
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Hatsuhiro Hori
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Yumiko Makino
- NIBB Core Research Facilities, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Aichi, Japan
| | - Shuji Shigenobu
- NIBB Core Research Facilities, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki 444-8585, Aichi, Japan
| | - Tasuke Ando
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Emiko Isogai
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Hiroshi Yoneyama
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan.
| |
Collapse
|
35
|
Stacy A, Abraham N, Jorth P, Whiteley M. Microbial Community Composition Impacts Pathogen Iron Availability during Polymicrobial Infection. PLoS Pathog 2016; 12:e1006084. [PMID: 27973608 PMCID: PMC5156373 DOI: 10.1371/journal.ppat.1006084] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 11/21/2016] [Indexed: 01/07/2023] Open
Abstract
Iron is an essential nutrient for bacterial pathogenesis, but in the host, iron is tightly sequestered, limiting its availability for bacterial growth. Although this is an important arm of host immunity, most studies examine how bacteria respond to iron restriction in laboratory rather than host settings, where the microbiome can potentially alter pathogen strategies for acquiring iron. One of the most important transcriptional regulators controlling bacterial iron homeostasis is Fur. Here we used a combination of RNA-seq and chromatin immunoprecipitation (ChIP)-seq to characterize the iron-restricted and Fur regulons of the biofilm-forming opportunistic pathogen Aggregatibacter actinomycetemcomitans. We discovered that iron restriction and Fur regulate 4% and 3.5% of the genome, respectively. While most genes in these regulons were related to iron uptake and metabolism, we found that Fur also directly regulates the biofilm-dispersing enzyme Dispersin B, allowing A. actinomycetemcomitans to escape from iron-scarce environments. We then leveraged these datasets to assess the availability of iron to A. actinomycetemcomitans in its primary infection sites, abscesses and the oral cavity. We found that A. actinomycetemcomitans is not restricted for iron in a murine abscess mono-infection, but becomes restricted for iron upon co-infection with the oral commensal Streptococcus gordonii. Furthermore, in the transition from health to disease in human gum infection, A. actinomycetemcomitans also becomes restricted for iron. These results suggest that host iron availability is heterogeneous and dependent on the infecting bacterial community. One of the most well-studied phenomena in microbiology is nutritional immunity, or how the host withholds nutrients such as iron to combat infection. As part of this, researchers have characterized how many pathogens respond to iron restriction. However, these studies are often conducted in laboratory media rather than the host. As a result, they overlook how the host environment, such as its microbiome, might alter pathogen behavior regarding iron during infection. To address this gap, we used an opportunistic pathogen that causes abscess and oral cavity infections. We defined how it responds to iron restriction in vitro and then used this data to assess its iron status in vivo. Our results show that in mono-culture abscesses the pathogen is not starved for iron but in co-culture abscesses and multispecies gum disease it is starved for iron. Therefore, host environments are not uniformly restricted for iron, and the microbiome can modulate iron availability to pathogens.
Collapse
Affiliation(s)
- Apollo Stacy
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, John Ring LaMontagne Center for Infectious Disease, The University of Texas at Austin, Austin, TX United States of America
| | - Nader Abraham
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, John Ring LaMontagne Center for Infectious Disease, The University of Texas at Austin, Austin, TX United States of America
| | - Peter Jorth
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, John Ring LaMontagne Center for Infectious Disease, The University of Texas at Austin, Austin, TX United States of America
| | - Marvin Whiteley
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, John Ring LaMontagne Center for Infectious Disease, The University of Texas at Austin, Austin, TX United States of America
- * E-mail:
| |
Collapse
|
36
|
The CydDC ABC transporter of Escherichia coli: new roles for a reductant efflux pump. Biochem Soc Trans 2016; 43:908-12. [PMID: 26517902 DOI: 10.1042/bst20150098] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The CydDC complex of Escherichia coli is a heterodimeric ATP-binding cassette (ABC) transporter that exports cysteine and glutathione to the periplasm. These reductants are thought to modulate periplasmic redox poise, impacting upon the disulfide folding of periplasmic and secreted proteins involved in bacterial virulence. Diminished CydDC activity abolishes the assembly of functional bd-type respiratory oxidases and perturbs haem ligation during the assembly of c-type cytochromes. The focus herein is upon a newly-discovered interaction of the CydDC complex with a haem cofactor; haem has recently been shown to modulate CydDC activity and structural modelling reveals a potential haem-binding site on the periplasmic surface of the complex. These findings have important implications for future investigations into the potential roles for the CydDC-bound haem in redox sensing and tolerance to nitric oxide (NO).
Collapse
|
37
|
Bacterial Cysteine-Inducible Cysteine Resistance Systems. J Bacteriol 2016; 198:1384-92. [PMID: 26883827 DOI: 10.1128/jb.01039-15] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Accepted: 02/12/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Cysteine donates sulfur to macromolecules and occurs naturally in many proteins. Because low concentrations of cysteine are cytotoxic, its intracellular concentration is stringently controlled. In bacteria, cysteine biosynthesis is regulated by feedback inhibition of the activities of serine acetyltransferase (SAT) and 3-phosphoglycerate dehydrogenase (3-PGDH) and is also regulated at the transcriptional level by inducing the cysteine regulon using the master regulator CysB. Here, we describe two novel cysteine-inducible systems that regulate the cysteine resistance of Pantoea ananatis, a member of the family Enterobacteriaceae that shows great potential for producing substances useful for biotechnological, medical, and industrial purposes. One locus, designated ccdA(formerly PAJ_0331), encodes a novel cysteine-inducible cysteine desulfhydrase (CD) that degrades cysteine, and its expression is controlled by the transcriptional regulator encoded byccdR(formerly PAJ_0332 orybaO), located just upstream of ccdA The other locus, designated cefA (formerly PAJ_3026), encodes a novel cysteine-inducible cysteine efflux pump that is controlled by the transcriptional regulator cefR(formerly PAJ_3027), located just upstream of cefA To our knowledge, this is the first example where the expression of CD and an efflux pump is regulated in response to cysteine and is directly involved in imparting resistance to excess levels of cysteine. We propose that ccdA and cefA function as safety valves that maintain homeostasis when the intra- or extracellular cysteine concentration fluctuates. Our findings contribute important insights into optimizing the production of cysteine and related biomaterials by P. ananatis IMPORTANCE Because of its toxicity, the bacterial intracellular cysteine level is stringently regulated at biosynthesis. This work describes the identification and characterization of two novel cysteine-inducible systems that regulate, through degradation and efflux, the cysteine resistance of Pantoea ananatis, a member of the family Enterobacteriaceae that shows great potential for producing substances useful for industrial purposes. We propose that this novel mechanism for sensing and regulating cysteine levels is a safety valve enabling adaptation to sudden changes in intra- or extracellular cysteine levels in bacteria. Our findings provide important insights into optimizing the production of cysteine and related biomaterials by P. ananatis and also a deep understanding of sulfur/cysteine metabolism and regulation in this plant pathogen and related bacteria.
Collapse
|
38
|
Truong QL, Cho Y, Park S, Park BK, Hahn TW. Brucella abortus mutants lacking ATP-binding cassette transporter proteins are highly attenuated in virulence and confer protective immunity against virulent B. abortus challenge in BALB/c mice. Microb Pathog 2016; 95:175-185. [PMID: 27057678 DOI: 10.1016/j.micpath.2016.04.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 10/23/2015] [Accepted: 04/01/2016] [Indexed: 11/30/2022]
Abstract
Brucella abortus RB51 is an attenuated vaccine strain that has been most frequently used for bovine brucellosis. Although it is known to provide good protection in cattle, it still has some drawbacks including resistance to rifampicin, residual virulence and pathogenicity in humans. Thus, there has been a continuous interest on new safe and effective bovine vaccine candidates. In the present study, we have constructed unmarked mutants by deleting singly cydD and cydC genes, which encode ATP-binding cassette transporter proteins, from the chromosome of the virulent Brucella abortus isolate from Korean cow (referred to as IVK15). Both IVK15ΔcydD and ΔcydC mutants showed increased sensitivity to metal ions, hydrogen peroxide and acidic pH, which are mimic to intracellular environment during host infection. Additionally, the mutants exhibited a significant growth defect in RAW264.7 cells and greatly attenuated in mice. Vaccination of mice with either IVK15ΔcydC or IVK15ΔcydD mutant could elicit an anti-Brucella specific immunoglobulin G (IgG) and IgG subclass responses as well as enhance the secretion of interferon-gamma, and provided better protection against challenge with B. abortus strain 2308 than with the commercial B. abortus strain RB51 vaccine. Collectively, these results suggest that both IVK15ΔcydC and IVK15ΔcydD mutants could be an attenuated vaccine candidate against B. abortus.
Collapse
Affiliation(s)
- Quang Lam Truong
- College of Veterinary Medicine, Kangwon National University, Chuncheon 200-701, Gangwon-do, South Korea
| | - Youngjae Cho
- College of Veterinary Medicine, Kangwon National University, Chuncheon 200-701, Gangwon-do, South Korea
| | - Soyeon Park
- College of Veterinary Medicine, Kangwon National University, Chuncheon 200-701, Gangwon-do, South Korea
| | - Bo-Kyoung Park
- College of Veterinary Medicine, Kangwon National University, Chuncheon 200-701, Gangwon-do, South Korea
| | - Tae-Wook Hahn
- College of Veterinary Medicine, Kangwon National University, Chuncheon 200-701, Gangwon-do, South Korea.
| |
Collapse
|
39
|
Holyoake LV, Hunt S, Sanguinetti G, Cook GM, Howard MJ, Rowe ML, Poole RK, Shepherd M. CydDC-mediated reductant export in Escherichia coli controls the transcriptional wiring of energy metabolism and combats nitrosative stress. Biochem J 2016; 473:693-701. [PMID: 26699904 PMCID: PMC4785604 DOI: 10.1042/bj20150536] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 12/18/2015] [Accepted: 12/21/2015] [Indexed: 01/04/2023]
Abstract
The glutathione/cysteine exporter CydDC maintains redox balance in Escherichia coli. A cydD mutant strain was used to probe the influence of CydDC upon reduced thiol export, gene expression, metabolic perturbations, intracellular pH homoeostasis and tolerance to nitric oxide (NO). Loss of CydDC was found to decrease extracytoplasmic thiol levels, whereas overexpression diminished the cytoplasmic thiol content. Transcriptomic analysis revealed a dramatic up-regulation of protein chaperones, protein degradation (via phenylpropionate/phenylacetate catabolism), β-oxidation of fatty acids and genes involved in nitrate/nitrite reduction. (1)H NMR metabolomics revealed elevated methionine and betaine and diminished acetate and NAD(+) in cydD cells, which was consistent with the transcriptomics-based metabolic model. The growth rate and ΔpH, however, were unaffected, although the cydD strain did exhibit sensitivity to the NO-releasing compound NOC-12. These observations are consistent with the hypothesis that the loss of CydDC-mediated reductant export promotes protein misfolding, adaptations to energy metabolism and sensitivity to NO. The addition of both glutathione and cysteine to the medium was found to complement the loss of bd-type cytochrome synthesis in a cydD strain (a key component of the pleiotropic cydDC phenotype), providing the first direct evidence that CydDC substrates are able to restore the correct assembly of this respiratory oxidase. These data provide an insight into the metabolic flexibility of E. coli, highlight the importance of bacterial redox homoeostasis during nitrosative stress, and report for the first time the ability of periplasmic low molecular weight thiols to restore haem incorporation into a cytochrome complex.
Collapse
Affiliation(s)
| | - Stuart Hunt
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, U.K
| | - Guido Sanguinetti
- School of Informatics, The University of Edinburgh, Informatics Forum, 10 Crichton Street, Edinburgh EH8 9AB, U.K
| | - Gregory M Cook
- Department of Microbiology and Immunology, University of Otago, P.O. Box 56, 720 Cumberland Street, Dunedin 9054, New Zealand
| | - Mark J Howard
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, U.K
| | - Michelle L Rowe
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, U.K
| | - Robert K Poole
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, U.K
| | - Mark Shepherd
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, U.K.
| |
Collapse
|
40
|
Toyoda K, Inui M. The extracytoplasmic function σ factor σ(C) regulates expression of a branched quinol oxidation pathway in Corynebacterium glutamicum. Mol Microbiol 2016; 100:486-509. [PMID: 26789738 DOI: 10.1111/mmi.13330] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2016] [Indexed: 11/30/2022]
Abstract
Bacteria modify their expression of different terminal oxidases in response to oxygen availability. Corynebacterium glutamicum, a facultative anaerobic bacterium of the phylum Actinobacteria, possesses aa3 -type cytochrome c oxidase and cytochrome bd-type quinol oxidase, the latter of which is induced by oxygen limitation. We report that an extracytoplasmic function σ factor, σ(C) , is responsible for the regulation of this process. Chromatin immunoprecipitation with microarray analysis detected eight σ(C) -binding regions in the genome, facilitating the identification of a consensus promoter sequence for σ(C) recognition. The promoter sequences were found upstream of genes for cytochrome bd, heme a synthesis enzymes and uncharacterized membrane proteins, all of which were upregulated by sigC overexpression. However, one consensus promoter sequence found on the antisense strand upstream of an operon encoding the cytochrome bc1 complex conferred a σ(C) -dependent negative effect on expression of the operon. The σ(C) regulon was induced by cytochrome aa3 deficiency without modifying sigC expression, but not by bc1 complex deficiency. These findings suggest that σ(C) is activated in response to impaired electron transfer via cytochrome aa3 and not directly to a shift in oxygen levels. Our results reveal a new paradigm for transcriptional regulation of the aerobic respiratory system in bacteria.
Collapse
Affiliation(s)
- Koichi Toyoda
- Research institute of Innovative Technology for the Earth (RITE), 9-2 Kizugawadai, Kizugawa, Kyoto, 619-0292, Japan
| | - Masayuki Inui
- Research institute of Innovative Technology for the Earth (RITE), 9-2 Kizugawadai, Kizugawa, Kyoto, 619-0292, Japan.,Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma, Nara, 630-0101, Japan
| |
Collapse
|
41
|
l-Cysteine Metabolism and Fermentation in Microorganisms. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 159:129-151. [DOI: 10.1007/10_2016_29] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
42
|
Exporters for Production of Amino Acids and Other Small Molecules. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 159:199-225. [PMID: 27832297 DOI: 10.1007/10_2016_32] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Microbes are talented catalysts to synthesize valuable small molecules in their cytosol. However, to make full use of their skills - and that of metabolic engineers - the export of intracellularly synthesized molecules to the culture medium has to be considered. This step is as essential as is each step for the synthesis of the favorite molecule of the metabolic engineer, but is frequently not taken into account. To export small molecules via the microbial cell envelope, a range of different types of carrier proteins is recognized to be involved, which are primary active carriers, secondary active carriers, or proteins increasing diffusion. Relevant export may require just one carrier as is the case with L-lysine export by Corynebacterium glutamicum or involve up to four carriers as known for L-cysteine excretion by Escherichia coli. Meanwhile carriers for a number of small molecules of biotechnological interest are recognized, like for production of peptides, nucleosides, diamines, organic acids, or biofuels. In addition to carriers involved in amino acid excretion, such carriers and their impact on product formation are described, as well as the relatedness of export carriers which may serve as a hint to identify further carriers required to improve product formation by engineering export.
Collapse
|
43
|
Liu Q, Liang Y, Zhang Y, Shang X, Liu S, Wen J, Wen T. YjeH Is a Novel Exporter of l-Methionine and Branched-Chain Amino Acids in Escherichia coli. Appl Environ Microbiol 2015; 81:7753-66. [PMID: 26319875 PMCID: PMC4616930 DOI: 10.1128/aem.02242-15] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 08/25/2015] [Indexed: 01/01/2023] Open
Abstract
Amino acid efflux transport systems have important physiological functions and play vital roles in the fermentative production of amino acids. However, no methionine exporter has yet been identified in Escherichia coli. In this study, we identified a novel amino acid exporter, YjeH, in E. coli. The yjeH overexpression strain exhibited high tolerance to the structural analogues of l-methionine and branched-chain amino acids, decreased intracellular amino acid levels, and enhanced export rates in the presence of a Met-Met, Leu-Leu, Ile-Ile, or Val-Val dipeptide, suggesting that YjeH functions as an exporter of l-methionine and the three branched-chain amino acids. The export of the four amino acids in the yjeH overexpression strain was competitively inhibited in relation to each other. The expression of yjeH was strongly induced by increasing cytoplasmic concentrations of substrate amino acids. Green fluorescent protein (GFP)-tagged YjeH was visualized by total internal reflection fluorescence microscopy to confirm the plasma membrane localization of YjeH. Phylogenetic analysis of transporters indicated that YjeH belongs to the amino acid efflux family of the amino acid/polyamine/organocation (APC) superfamily. Structural modeling revealed that YjeH has the typical "5 + 5" transmembrane α-helical segment (TMS) inverted-repeat fold of APC superfamily transporters, and its binding sites are strictly conserved. The enhanced capacity of l-methionine export by the overexpression of yjeH in an l-methionine-producing strain resulted in a 70% improvement in titer. This study supplements the transporter classification and provides a substantial basis for the application of the methionine exporter in metabolic engineering.
Collapse
Affiliation(s)
- Qian Liu
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yong Liang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yun Zhang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xiuling Shang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Shuwen Liu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Jifu Wen
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China University of Chinese Academy of Sciences, Beijing, China
| | - Tingyi Wen
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
44
|
Abstract
This review considers the pathways for the degradation of amino acids and a few related compounds (agmatine, putrescine, ornithine, and aminobutyrate), along with their functions and regulation. Nitrogen limitation and an acidic environment are two physiological cues that regulate expression of several amino acid catabolic genes. The review considers Escherichia coli, Salmonella enterica serovar Typhimurium, and Klebsiella species. The latter is included because the pathways in Klebsiella species have often been thoroughly characterized and also because of interesting differences in pathway regulation. These organisms can essentially degrade all the protein amino acids, except for the three branched-chain amino acids. E. coli, Salmonella enterica serovar Typhimurium, and Klebsiella aerogenes can assimilate nitrogen from D- and L-alanine, arginine, asparagine, aspartate, glutamate, glutamine, glycine, proline, and D- and L-serine. There are species differences in the utilization of agmatine, citrulline, cysteine, histidine, the aromatic amino acids, and polyamines (putrescine and spermidine). Regardless of the pathway of glutamate synthesis, nitrogen source catabolism must generate ammonia for glutamine synthesis. Loss of glutamate synthase (glutamineoxoglutarate amidotransferase, or GOGAT) prevents utilization of many organic nitrogen sources. Mutations that create or increase a requirement for ammonia also prevent utilization of most organic nitrogen sources.
Collapse
|
45
|
Kim S, Ihara K, Katsube S, Hori H, Ando T, Isogai E, Yoneyama H. Characterization of the l-alanine exporter AlaE of Escherichia coli and its potential role in protecting cells from a toxic-level accumulation of l-alanine and its derivatives. Microbiologyopen 2015; 4:632-43. [PMID: 26073055 PMCID: PMC4554458 DOI: 10.1002/mbo3.269] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 04/21/2015] [Accepted: 05/04/2015] [Indexed: 11/14/2022] Open
Abstract
We previously reported that the alaE gene of Escherichia coli encodes the l-alanine exporter AlaE. The objective of this study was to elucidate the mechanism of the AlaE exporter. The minimum inhibitory concentration of l-alanine and l-alanyl-l-alanine in alaE-deficient l-alanine-nonmetabolizing cells MLA301ΔalaE was 4- and >4000-fold lower, respectively, than in the alaE-positive parent cells MLA301, suggesting that AlaE functions as an efflux pump to avoid a toxic-level accumulation of intracellular l-alanine and its derivatives. Furthermore, the growth of the alaE-deficient mutant derived from the l-alanine-metabolizing strain was strongly inhibited in the presence of a physiological level of l-alanyl-l-alanine. Intact MLA301ΔalaE and MLA301ΔalaE/pAlaE cells producing plasmid-borne AlaE, accumulated approximately 200% and 50%, respectively, of the [3H]l-alanine detected in MLA301 cells, suggesting that AlaE exports l-alanine. When 200 mmol/L l-alanine-loaded inverted membrane vesicles prepared from MLA301ΔalaE/pAlaE were placed in a solution containing 200 mmol/L or 0.34 μmol/L l-alanine, energy-dependent [3H]l-alanine accumulation occurred under either condition. This energy-dependent uphill accumulation of [3H]l-alanine was strongly inhibited in the presence of carbonyl cyanide m-chlorophenylhydrazone but not by dicyclohexylcarbodiimide, suggesting that the AlaE-mediated l-alanine extrusion was driven by proton motive force. Based on these results, physiological roles of the l-alanine exporter are discussed.
Collapse
Affiliation(s)
- Seryoung Kim
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 1-1, Amamiya-machi, Tsutsumidori, Aoba-ku, Sendai, 981-8555, Japan
| | - Kohei Ihara
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 1-1, Amamiya-machi, Tsutsumidori, Aoba-ku, Sendai, 981-8555, Japan
| | - Satoshi Katsube
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 1-1, Amamiya-machi, Tsutsumidori, Aoba-ku, Sendai, 981-8555, Japan
| | - Hatsuhiro Hori
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 1-1, Amamiya-machi, Tsutsumidori, Aoba-ku, Sendai, 981-8555, Japan
| | - Tasuke Ando
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 1-1, Amamiya-machi, Tsutsumidori, Aoba-ku, Sendai, 981-8555, Japan
| | - Emiko Isogai
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 1-1, Amamiya-machi, Tsutsumidori, Aoba-ku, Sendai, 981-8555, Japan
| | - Hiroshi Yoneyama
- Laboratory of Animal Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Science, Tohoku University, 1-1, Amamiya-machi, Tsutsumidori, Aoba-ku, Sendai, 981-8555, Japan
| |
Collapse
|
46
|
CysK Plays a Role in Biofilm Formation and Colonization by Vibrio fischeri. Appl Environ Microbiol 2015; 81:5223-34. [PMID: 26025891 DOI: 10.1128/aem.00157-15] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 05/19/2015] [Indexed: 11/20/2022] Open
Abstract
A biofilm, or a matrix-embedded community of cells, promotes the ability of the bacterium Vibrio fischeri to colonize its symbiotic host, the Hawaiian squid Euprymna scolopes. Biofilm formation and colonization depend on syp, an 18-gene polysaccharide locus. To identify other genes necessary for biofilm formation, we screened for mutants that failed to form wrinkled colonies, a type of biofilm. We obtained several with defects in genes required for cysteine metabolism, including cysH, cysJ, cysK, and cysN. The cysK mutant exhibited the most severe wrinkling defect. It could be complemented with a wild-type copy of the cysK gene, which encodes O-acetylserine sulfhydrolase, or by supplementing the medium with additional cysteine. None of a number of other mutants defective for biosynthetic genes negatively impacted wrinkled colony formation, suggesting a specific role for CysK. CysK did not appear to control activation of Syp regulators or transcription of the syp locus, but it did influence production of the Syp polysaccharide. Under biofilm-inducing conditions, the cysK mutant retained the same ability as that of the parent strain to adhere to the agar surface. The cysK mutant also exhibited a defect in pellicle production that could be complemented by the cysK gene but not by cysteine, suggesting that, under these conditions, CysK is important for more than the production of cysteine. Finally, our data reveal a role for cysK in symbiotic colonization by V. fischeri. Although many questions remain, this work provides insights into additional factors required for biofilm formation and colonization by V. fischeri.
Collapse
|
47
|
Holyoake LV, Poole RK, Shepherd M. The CydDC Family of Transporters and Their Roles in Oxidase Assembly and Homeostasis. Adv Microb Physiol 2015. [PMID: 26210105 DOI: 10.1016/bs.ampbs.2015.04.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The CydDC complex of Escherichia coli is a heterodimeric ATP-binding cassette type transporter (ABC transporter) that exports the thiol-containing redox-active molecules cysteine and glutathione. These reductants are thought to aid redox homeostasis of the periplasm, permitting correct disulphide folding of periplasmic and secreted proteins. Loss of CydDC results in the periplasm becoming more oxidising and abolishes the assembly of functional bd-type respiratory oxidases that couple the oxidation of ubiquinol to the reduction of oxygen to water. In addition, CydDC-mediated redox control is important for haem ligation during cytochrome c assembly. Given the diverse roles for CydDC in redox homeostasis, respiratory metabolism and the maturation of virulence factors, this ABC transporter is an intriguing system for researchers interested in both the physiology of redox perturbations and the role of low-molecular-weight thiols during infection.
Collapse
|
48
|
Yamamoto K, Nonaka G, Ozawa T, Takumi K, Ishihama A. Induction of the Escherichia coli yijE gene expression by cystine. Biosci Biotechnol Biochem 2014; 79:218-22. [PMID: 25346166 DOI: 10.1080/09168451.2014.972328] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Cystine is formed from two molecules of the cysteine under oxidized conditions, but is reversibly converted to cysteine by reduction. Growth of Escherichia coli is retarded in the presence of excess cystine. Transcriptome analysis showed 11 up-regulated and 26 down-regulated genes upon exposure to excess cystine. The reporter assay confirmed regulation by cystine of the expression of one up-regulated membrane gene, yijE, and two down-regulated membrane genes, yhdT and yihN. In order to identify the as yet unidentified gene encoding cystine efflux transporter, the putative cystine efflux candidate, yijE gene, was over-expressed. Expression of the yijE gene suppressed the slow growth of E. coli in the presence of high concentration of extracellular cystine. In good agreement, the knock-out of yijE gene increased the sensibility to cystine. These observations altogether imply that the yijE gene is involved in response to cystine in E. coli.
Collapse
Affiliation(s)
- Kaneyoshi Yamamoto
- a Department of Frontier Bioscience and Research Center for Micro-Nano Technology , Hosei University , Koganei , Japan
| | | | | | | | | |
Collapse
|
49
|
Deutch C, Spahija I, Wagner C. Susceptibility of Escherichia coli
to the toxic L-proline analogue L-selenaproline is dependent on two L-cystine transport systems. J Appl Microbiol 2014; 117:1487-99. [PMID: 25139244 DOI: 10.1111/jam.12623] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 08/11/2014] [Accepted: 08/14/2014] [Indexed: 11/30/2022]
Affiliation(s)
- C.E. Deutch
- School of Mathematical and Natural Sciences; Arizona State University at the West Campus; Phoenix AZ USA
| | - I. Spahija
- School of Mathematical and Natural Sciences; Arizona State University at the West Campus; Phoenix AZ USA
| | - C.E. Wagner
- School of Mathematical and Natural Sciences; Arizona State University at the West Campus; Phoenix AZ USA
| |
Collapse
|
50
|
Yamashita M, Shepherd M, Booth WI, Xie H, Postis V, Nyathi Y, Tzokov SB, Poole RK, Baldwin SA, Bullough PA. Structure and function of the bacterial heterodimeric ABC transporter CydDC: stimulation of ATPase activity by thiol and heme compounds. J Biol Chem 2014; 289:23177-23188. [PMID: 24958725 PMCID: PMC4132815 DOI: 10.1074/jbc.m114.590414] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In Escherichia coli, the biogenesis of both cytochrome bd-type quinol oxidases and periplasmic cytochromes requires the ATP-binding cassette-type cysteine/GSH transporter, CydDC. Recombinant CydDC was purified as a heterodimer and found to be an active ATPase both in soluble form with detergent and when reconstituted into a lipid environment. Two-dimensional crystals of CydDC were analyzed by electron cryomicroscopy, and the protein was shown to be made up of two non-identical domains corresponding to the putative CydD and CydC subunits, with dimensions characteristic of other ATP-binding cassette transporters. CydDC binds heme b. Detergent-solubilized CydDC appears to adopt at least two structural states, each associated with a characteristic level of bound heme. The purified protein in detergent showed a weak basal ATPase activity (approximately 100 nmol Pi/min/mg) that was stimulated ∼3-fold by various thiol compounds, suggesting that CydDC could act as a thiol transporter. The presence of heme (either intrinsic or added in the form of hemin) led to a further enhancement of thiol-stimulated ATPase activity, although a large excess of heme inhibited activity. Similar responses of the ATPase activity were observed with CydDC reconstituted into E. coli lipids. These results suggest that heme may have a regulatory role in CydDC-mediated transmembrane thiol transport.
Collapse
Affiliation(s)
- Masao Yamashita
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom and
| | - Mark Shepherd
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom and
| | - Wesley I Booth
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom and
| | - Hao Xie
- School of Biomedical Sciences, The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Vincent Postis
- School of Biomedical Sciences, The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Yvonne Nyathi
- School of Biomedical Sciences, The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Svetomir B Tzokov
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom and
| | - Robert K Poole
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom and
| | - Stephen A Baldwin
- School of Biomedical Sciences, The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Per A Bullough
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom and.
| |
Collapse
|