1
|
Long DR, Holmes EA, Lo HY, Penewit K, Almazan J, Hodgson T, Berger NF, Bishop ZH, Lewis JD, Waalkes A, Wolter DJ, Salipante SJ. Clinical and in vitro models identify distinct adaptations enhancing Staphylococcus aureus pathogenesis in human macrophages. PLoS Pathog 2024; 20:e1012394. [PMID: 38991026 DOI: 10.1371/journal.ppat.1012394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 07/04/2024] [Indexed: 07/13/2024] Open
Abstract
Staphylococcus aureus is a facultative intracellular pathogen of human macrophages, which facilitates chronic infection. The genotypes, pathways, and mutations influencing that phenotype remain incompletely explored. Here, we used two distinct strategies to ascertain S. aureus gene mutations affecting pathogenesis in macrophages. First, we analyzed isolates collected serially from chronic cystic fibrosis (CF) respiratory infections. We found that S. aureus strains evolved greater macrophage invasion capacity during chronic human infection. Bacterial genome-wide association studies (GWAS) identified 127 candidate genes for which mutation was significantly associated with macrophage pathogenesis in vivo. In parallel, we passaged laboratory S. aureus strains in vitro to select for increased infection of human THP-1 derived macrophages, which identified 15 candidate genes by whole-genome sequencing. Functional validation of candidate genes using isogenic transposon mutant knockouts and CRISPR interference (CRISPRi) knockdowns confirmed virulence contributions from 37 of 39 tested genes (95%) implicated by in vivo studies and 7 of 10 genes (70%) ascertained from in vitro selection, with one gene in common to the two strategies. Validated genes included 17 known virulence factors (39%) and 27 newly identified by our study (61%), some encoding functions not previously associated with macrophage pathogenesis. Most genes (80%) positively impacted macrophage invasion when disrupted, consistent with the phenotype readily arising from loss-of-function mutations in vivo. This work reveals genes and mechanisms that contribute to S. aureus infection of macrophages, highlights differences in mutations underlying convergent phenotypes arising from in vivo and in vitro systems, and supports the relevance of S. aureus macrophage pathogenesis during chronic respiratory infection in CF. Additional studies will be needed to illuminate the exact mechanisms by which implicated mutations affect their phenotypes.
Collapse
Affiliation(s)
- Dustin R Long
- Division of Critical Care Medicine, Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Elizabeth A Holmes
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Hsin-Yu Lo
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Kelsi Penewit
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Jared Almazan
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Taylor Hodgson
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Nova F Berger
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Zoe H Bishop
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Janessa D Lewis
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Adam Waalkes
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Daniel J Wolter
- Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Stephen J Salipante
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| |
Collapse
|
2
|
Mordukhova EA, Kim J, Jin H, No KT, Pan JG. The efficacy of the food-grade antimicrobial xanthorrhizol against Staphylococcus aureus is associated with McsL channel expression. Front Microbiol 2024; 15:1439009. [PMID: 39021623 PMCID: PMC11251944 DOI: 10.3389/fmicb.2024.1439009] [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: 05/27/2024] [Accepted: 06/18/2024] [Indexed: 07/20/2024] Open
Abstract
Background The emergence and spread of multidrug-resistant Staphylococcus aureus strains demonstrates the urgent need for new antimicrobials. Xanthorrhizol, a plant-derived sesquiterpenoid compound, has a rapid killing effect on methicillin-susceptible strains and methicillin-resistant strains of S. aureus achieving the complete killing of staphylococcal cells within 2 min using 64 μg/mL xanthorrhizol. However, the mechanism of its action is not yet fully understood. Methods The S. aureus cells treated with xanthorrhizol were studied using optical diffraction tomography. Activity of xanthorrhizol against the wild-type and mscL null mutant of S. aureus ATCC 29213 strain was evaluated in the time-kill assay. Molecular docking was conducted to predict the binding of xanthorrhizol to the SaMscL protein. Results Xanthorrhizol treatment of S. aureus cells revealed a decrease in cell volume, dry weight, and refractive index (RI), indicating efflux of the cell cytoplasm, which is consistent with the spontaneous activation of the mechanosensitive MscL channel. S. aureus ATCC 29213ΔmscL was significantly more resistant to xanthorrhizol than was the wild-type strain. Xanthorrhizol had an enhanced inhibitory effect on the growth and viability of exponentially growing S. aureus ATCC 29213ΔmscL cells overexpressing the SaMscL protein and led to a noticeable decrease in their viability in the stationary growth phase. The amino acid residues F5, V14, M23, A79, and V84 were predicted to be the residues of the binding pocket for xanthorrhizol. We also showed that xanthorrhizol increased the efflux of solutes such as K+ and glutamate from S. aureus ATCC 29213ΔmscL cells overexpressing SaMscL. Xanthorrhizol enhanced the antibacterial activity of the antibiotic dihydrostreptomycin, which targets the MscL protein. Conclusion Our findings indicate that xanthorrhizol targets the SaMscL protein in S. aureus cells and may have important implications for the development of a safe antimicrobial agent.
Collapse
Affiliation(s)
| | - Jongwan Kim
- Bioinformatics and Molecular Design Research Center (BMDRC), Incheon, Republic of Korea
| | - Haiyan Jin
- The Interdisciplinary Graduate Program in Integrative Biotechnology and Translational Medicine, Yonsei University, Incheon, Republic of Korea
| | - Kyoung Tai No
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Jae-Gu Pan
- GenoFocus Ltd., Daejeon, Republic of Korea
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Republic of Korea
| |
Collapse
|
3
|
Trognon J, Rima M, Lajoie B, Roques C, El Garah F. NaCl-induced modulation of species distribution in a mixed P. aeruginosa / S. aureus / B.cepacia biofilm. Biofilm 2023; 6:100153. [PMID: 37711514 PMCID: PMC10497989 DOI: 10.1016/j.bioflm.2023.100153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/30/2023] [Accepted: 08/31/2023] [Indexed: 09/16/2023] Open
Abstract
Pseudomonas aeruginosa, Staphylococcus aureus, and Burkholderia cepacia are notorious pathogens known for their ability to form resilient biofilms, particularly within the lung environment of cystic fibrosis (CF) patients. The heightened concentration of NaCl, prevalent in the airway liquid of CF patients' lungs, has been identified as a factor that promotes the growth of osmotolerant bacteria like S. aureus and dampens host antibacterial defenses, thereby fostering favorable conditions for infections. In this study, we aimed to investigate how increased NaCl concentrations impact the development of multi-species biofilms in vitro, using both laboratory strains and clinical isolates of P. aeruginosa, S. aureus, and B. cepacia co-cultures. Employing a low-nutrient culture medium that fosters biofilm growth of the selected species, we quantified biofilm formation through a combination of adherent CFU counts, qPCR analysis, and confocal microscopy observations. Our findings reaffirmed the challenges faced by S. aureus in establishing growth within 1:1 mixed biofilms with P. aeruginosa when cultivated in a minimal medium. Intriguingly, at an elevated NaCl concentration of 145 mM, a symbiotic relationship emerged between S. aureus and P. aeruginosa, enabling their co-existence. Notably, this hyperosmotic environment also exerted an influence on the interplay of these two bacteria with B. cepacia. We demonstrated that elevated NaCl concentrations play a pivotal role in orchestrating the distribution of these three species within the biofilm matrix. Furthermore, our study unveiled the beneficial impact of NaCl on the biofilm growth of clinically relevant mucoid P. aeruginosa strains, as well as two strains of methicillin-sensitive and methicillin-resistant S. aureus. This underscores the crucial role of the microenvironment during the colonization and infection processes. The results suggest that hyperosmotic conditions could hold the key to unlocking a deeper understanding of the genesis and behavior of CF multi-species biofilms.
Collapse
Affiliation(s)
- Jeanne Trognon
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Maya Rima
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Barbora Lajoie
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Christine Roques
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
- CHU Toulouse, Hôpital Purpan, Service de Bactériologie Hygiène, Toulouse, France
| | - Fatima El Garah
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| |
Collapse
|
4
|
Guan P, Chang Y, Li S, Wang X, Dong Z, Zhou W, Zheng Q, Huang Z, Suo B. Transcriptome analysis reveals the molecular mechanism of cinnamaldehyde against Bacillus cereus spores in ready-to-eat beef. Food Res Int 2023; 163:112185. [PMID: 36596126 DOI: 10.1016/j.foodres.2022.112185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/04/2022] [Accepted: 11/15/2022] [Indexed: 11/21/2022]
Abstract
The purpose of this study was to investigate the antibacterial effect and mechanism of cinnamaldehyde on Bacillus cereus spores in ready-to-eat beef. The colour difference and texture of the ready-to-eat beef supplemented with cinnamaldehyde did not differ greatly from the colour and texture of the blank beef. However, cinnamaldehyde has an effective antibacterial effect on the total number of bacterial colonies and B. cereus spores in ready-to-eat beef. Transmission electron microscopy (TEM) analysis revealed that the cell membrane of B. cereus was disrupted by cinnamaldehyde, leading to leakage of intracellular components. Transcriptome sequencing (RNA-seq) indicated that the B. cereus spore resistance regulation system (sigB, sigW, rsbW, rsbV, yfkM and yflT) and phosphoenolpyruvate phosphotransferase system (PTS) (ptsH, ptsI and ptsG) respond positively to cinnamaldehyde in an adverse environment. Intracellular disorders due to damage to the cell membrane involve some transporters (copA, opuBA and opuD) and some oxidative stress systems (ywrO, scdA and katE) in the regulation of the body. However, downregulation of K+ transport channels (kdpD and kdpB), osmotic pressure regulation (opuE) and some oxidative stress (norR and srrA)-related genes may accelerate spore apoptosis. In addition, cinnamaldehyde also effectively inhibits the spore germination-related genes (smc, mreB and gerE). This study provides new insights into the molecular mechanism of the antibacterial effect of cinnamaldehyde on B. cereus spores in ready-to-eat beef.
Collapse
Affiliation(s)
- Peng Guan
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China
| | - Yuting Chang
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China
| | - Sen Li
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China
| | - Xiaojie Wang
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Staple Grain Processing, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; National R&D Center for Frozen Rice & Wheat Products Processing Technology, Henan Engineering Laboratory of Quick-Frozen Flour-Rice Food and Prepared Food, Henan Agricultural University, Zhengzhou, China
| | - Zijie Dong
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China
| | - Weitao Zhou
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China
| | - Qi Zheng
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China
| | - Zhongmin Huang
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Staple Grain Processing, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; National R&D Center for Frozen Rice & Wheat Products Processing Technology, Henan Engineering Laboratory of Quick-Frozen Flour-Rice Food and Prepared Food, Henan Agricultural University, Zhengzhou, China
| | - Biao Suo
- College of Food Science and Technology, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Staple Grain Processing, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; National R&D Center for Frozen Rice & Wheat Products Processing Technology, Henan Engineering Laboratory of Quick-Frozen Flour-Rice Food and Prepared Food, Henan Agricultural University, Zhengzhou, China.
| |
Collapse
|
5
|
Proline Transport and Growth Changes in Proline Transport Mutants of Staphylococcus aureus. Microorganisms 2022; 10:microorganisms10101888. [DOI: 10.3390/microorganisms10101888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 11/16/2022] Open
Abstract
Staphylococcus aureus is a major cause of skin/soft tissue infections and more serious infections in humans. The species usually requires the importation of proline to be able to survive. Previous work has shown that single mutations in genes that encode for proline transporters affect the ability of S. aureus to survive in vitro and in vivo. To better understand proline transport in S. aureus, double and triple gene mutant strains were created that targeted the opuD, proP, and putP genes. Single gene mutants had some effect on proline transport, whereas double mutants exhibited significantly lower proline transport. An opuD prop putP triple gene mutant displayed the lowest proline transport under low- and high-affinity conditions. To assess growth differences caused by the mutations, the same mutants were grown in brain heart infusion (BHI) broth and defined staphylococcal medium (DSM) with various concentrations of proline. The triple mutant did not grow in DSM with a low concentration of proline and grew poorly in both DSM with a high proline concentration and BHI broth. These results show that S. aureus has multiple mechanisms to import proline into the cell and knocking out three of the main proline transporters significantly hinders S. aureus growth.
Collapse
|
6
|
Role of Staphylococcus aureus Tet38 in Transport of Tetracycline and Its Regulation in a Salt Stress Environment. J Bacteriol 2022; 204:e0014222. [PMID: 35699453 DOI: 10.1128/jb.00142-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus Tet38 efflux pump has multiple functions, including conferring resistance to tetracycline and other compounds and enabling internalization and survival within epithelial cells. In this study, we evaluated the effects of sodium and potassium on tet38 expression. These monovalent cations are known to play a role in transport by the related S. aureus TetK and B. subtilis TetL transporters. tet38 transcription decreased with increasing sodium concentrations by means of direct repression by the salt stress-dependent KdpD/E regulator. tet38 transcription increased 20-fold and tetracycline minimum inhibitory concentration (MIC) increased 4-fold in a ΔkdpD mutant. KdpE bound specifically to the tet38 promoter. Under extreme salt stress, the survival of S. aureus with intact tet38 was reduced compared to that of a Δtet38 mutant. To study the effect of sodium on Tet38 function, we generated constructs overexpressing tet38 and tetK and introduced them into Escherichia coli TO114, which is deficient in major sodium transporters. Tet38 tetracycline efflux was directly demonstrated in a fluorescence assay, and tetracycline efflux of both Tet38 and TetK was abolished by the protonophore carbonyl cyanide 3-chlorophenylhydrazone (CCCP). In contrast, NaCl inhibited efflux by Tet38 but not TetK, whereas KCl inhibited efflux by TetK but not Tet38. Cell-associated Na increased with heterologous overexpression of Tet38. These data indicate that S. aureus Tet38 is a tetracycline efflux pump regulated by the KdpD/E regulator. Under salt stress, S. aureus adjusted its survival in part by reducing the expression of tet38 through KdpD/E. The mechanisms by which Tet38 is detrimental to salt tolerance in S. aureus and inhibited by sodium remain to be determined. IMPORTANCE This study shows that S. aureus Tet38 is a tetracycline efflux pump regulated by KdpD/E regulator. These findings are the first direct demonstration of Tet38-mediated tetracycline efflux, which had previously been inferred from its ability to confer tetracycline resistance. Under salt stress, S. aureus adjusts its survival in part by reducing the expression of tet38 through KdpD/E. We demonstrated the differences in the respective functions of S. aureus Tet38 and other tetracycline efflux transporters (S. aureus TetK, B. subtilis TetL) regarding their transport of tetracycline and Na+/K+. Notably, sodium selectively reduced tetracycline efflux by Tet38, and potassium selectively reduced tetracycline efflux by TetK. The multiple functions of Tet38 emphasize its importance in bacterial adaptation to and survival in diverse environments.
Collapse
|
7
|
Weaver AJ, Borgogna TR, O’Shea-Stone G, Peters TR, Copié V, Voyich J, Teintze M. 18β-Glycyrrhetinic Acid Induces Metabolic Changes and Reduces Staphylococcus aureus Bacterial Cell-to-Cell Interactions. Antibiotics (Basel) 2022; 11:antibiotics11060781. [PMID: 35740189 PMCID: PMC9220049 DOI: 10.3390/antibiotics11060781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/02/2022] [Accepted: 06/07/2022] [Indexed: 12/04/2022] Open
Abstract
The rise in bacterial resistance to common antibiotics has raised an increased need for alternative treatment strategies. The natural antibacterial product, 18β-glycyrrhetinic acid (GRA) has shown efficacy against community-associated methicillin-resistant Staphylococcus aureus (MRSA), although its interactions against planktonic and biofilm modes of growth remain poorly understood. This investigation utilized biochemical and metabolic approaches to further elucidate the effects of GRA on MRSA. Prolonged exposure of planktonic MRSA cell cultures to GRA resulted in increased production of staphyloxanthin, a pigment known to exhibit antioxidant and membrane-stabilizing functions. Then, 1D 1H NMR analyses of intracellular metabolite extracts from MRSA treated with GRA revealed significant changes in intracellular polar metabolite profiles, including increased levels of succinate and citrate, and significant reductions in several amino acids, including branch chain amino acids. These changes reflect the MRSA response to GRA exposure, including potentially altering its membrane composition, which consumes branched chain amino acids and leads to significant energy expenditure. Although GRA itself had no significant effect of biofilm viability, it seems to be an effective biofilm disruptor. This may be related to interference with cell–cell aggregation, as treatment of planktonic MRSA cultures with GRA leads to a significant reduction in micro-aggregation. The dispersive nature of GRA on MRSA biofilms may prove valuable for treatment of such infections and could be used to increase susceptibility to complementary antibiotic therapeutics.
Collapse
Affiliation(s)
- Alan J. Weaver
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA; (A.J.W.J.); (G.O.-S.); (T.R.P.)
| | - Timothy R. Borgogna
- Department of Microbiology & Cell Biology, Montana State University, Bozeman, MT 59717, USA;
| | - Galen O’Shea-Stone
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA; (A.J.W.J.); (G.O.-S.); (T.R.P.)
| | - Tami R. Peters
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA; (A.J.W.J.); (G.O.-S.); (T.R.P.)
| | - Valérie Copié
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA; (A.J.W.J.); (G.O.-S.); (T.R.P.)
- Correspondence: (V.C.); (J.V.); (M.T.); Tel.: +406-994-7244 (V.C.); +406-994-7184 (J.V.); +406-994-6515 (M.T.)
| | - Jovanka Voyich
- Department of Microbiology & Cell Biology, Montana State University, Bozeman, MT 59717, USA;
- Correspondence: (V.C.); (J.V.); (M.T.); Tel.: +406-994-7244 (V.C.); +406-994-7184 (J.V.); +406-994-6515 (M.T.)
| | - Martin Teintze
- Department of Chemistry & Biochemistry, Montana State University, Bozeman, MT 59717, USA; (A.J.W.J.); (G.O.-S.); (T.R.P.)
- Correspondence: (V.C.); (J.V.); (M.T.); Tel.: +406-994-7244 (V.C.); +406-994-7184 (J.V.); +406-994-6515 (M.T.)
| |
Collapse
|
8
|
Michel AM, Borrero-de Acuña JM, Molinari G, Ünal CM, Will S, Derksen E, Barthels S, Bartram W, Schrader M, Rohde M, Zhang H, Hoffmann T, Neumann-Schaal M, Bremer E, Jahn D. Cellular adaptation of Clostridioides difficile to high salinity encompasses a compatible solute-responsive change in cell morphology. Environ Microbiol 2022; 24:1499-1517. [PMID: 35106888 DOI: 10.1111/1462-2920.15925] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/27/2022]
Abstract
Infections by the pathogenic gut bacterium Clostridioides difficile cause severe diarrheas up to a toxic megacolon and are currently among the major causes of lethal bacterial infections. Successful bacterial propagation in the gut is strongly associated with the adaptation to changing nutrition-caused environmental conditions; e.g. environmental salt stresses. Concentrations of 350 mM NaCl, the prevailing salinity in the colon, led to significantly reduced growth of C. difficile. Metabolomics of salt- stressed bacteria revealed a major reduction of the central energy generation pathways, including the Stickland-fermentation reactions. No obvious synthesis of compatible solutes was observed up to 24 h of growth. The ensuing limited tolerance to high salinity and absence of compatible solute synthesis might result from an evolutionary adaptation to the exclusive life of C. difficile in the mammalian gut. Addition of the compatible solutes carnitine, glycine-betaine, γ-butyrobetaine, crotonobetaine, homobetaine, proline-betaine and dimethylsulfoniopropionate (DMSP) restored growth (choline and proline failed) under conditions of high salinity. A bioinformatically-identified OpuF-type ABC-transporter imported most of the used compatible solutes. A long-term adaptation after 48 h included a shift of the Stickland fermentation-based energy metabolism from the utilization to the accumulation of L-proline and resulted in restored growth. Surprisingly, salt stress resulted in the formation of coccoid C. difficile cells instead of the typical rod-shaped cells, a process reverted by the addition of several compatible solutes. Hence, compatible solute import via OpuF is the major immediate adaptation strategy of C. difficile to high salinity-incurred cellular stress. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Annika-Marisa Michel
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - José Manuel Borrero-de Acuña
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany.,Universidad de Sevilla, Facultad de Biología, Departamento de Microbiología, Av. de la Reina Mercedes, n° 6, CP, 41012, Sevilla, Spain
| | - Gabriella Molinari
- Central Facility for Microscopy, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Can Murat Ünal
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Sabine Will
- Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Elisabeth Derksen
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Stefan Barthels
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - Wiebke Bartram
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| | - Michel Schrader
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Hao Zhang
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,School of Life Science and Technology, Changchun University of Science and Technology, No. 7186 Weixing Road, 130022, Changchun, China
| | - Tamara Hoffmann
- Laboratory for Microbiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany.,Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany
| | - Meina Neumann-Schaal
- Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany.,Leibniz-Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Erhard Bremer
- Laboratory for Microbiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany.,Center for Synthetic Microbiology (SYNMIKRO), Philipps-Universität Marburg, Marburg, Germany
| | - Dieter Jahn
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Braunschweig Integrated Centre of Systems Biology (BRICS), Technische Universität Braunschweig, Braunschweig, Germany
| |
Collapse
|
9
|
Joshi C, Kothari V. Bacterial Stress-response Machinery as a Target for Next-generation Antimicrobials. Infect Disord Drug Targets 2022; 22:e210322202493. [PMID: 35319398 DOI: 10.2174/1871526522666220321153332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 10/30/2021] [Accepted: 12/29/2021] [Indexed: 06/14/2023]
Affiliation(s)
- Chinmayi Joshi
- Smt. S.S.Patel Nootan Science and Commerce College, Sankalchand Patel University, Visnagar 384315, India
| | - Vijay Kothari
- Institute of Science, Nirma University, Ahmedabad 382481, India
| |
Collapse
|
10
|
Tikariha H, Pavagadhi S, Mayalagu S, Poh MCH, Swarup S. Hybrid Genome Assembly for Predicting Functional Potential of a Novel Streptomyces Strain as Plant Biomass Valorisation Agent. Indian J Microbiol 2021; 61:283-290. [PMID: 34294994 DOI: 10.1007/s12088-021-00935-5] [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: 12/30/2020] [Accepted: 03/27/2021] [Indexed: 11/27/2022] Open
Abstract
Environmental bioremediation relies heavily on the realized potential of efficient bioremediation agents or microbial strains of interest. Identifying suitable microbial agents for plant biomass waste valorization requires (i) high-quality genome assemblies to predict the full metabolic and functional potential, (ii) accurate mapping of lignocellulose metabolizing enzymes. However, fragmented nature of the sequenced genomes often limits the prediction ability due to breaks occurring in coding sequences. To address these challenges and as part of our ongoing agri-culturomics efforts, we have performed a hybrid genome assembly using Illumina and Nanopore reads with modified assembly protocol, for a novel Streptomyces strain isolated from the rhizosphere niche of green leafy vegetables grown in a commercial urban farm. High-quality genome was assembled with the size of 8.6 Mb in just two contigs with N50 of 8,542,030 and coverage of 383X. This facilitated identification and complete arrangement of approximately 248 CAZymes and 38 biosynthetic gene clusters in the genome. Multiple gene clusters consisting of cellulases and hemicellulases associated with substrate recognition domain were identified in the genome. Genes for lignin, chitin, and even some aromatic compounds degradation were found in the Streptomyces sp. genome which makes it a promising candidate for lignocellulosic waste valorization. Supplementary Information The online version contains supplementary material available at 10.1007/s12088-021-00935-5.
Collapse
Affiliation(s)
- Hitesh Tikariha
- NUS Environmental Research Institute, National University of Singapore, Singapore, 117411 Singapore
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, 117456 Singapore
| | - Shruti Pavagadhi
- NUS Environmental Research Institute, National University of Singapore, Singapore, 117411 Singapore
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, 117456 Singapore
| | - Sevugan Mayalagu
- NUS Environmental Research Institute, National University of Singapore, Singapore, 117411 Singapore
| | - Miko Chin Hong Poh
- NUS Environmental Research Institute, National University of Singapore, Singapore, 117411 Singapore
| | - Sanjay Swarup
- NUS Environmental Research Institute, National University of Singapore, Singapore, 117411 Singapore
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, 117456 Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, 117558 Singapore
| |
Collapse
|