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Warneke R, Herzberg C, Daniel R, Hormes B, Stülke J. Control of three-carbon amino acid homeostasis by promiscuous importers and exporters in Bacillus subtilis: role of the "sleeping beauty" amino acid exporters. mBio 2024; 15:e0345623. [PMID: 38470260 PMCID: PMC11005379 DOI: 10.1128/mbio.03456-23] [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: 12/19/2023] [Accepted: 02/13/2024] [Indexed: 03/13/2024] Open
Abstract
The Gram-positive model bacterium Bacillus subtilis can acquire amino acids by import, de novo biosynthesis, or degradation of proteins and peptides. The accumulation of several amino acids inhibits the growth of B. subtilis, probably due to misincorporation into cellular macromolecules such as proteins or peptidoglycan or due to interference with other amino acid biosynthetic pathways. Here, we studied the adaptation of B. subtilis to toxic concentrations of the three-carbon amino acids L-alanine, β-alanine, and 2,3-diaminopropionic acid, as well as the two-carbon amino acid glycine. Resistance to the non-proteinogenic amino acid β-alanine, which is a precursor for coenzyme A biosynthesis, is achieved by mutations that either activate a cryptic amino acid exporter, AexA (previously YdeD), or inactivate the amino acid importers AimA, AimB (previously YbxG), and BcaP. The aexA gene is very poorly expressed under most conditions studied. However, mutations affecting the transcription factor AerA (previously YdeC) can result in strong constitutive aexA expression. AexA is the first characterized member of a group of amino acid exporters in B. subtilis, which are all very poorly expressed. Therefore, we suggest to call this group "sleeping beauty amino acid exporters." 2,3-Diaminopropionic acid can also be exported by AexA, and this amino acid also seems to be a natural substrate of AerA/AexA, as it can cause a slight but significant induction of aexA expression, and AexA also provides some natural resistance toward 2,3-diaminopropionic acid. Moreover, our work shows how low-specificity amino acid transporters contribute to amino acid homeostasis in B. subtilis.IMPORTANCEEven though Bacillus subtilis is one of the most-studied bacteria, amino acid homeostasis in this organism is not fully understood. We have identified import and export systems for the C2 and C3 amino acids. Our work demonstrates that the responsible amino acid permeases contribute in a rather promiscuitive way to amino acid uptake. In addition, we have discovered AexA, the first member of a group of very poorly expressed amino acid exporters in B. subtilis that we call "sleeping beauty amino acid exporters." The expression of these transporters is typically triggered by mutations in corresponding regulator genes that are acquired upon exposure to toxic amino acids. These exporters are ubiquitous in all domains of life. It is tempting to speculate that many of them are not expressed until the cells experience selective pressure by toxic compounds, and they protect the cells from rare but potentially dangerous encounters with such compounds.
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Affiliation(s)
- Robert Warneke
- Department of General Microbiology, Institute for Microbiology and Genetics, GZMB, Georg-August-University, Göttingen, Germany
| | - Christina Herzberg
- Department of General Microbiology, Institute for Microbiology and Genetics, GZMB, Georg-August-University, Göttingen, Germany
| | - Richard Daniel
- Center for Bacterial Cell Biology, Biosciences Institute, Medical Faculty, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Björn Hormes
- Department of General Microbiology, Institute for Microbiology and Genetics, GZMB, Georg-August-University, Göttingen, Germany
| | - Jörg Stülke
- Department of General Microbiology, Institute for Microbiology and Genetics, GZMB, Georg-August-University, Göttingen, Germany
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2
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Meißner J, Königshof M, Wrede K, Warneke R, Mardoukhi MSY, Commichau FM, Stülke J. Control of asparagine homeostasis in Bacillus subtilis: identification of promiscuous amino acid importers and exporters. J Bacteriol 2024; 206:e0042023. [PMID: 38193659 PMCID: PMC10882977 DOI: 10.1128/jb.00420-23] [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: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 01/10/2024] Open
Abstract
The Gram-positive model bacterium B. subtilis is able to import all proteinogenic amino acids from the environment as well as to synthesize them. However, the players involved in the acquisition of asparagine have not yet been identified for this bacterium. In this work, we used d-asparagine as a toxic analog of l-asparagine to identify asparagine transporters. This revealed that d- but not l-asparagine is taken up by the malate/lactate antiporter MleN. Specific strains that are sensitive to the presence of l-asparagine due to the lack of the second messenger cyclic di-AMP or due to the intracellular accumulation of this amino acid were used to isolate and characterize suppressor mutants that were resistant to the presence of otherwise growth-inhibiting concentrations of l-asparagine. These screens identified the broad-spectrum amino acid importers AimA and BcaP as responsible for the acquisition of l-asparagine. The amino acid exporter AzlCD allows detoxification of l-asparagine in addition to 4-azaleucine and histidine. This work supports the idea that amino acids are often transported by promiscuous importers and exporters. However, our work also shows that even stereo-enantiomeric amino acids do not necessarily use the same transport systems.IMPORTANCETransport of amino acid is a poorly studied function in many bacteria, including the model organism Bacillus subtilis. The identification of transporters is hampered by the redundancy of transport systems for most amino acids as well as by the poor specificity of the transporters. Here, we apply several strategies to use the growth-inhibitive effect of many amino acids under defined conditions to isolate suppressor mutants that exhibit either reduced uptake or enhanced export of asparagine, resulting in the identification of uptake and export systems for l-asparagine. The approaches used here may be useful for the identification of transporters for other amino acids both in B. subtilis and in other bacteria.
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Affiliation(s)
- Janek Meißner
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Manuel Königshof
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Katrin Wrede
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Robert Warneke
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | | | - Fabian M. Commichau
- FG Molecular Microbiology, Institute for Biology, University of Hohenheim, Stuttgart, Germany
| | - Jörg Stülke
- Department of General Microbiology, Institute for Microbiology & Genetics, GZMB, Georg-August-University Göttingen, Göttingen, Germany
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3
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Li XY, Zeng ZX, Cheng ZX, Wang YL, Yuan LJ, Zhai ZY, Gong W. Common pathogenic bacteria-induced reprogramming of the host proteinogenic amino acids metabolism. Amino Acids 2023; 55:1487-1499. [PMID: 37814028 PMCID: PMC10689525 DOI: 10.1007/s00726-023-03334-w] [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: 04/02/2023] [Accepted: 09/12/2023] [Indexed: 10/11/2023]
Abstract
Apart from cancer, metabolic reprogramming is also prevalent in other diseases, such as bacterial infections. Bacterial infections can affect a variety of cells, tissues, organs, and bodies, leading to a series of clinical diseases. Common Pathogenic bacteria include Helicobacter pylori, Salmonella enterica, Mycobacterium tuberculosis, Staphylococcus aureus, and so on. Amino acids are important and essential nutrients in bacterial physiology and support not only their proliferation but also their evasion of host immune defenses. Many pathogenic bacteria or opportunistic pathogens infect the host and lead to significant changes in metabolites, especially the proteinogenic amino acids, to inhibit the host's immune mechanism to achieve its immune evasion and pathogenicity. Here, we review the regulation of host metabolism, while host cells are infected by some common pathogenic bacteria, and discuss how amino acids of metabolic reprogramming affect bacterial infections, revealing the potential adjunctive application of amino acids alongside antibiotics.
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Affiliation(s)
- Xiao-Yue Li
- The First School of Clinical Medicine, Southern Medical University, Guangdong, 510515, China
| | - Zi-Xin Zeng
- The First School of Clinical Medicine, Southern Medical University, Guangdong, 510515, China
| | - Zhi-Xing Cheng
- The First School of Clinical Medicine, Southern Medical University, Guangdong, 510515, China
| | - Yi-Lin Wang
- The First School of Clinical Medicine, Southern Medical University, Guangdong, 510515, China
| | - Liang-Jun Yuan
- The First School of Clinical Medicine, Southern Medical University, Guangdong, 510515, China
| | - Zhi-Yong Zhai
- Shenzhen Hospital, Southern Medical University, Shenzhen Clinical Medical College, Southern Medical University, Guangdong, 518101, China.
| | - Wei Gong
- Shenzhen Hospital, Southern Medical University, Shenzhen Clinical Medical College, Southern Medical University, Guangdong, 518101, China.
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4
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Green AE, Pottenger S, Monshi MS, Barton TE, Phelan M, Neill DR. Airway metabolic profiling during Streptococcus pneumoniae infection identifies branched chain amino acids as signatures of upper airway colonisation. PLoS Pathog 2023; 19:e1011630. [PMID: 37669280 PMCID: PMC10503754 DOI: 10.1371/journal.ppat.1011630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 09/15/2023] [Accepted: 08/21/2023] [Indexed: 09/07/2023] Open
Abstract
Streptococcus pneumoniae is a leading cause of community-acquired pneumonia and bacteraemia and is capable of remarkable phenotypic plasticity, responding rapidly to environmental change. Pneumococcus is a nasopharyngeal commensal, but is responsible for severe, acute infections following dissemination within-host. Pneumococcus is adept at utilising host resources, but the airways are compartmentalised and those resources are not evenly distributed. Challenges and opportunities in metabolite acquisition within different airway niches may contribute to the commensal-pathogen switch when pneumococcus moves from nasopharynx into lungs. We used NMR to characterise the metabolic landscape of the mouse airways, in health and during infection. Using paired nasopharynx and lung samples from naïve animals, we identified fundamental differences in metabolite bioavailability between airway niches. Pneumococcal pneumonia was associated with rapid and dramatic shifts in the lung metabolic environment, whilst nasopharyngeal carriage led to only modest change in upper airway metabolite profiles. NMR spectra derived from the nasopharynx of mice infected with closely-related pneumococcal strains that differ in their colonisation potential could be distinguished from one another using multivariate dimensionality reduction methods. The resulting models highlighted that increased branched-chain amino acid (BCAA) bioavailability in nasopharynx is a feature of infection with the high colonisation potential strain. Subsequent analysis revealed increased expression of BCAA transport genes and increased intracellular concentrations of BCAA in that same strain. Movement from upper to lower airway environments is associated with shifting challenges in metabolic resource allocation for pneumococci. Efficient biosynthesis, liberation or acquisition of BCAA is a feature of adaptation to nasopharyngeal colonisation.
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Affiliation(s)
- Angharad E. Green
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Sian Pottenger
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Manal S. Monshi
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Thomas E. Barton
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Marie Phelan
- Highfield NMR Facility, Liverpool Shared Research Facilities (LIV-SRF), University of Liverpool, Liverpool, United Kingdom
- Department of Biochemistry and Systems Biology, Institute of Molecular, Systems and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Daniel R. Neill
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
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How To Deal with Toxic Amino Acids: the Bipartite AzlCD Complex Exports Histidine in Bacillus subtilis. J Bacteriol 2022; 204:e0035322. [PMID: 36377869 PMCID: PMC9765041 DOI: 10.1128/jb.00353-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The Gram-positive model bacterium Bacillus subtilis can use several amino acids as sources of carbon and nitrogen. However, some amino acids inhibit the growth of this bacterium. This amino acid toxicity is often enhanced in strains lacking the second messenger cyclic dimeric adenosine 3',5'-monophosphate (c-di-AMP). We observed that the presence of histidine is also toxic for a B. subtilis strain that lacks all three c-di-AMP synthesizing enzymes. However, suppressor mutants emerged, and whole-genome sequencing revealed mutations in the azlB gene that encode the repressor of the azl operon. This operon encodes an exporter and an importer for branched-chain amino acids. The suppressor mutations result in an overexpression of the azl operon. Deletion of the azlCD genes encoding the branched-chain amino acid exporter restored the toxicity of histidine, indicating that this exporter is required for histidine export and for resistance to otherwise toxic levels of the amino acid. The higher abundance of the amino acid exporter AzlCD increased the extracellular concentration of histidine, thus confirming the new function of AzlCD as a histidine exporter. Unexpectedly, the AzlB-mediated repression of the operon remains active even in the presence of amino acids, suggesting that the expression of the azl operon requires the mutational inactivation of AzlB. IMPORTANCE Amino acids are building blocks for protein biosynthesis in each living cell. However, due to their reactivity and the similarity between several amino acids, they may also be involved in harmful reactions or in noncognate interactions and thus may be toxic. Bacillus subtilis can deal with otherwise toxic histidine by overexpressing the bipartite amino acid exporter AzlCD. Although encoded in an operon that also contains a gene for an amino acid importer, the corresponding genes are not expressed, irrespective of the availability of amino acids in the medium. This suggests that the azl operon is a last resort by which to deal with histidine stress that can be expressed due to the mutational inactivation of the cognate repressor AzlB.
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Vahidinasab M, Adiek I, Hosseini B, Akintayo SO, Abrishamchi B, Pfannstiel J, Henkel M, Lilge L, Voegele RT, Hausmann R. Characterization of Bacillus velezensis UTB96, Demonstrating Improved Lipopeptide Production Compared to the Strain B. velezensis FZB42. Microorganisms 2022; 10:2225. [PMID: 36363818 PMCID: PMC9693074 DOI: 10.3390/microorganisms10112225] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 08/24/2023] Open
Abstract
Bacillus strains can produce various lipopeptides, known for their antifungal properties. This makes them attractive metabolites for applications in agriculture. Therefore, identification of productive wild-type strains is essential for the development of biopesticides. Bacillus velezensis FZB42 is a well-established strain for biocontrol of plant pathogens in agriculture. Here, we characterized an alternative strain, B. velezensis UTB96, that can produce higher amounts of all three major lipopeptide families, namely surfactin, fengycin, and iturin. UTB96 produces iturin A. Furthermore, UTB96 showed superior antifungal activity towards the soybean fungal pathogen Diaporthe longicolla compared to FZB42. Moreover, the additional provision of different amino acids for lipopeptide production in UTB96 was investigated. Lysine and alanine had stimulatory effects on the production of all three lipopeptide families, while supplementation of leucine, valine and isoleucine decreased the lipopeptide bioproduction. Using a 45-litre bioreactor system for upscaling in batch culture, lipopeptide titers of about 140 mg/L surfactin, 620 mg/L iturin A, and 45 mg/L fengycin were achieved. In conclusion, it becomes clear that B. velezensis UTB96 is a promising strain for further research application in the field of agricultural biological controls of fungal diseases.
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Affiliation(s)
- Maliheh Vahidinasab
- Department of Bioprocess Engineering (150k), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstraße 12, 70599 Stuttgart, Germany
| | - Isabel Adiek
- Department of Bioprocess Engineering (150k), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstraße 12, 70599 Stuttgart, Germany
| | - Behnoush Hosseini
- Department of Phytopathology (360a), Institute of Phytomedicine, Faculty of Agricultural Sciences, University of Hohenheim, Otto-Sander-Str. 5, 70599 Stuttgart, Germany
| | - Stephen Olusanmi Akintayo
- Department of Bioprocess Engineering (150k), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstraße 12, 70599 Stuttgart, Germany
| | - Bahar Abrishamchi
- Department of Bioprocess Engineering (150k), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstraße 12, 70599 Stuttgart, Germany
| | - Jens Pfannstiel
- Core Facility Hohenheim, Mass Spectrometry Unit, University of Hohenheim, August-von-Hartmann-Str. 3, 70599 Stuttgart, Germany
| | - Marius Henkel
- Cellular Agriculture, TUM School of Life Science, Technical University of Munich, Gregor-Mendel-Str. 4, 85354 Freising, Germany
| | - Lars Lilge
- Department of Bioprocess Engineering (150k), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstraße 12, 70599 Stuttgart, Germany
| | - Ralf T. Voegele
- Department of Phytopathology (360a), Institute of Phytomedicine, Faculty of Agricultural Sciences, University of Hohenheim, Otto-Sander-Str. 5, 70599 Stuttgart, Germany
| | - Rudolf Hausmann
- Department of Bioprocess Engineering (150k), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstraße 12, 70599 Stuttgart, Germany
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7
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Reconsidering the in vivo functions of Clostridial Stickland amino acid fermentations. Anaerobe 2022; 76:102600. [PMID: 35709938 PMCID: PMC9831356 DOI: 10.1016/j.anaerobe.2022.102600] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 06/03/2022] [Indexed: 01/13/2023]
Abstract
Stickland amino acid fermentations occur primarily among species of Clostridia. An ancient form of metabolism, Stickland fermentations use amino acids as electron acceptors in the absence of stronger oxidizing agents and provide metabolic capabilities to support growth when other fermentable substrates, such as carbohydrates, are lacking. The reactions were originally described as paired fermentations of amino acid electron donors, such as the branched-chain amino acids, with recipients that include proline and glycine. We present a redox-focused view of Stickland metabolism following electron flow through metabolically diverse oxidative reactions and the defined-substrate reductase systems, including for proline and glycine, and the role of dual redox pathways for substrates such as leucine and ornithine. Genetic studies and Environment and Gene Regulatory Interaction Network (EGRIN) models for the pathogen Clostridioides difficile have improved our understanding of the regulation and metabolic recruitment of these systems, and their functions in modulating inter-species interactions within host-pathogen-commensal systems and uses in industrial and environmental applications.
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8
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Wang M, Wamp S, Gibhardt J, Holland G, Schwedt I, Schmidtke KU, Scheibner K, Halbedel S, Commichau FM. Adaptation of Listeria monocytogenes to perturbation of c-di-AMP metabolism underpins its role in osmoadaptation and identifies a fosfomycin uptake system. Environ Microbiol 2022; 24:4466-4488. [PMID: 35688634 DOI: 10.1111/1462-2920.16084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/25/2022] [Indexed: 11/29/2022]
Abstract
The human pathogen Listeria monocytogenes synthesizes and degrades c-di-AMP using the diadenylate cyclase CdaA and the phosphodiesterases PdeA and PgpH respectively. c-di-AMP is essential because it prevents the uncontrolled uptake of osmolytes. Here, we studied the phenotypes of cdaA, pdeA, pgpH and pdeA pgpH mutants with defects in c-di-AMP metabolism and characterized suppressor mutants restoring their growth defects. The characterization of the pdeA pgpH mutant revealed that the bacteria show growth defects in defined medium, a phenotype that is invariably suppressed by mutations in cdaA. The previously reported growth defect of the cdaA mutant in rich medium is suppressed by mutations that osmotically stabilize the c-di-AMP-free strain. We also found that the cdaA mutant has an increased sensitivity against isoleucine. The isoleucine-dependent growth inhibition of the cdaA mutant is suppressed by codY mutations that likely reduce the DNA-binding activity of encoded CodY variants. Moreover, the characterization of the cdaA suppressor mutants revealed that the Opp oligopeptide transport system is involved in the uptake of the antibiotic fosfomycin. In conclusion, the suppressor analysis corroborates a key function of c-di-AMP in controlling osmolyte homeostasis in L. monocytogenes.
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Affiliation(s)
- Mengyi Wang
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, 01968, Senftenberg, Germany.,Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany.,FG Molecular Microbiology, Institute of Biology, University of Hohenheim, 70599, Stuttgart, Germany
| | - Sabrina Wamp
- Division of Enteropathogenic Bacteria and Legionella, Robert-Koch-Institute, 38855, Wernigerode, Germany
| | - Johannes Gibhardt
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, 01968, Senftenberg, Germany.,Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany.,Research Complex NanoBio, Peter the Great Saint Petersburg Polytechnic University, Politekhnicheskaya ulitsa 29A, Saint Petersburg, 195251, Russia
| | - Gudrun Holland
- ZBS4 - Advanced Light and Electron Microscopy, Robert-Koch-Institute, Seestraße 10, 13353, Berlin, Germany
| | - Inge Schwedt
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, 01968, Senftenberg, Germany.,FG Molecular Microbiology, Institute of Biology, University of Hohenheim, 70599, Stuttgart, Germany
| | - Kai-Uwe Schmidtke
- FG Enzyme Technology, Institute for Biotechnology, BTU Cottbus-Senftenberg, 01968, Senftenberg, Germany
| | - Katrin Scheibner
- FG Enzyme Technology, Institute for Biotechnology, BTU Cottbus-Senftenberg, 01968, Senftenberg, Germany
| | - Sven Halbedel
- Division of Enteropathogenic Bacteria and Legionella, Robert-Koch-Institute, 38855, Wernigerode, Germany
| | - Fabian M Commichau
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, 01968, Senftenberg, Germany.,FG Molecular Microbiology, Institute of Biology, University of Hohenheim, 70599, Stuttgart, Germany
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9
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Kharnaior P, Tamang JP. Metagenomic-Metabolomic Mining of Kinema, a Naturally Fermented Soybean Food of the Eastern Himalayas. Front Microbiol 2022; 13:868383. [PMID: 35572705 PMCID: PMC9106393 DOI: 10.3389/fmicb.2022.868383] [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: 02/02/2022] [Accepted: 02/24/2022] [Indexed: 12/18/2022] Open
Abstract
Kinema is a popular sticky fermented soybean food of the Eastern Himalayan regions of North East India, east Nepal, and south Bhutan. We hypothesized that some dominant bacteria in kinema may contribute to the formation of targeted and non-targeted metabolites for health benefits; hence, we studied the microbiome-metabolite mining of kinema. A total of 1,394,094,912 bp with an average of 464,698,304 ± 120,720,392 bp was generated from kinema metagenome, which resulted in the identification of 47 phyla, 331 families, 709 genera, and 1,560 species. Bacteria (97.78%) were the most abundant domain with the remaining domains of viruses, eukaryote, and archaea. Firmicutes (93.36%) was the most abundant phylum with 280 species of Bacillus, among which Bacillus subtilis was the most dominant species in kinema followed by B. glycinifermentans, B. cereus, B. licheniformis, B. thermoamylovorans, B. coagulans, B. circulans, B. paralicheniformis, and Brevibacillus borstelensis. Predictive metabolic pathways revealed the abundance of genes associated with metabolism (60.66%), resulting in 216 sub-pathways. A total of 361 metabolites were identified by metabolomic analysis (liquid chromatography-mass spectrophotometry, LC-MS). The presence of metabolites, such as chrysin, swainsonine, and 3-hydroxy-L-kynurenine (anticancer activity) and benzimidazole (antimicrobial, anticancer, and anti-HIV activities), and compounds with immunomodulatory effects in kinema supports its therapeutic potential. The correlation between the abundant species of Bacillus and primary and secondary metabolites was constructed with a bivariate result. This study proves that Bacillus spp. contribute to the formation of many targeted and untargeted metabolites in kinema for health-promoting benefits.
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Affiliation(s)
| | - Jyoti Prakash Tamang
- Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok, India
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10
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Abstract
Bacillus anthracis, the anthrax agent, exhibits robust proliferation in diverse niches of mammalian hosts. The metabolic attributes of B. anthracis that permit rapid growth in multiple mammalian tissues have not been established. We posit that branched-chain amino acid (BCAA) (isoleucine, leucine, and valine) metabolism is key to B. anthracis pathogenesis. Increasing evidence indicates the relationships between B. anthracis virulence and the expression of BCAA-related genes. The expression of some BCAA-related genes is altered during culture in bovine blood in vitro, and the bacterium exhibits valine auxotrophy in a blood serum mimic medium. Transcriptome analyses have revealed that the virulence regulator AtxA, which positively affects the expression of the anthrax toxin and capsule genes, negatively regulates genes predicted to be associated with BCAA biosynthesis and transport. Here, we show that B. anthracis growth in defined medium is severely restricted in the absence of exogenous BCAAs, indicating that BCAA transport is required for optimal growth in vitro. We demonstrate functional redundancy among multiple BrnQ-type BCAA transporters. Three transporters are associated with isoleucine and valine transport, and the deletion of one, BrnQ3, attenuates virulence in a murine model for anthrax. Interestingly, an ilvD-null mutant lacking dihydroxy acid dehydratase, an enzyme essential for BCAA synthesis, exhibits unperturbed growth when cultured in medium containing BCAAs but is highly attenuated in the murine model. Finally, our data show that BCAAs enhance AtxA activity in a dose-dependent manner, suggesting a model in which BCAAs serve as a signal for virulence gene expression. IMPORTANCE Infection with B. anthracis can result in systemic disease with large numbers of the bacterium in multiple tissues. We found that branched-chain amino acid (BCAA) synthesis is insufficient for the robust growth of B. anthracis; access to BCAAs is necessary for the proliferation of the pathogen during culture and during infection in a murine model for anthrax. B. anthracis produces an unusually large repertoire of BCAA-related transporters. We identified three isoleucine/valine transporters with partial functional redundancy during culture. The deletion of one of these transporters, BrnQ3, resulted in attenuated virulence. Interestingly, a BCAA biosynthesis mutant grew well in medium containing BCAAs but, like BrnQ3, was attenuated for virulence. These results suggest that BCAAs are limiting in multiple niches during infection and further our understanding of the nutritional requirements of this important pathogen.
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11
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Systems-level analysis of the global regulatory mechanism of CodY in Lactococcus lactis metabolism and nisin immunity modulation. Appl Environ Microbiol 2022; 88:e0184721. [PMID: 35044848 DOI: 10.1128/aem.01847-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacteria adapt to the constantly changing environment by regulating their metabolism. The global transcriptional regulator CodY is known to regulate metabolism in low G+C Gram-positive bacteria. Systems-level identification of its direct targets by proteome and ChIP-seq assays was rarely reported. Here, we identified CodY serves as an activator or a repressor of hundreds of genes involved in nitrogen metabolism, carbohydrate metabolism, and transcription through iTRAQ proteome and ChIP-seq. Combined with EMSA experiment, apart from the genes associated with amino acid biosynthesis (ilvD, leuA, optS, ybbD, dtpT, and pepN), genes involved in cell wall synthesis (murD and ftsW) and nisin immunity (nisI) were identified to be regulated by CodY. Moreover, it was demonstrated that CodY activated the transcription of nisI and contributed to the nisin immunity by nisin resistance assay. Intriguingly, CodY showed a self-regulation through binding to the motif 'AAAGGTGTGACAACT'in the CDS region of codY verified by DNase I footprinting assay and MEME analysis. In addition, a novel conserved AT-rich motif 'AATWTTCTGACAATT' was obtained in L. lactis F44. This study provides new insights into the comprehensive CodY regulation in L. lactis by controlling metabolism, nisin immunity and self-expression. Importance Lactococcus lactis, a widely used lactic acid bacteria (LAB) in the food fermentation, has been the model strain in genetic engineering, and its application has extended from food to microbial cell factory. CodY is a global regulator in low G+C Gram-positive bacteria. Its function and direct target genes in genome-level were rarely known in L. lactis. In this study, we described the comprehensive regulation mechanism of CodY. It widely modulated the metabolism of nitrogen and carbohydrate, cell wall synthesis and nisin immunity in L. lactis F44, and its expression level was regulated by feedback control.
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12
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Functional Characterization of Transporters for L-Aspartate in Bacillus licheniformis. FERMENTATION 2022. [DOI: 10.3390/fermentation8010022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Amino acid efflux and influx transport systems play vital roles in industrial microorganisms’ cell growth and metabolism. However, although biochemically characterized, most of them remain unknown at the molecular level in Bacillus licheniformis. In this study, three proteins, namely, YdgF, YvbW, and YveA, were predicted to be involved in the active transport of L-aspartate (L-Asp). This was verified by manipulating their encoding genes. When growing in the minimal medium with L-Asp as the only carbon and nitrogen source, the growth of strains lacking proteins YdgF, YvbW, and YveA was significantly inhibited compared with the wild-type strains, while supplementing the expression of the corresponding proteins in the single-gene knockout strains could alleviate the inhibition. Upon overexpression, the recombinant proteins mediated the accumulation of L-aspartate to varying degrees. Compared with the wild-type strains, the single knockout strains of the three protein genes exhibited reduced absorption of L-aspartate. In addition, this study focused on the effects of these three proteins on the absorption of β-alanine, L-glutamate, D-serine, D-alanine, and glycine.
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13
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Tamang JP, Das S, Kharnaior P, Pariyar P, Thapa N, Jo SW, Yim EJ, Shin DH. Shotgun metagenomics of Cheonggukjang, a fermented soybean food of Korea: Community structure, predictive functionalities and amino acids profile. Food Res Int 2022; 151:110904. [PMID: 34980421 DOI: 10.1016/j.foodres.2021.110904] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 09/10/2021] [Accepted: 12/13/2021] [Indexed: 12/11/2022]
Abstract
Cheonggukjang is a naturally fermented soybean food of Korea. The present study was aimed to reveal the whole microbial community structure of naturally fermented cheonggukjang along with the prediction of microbial functional profiles by shotgun metagenomic sequence analysis. Metataxonomic profile of cheonggukjang samples showed different domains viz. bacteria (95.83%), virus (2.26%), unclassified (1.84%), eukaryotes (0.05%) and archaea (0.005%). Overall, 44 phyla, 286 families, 722 genera and 1437 species were identified. Firmicutes was the most abundant phylum (98.04%) followed by Proteobacteria (1.49%), Deinococcus-Thermus (0.14%). Bacillus thermoamylovorans was the most abundant species in cheonggukjang followed by Bacillus licheniformis, Bacillus glycinifermentans, Bacillus subtilis, Bacillus paralicheniformis, Bacillus amyloliquifaciens, Brevibacillus borstelensis, Brevibacillus sonorensis Brevibacillus, Acinetobacter, Carnobacterium, Paenibacillus, Cronobacter Enterococcus, Enterobacter, Terriglobus, Psychrobacter and Virgibacillus. A colossal diversity of the genus Bacillus was detected with 150 species. Functional analysis of cheonggukjang metagenome revealed the genes for the synthesis and metabolism of wide range of bioactive compounds including, various essential amino acids, conjugated amino acids, different vitamins, flavonoids, and enzymes. Amino acid profiles obtained from KEGG annotation in cheonggukjang were validated with experimental result of amino acid profiles.
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Affiliation(s)
- Jyoti Prakash Tamang
- DAICENTER (DBT-AIST International Centre for Translational and Environmental Research) and Bioinformatics Centre, Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok 737102, Sikkim, India.
| | - Souvik Das
- DAICENTER (DBT-AIST International Centre for Translational and Environmental Research) and Bioinformatics Centre, Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok 737102, Sikkim, India
| | - Pynhunlang Kharnaior
- DAICENTER (DBT-AIST International Centre for Translational and Environmental Research) and Bioinformatics Centre, Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok 737102, Sikkim, India
| | - Priyambada Pariyar
- DAICENTER (DBT-AIST International Centre for Translational and Environmental Research) and Bioinformatics Centre, Department of Microbiology, School of Life Sciences, Sikkim University, Gangtok 737102, Sikkim, India
| | - Namrata Thapa
- Biotech Hub, Department of Zoology, Nar Bahadur Bhandari Degree College, Sikkim University, Tadong 737102, Sikkim, India.
| | - Seung-Wha Jo
- Microbial Institute for Fermentation Industry (MIFI), Sunchang 56048, Republic of Korea
| | - Eun-Jung Yim
- Microbial Institute for Fermentation Industry (MIFI), Sunchang 56048, Republic of Korea
| | - Dong-Hwa Shin
- Shindonghwa Food Research Institute, Seoul 06192, Republic of Korea
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Baggio G, Groves RA, Chignola R, Piacenza E, Presentato A, Lewis IA, Lampis S, Vallini G, Turner RJ. Untargeted Metabolomics Investigation on Selenite Reduction to Elemental Selenium by Bacillus mycoides SeITE01. Front Microbiol 2021; 12:711000. [PMID: 34603239 PMCID: PMC8481872 DOI: 10.3389/fmicb.2021.711000] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 08/16/2021] [Indexed: 12/02/2022] Open
Abstract
Bacillus mycoides SeITE01 is an environmental isolate that transforms the oxyanion selenite (SeO 3 2 - ) into the less bioavailable elemental selenium (Se0) forming biogenic selenium nanoparticles (Bio-SeNPs). In the present study, the reduction of sodium selenite (Na2SeO3) by SeITE01 strain and the effect ofSeO 3 2 - exposure on the bacterial cells was examined through untargeted metabolomics. A time-course approach was used to monitor both cell pellet and cell free spent medium (referred as intracellular and extracellular, respectively) metabolites in SeITE01 cells treated or not withSeO 3 2 - . The results show substantial biochemical changes in SeITE01 cells when exposed toSeO 3 2 - . The initial uptake ofSeO 3 2 - by SeITE01 cells (3h after inoculation) shows both an increase in intracellular levels of 4-hydroxybenzoate and indole-3-acetic acid, and an extracellular accumulation of guanosine, which are metabolites involved in general stress response adapting strategies. Proactive and defensive mechanisms againstSeO 3 2 - are observed between the end of lag (12h) and beginning of exponential (18h) phases. Glutathione and N-acetyl-L-cysteine are thiol compounds that would be mainly involved in Painter-type reaction for the reduction and detoxification ofSeO 3 2 - to Se0. In these growth stages, thiol metabolites perform a dual role, both acting against the toxic and harmful presence of the oxyanion and as substrate or reducing sources to scavenge ROS production. Moreover, detection of the amino acids L-threonine and ornithine suggests changes in membrane lipids. Starting from stationary phase (24 and 48h), metabolites related to the formation and release of SeNPs in the extracellular environment begin to be observed. 5-hydroxyindole acetate, D-[+]-glucosamine, 4-methyl-2-oxo pentanoic acid, and ethanolamine phosphate may represent signaling strategies following SeNPs release from the cytoplasmic compartment, with consequent damage to SeITE01 cell membranes. This is also accompanied by intracellular accumulation of trans-4-hydroxyproline and L-proline, which likely represent osmoprotectant activity. The identification of these metabolites suggests the activation of signaling strategies that would protect the bacterial cells fromSeO 3 2 - toxicity while it is converting into SeNPs.
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Affiliation(s)
- Greta Baggio
- Department of Biotechnology, University of Verona, Verona, Italy
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Ryan A. Groves
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Roberto Chignola
- Department of Biotechnology, University of Verona, Verona, Italy
| | - Elena Piacenza
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Alessandro Presentato
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Ian A. Lewis
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Silvia Lampis
- Department of Biotechnology, University of Verona, Verona, Italy
| | - Giovanni Vallini
- Department of Biotechnology, University of Verona, Verona, Italy
| | - Raymond J. Turner
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
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Bharanidharan R, Lee CH, Thirugnanasambantham K, Ibidhi R, Woo YW, Lee HG, Kim JG, Kim KH. Feeding Systems and Host Breeds Influence Ruminal Fermentation, Methane Production, Microbial Diversity and Metagenomic Gene Abundance. Front Microbiol 2021; 12:701081. [PMID: 34354694 PMCID: PMC8329423 DOI: 10.3389/fmicb.2021.701081] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/28/2021] [Indexed: 12/12/2022] Open
Abstract
Our previous research revealed the advantages of separate feeding (SF) systems compared to total mixed ration (TMR) in terms of ruminal methane (CH4) production. The purpose of this experiment was to confirm the advantage of SF as a nutritional strategy for CH4 mitigation, and to determine the effects of different feeding systems (TMR and SF) on the rumen microbiome and associated metagenome of two different breeds and on CH4 emissions. We randomly allocated four Holstein (305 ± 29 kg) and four Hanwoo steers (292 ± 24 kg) to two groups; the steers were fed a commercial concentrate with tall fescue (75:25) as TMR or SF, in a crossover design (two successive 22-day periods). Neither feeding systems nor cattle breeds had an effect on the total tract digestibility of nutrients. The TMR feeding system and Hanwoo steers generated significantly more CH4 (P < 0.05) and had a higher yield [g/d and g/kg dry matter intake (DMI)] compared to the SF system and Holstein steers. A larger rumen acetate:propionate ratio was observed for the TMR than the SF diet (P < 0.05), and for Hanwoo than Holstein steers (P < 0.001), clearly reflecting a shift in the ruminal H2 sink toward CH4 production. The linear discriminant analysis (LDA) effect size (LEfSe) revealed a greater abundance (α < 0.05 and LDA > 2.0) of operational taxonomic units (OTUs) related to methanogenesis for Hanwoo steers compared to Holstein steers. Kendall’s correlation analysis revealed wide variation of microbial co-occurrence patterns between feeding systems, indicating differential H2 thermodynamics in the rumen. A metagenome analysis of rumen microbes revealed the presence of 430 differentially expressed genes, among which 17 and 27 genes exhibited positive and negative associations with CH4 production, respectively (P < 0.001). A strong interaction between feeding system and breed was observed for microbial and metagenomic abundance. Overall, these results suggest that the TMR feeding system produces more CH4, and that Hanwoo cattle are higher CH4 emitters than SF diet and Holstein cattle, respectively. Interestingly, host-associated microbial interactions differed within each breed depending on the feeding system, which indicated that breed-specific feeding systems should be taken into account for farm management.
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Affiliation(s)
- Rajaraman Bharanidharan
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Chang Hyun Lee
- Cargill Agri Purina Inc., Technology Application Center, Pyeongchang, South Korea
| | - Krishnaraj Thirugnanasambantham
- Department of Ecofriendly Livestock Science, Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, South Korea.,Pondicherry Centre for Biological Science and Educational Trust, Tamil Nadu, India
| | - Ridha Ibidhi
- Department of Ecofriendly Livestock Science, Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, South Korea
| | | | - Hong-Gu Lee
- Department of Animal Science and Technology, SangHa Life Science College, Konkuk University, Seoul, South Korea
| | - Jong Geun Kim
- Department of Ecofriendly Livestock Science, Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, South Korea.,Department of International Agricultural Technology, Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang, South Korea
| | - Kyoung Hoon Kim
- Department of Ecofriendly Livestock Science, Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, South Korea.,Department of International Agricultural Technology, Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang, South Korea
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16
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Sun J, Liu Y, Lin F, Lu Z, Lu Y. CodY, ComA, DegU and Spo0A controlling lipopeptides biosynthesis in Bacillus amyloliquefaciens fmbJ. J Appl Microbiol 2021; 131:1289-1304. [PMID: 33460520 DOI: 10.1111/jam.15007] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 01/09/2023]
Abstract
AIM In the study, we investigated the regulatory effects of these genes (codY, comA, degU and spo0A) on the biosynthesis of three lipopeptides (bacillomycin D, fengycin and surfactin) in Bacillus amyloliquefaciens. METHODS AND RESULTS The codY, comA, degU and spo0A genes in B. amyloliquefaciens fmbJ were knocked out. The results showed that the productions of bacillomycin D were significantly reduced compared with that of fmbJ. Their deletion induced great changes in the levels of transcripts specifying metabolic pathways, quorum sensing system and substance transport system in fmbJ. Moreover, overexpression of these genes improved the productions of bacillomycin D. In particular, the overexpression of spo0A enhanced bacillomycin D yield up to 648·9 ± 60·9 mg l-1 from 277·3 ± 30·5 mg l-1 . In addition, the yields of surfactin in fmbJΔcodY and fmbJΔdegU were significantly improved, and the regulatory factor CodY had no significant effect on the synthesis of fengycin. CONCLUSIONS These genes positively regulated the expression of bacillomycin D and fengycin synthase genes in strain fmbJ. However, codY and degU negatively regulated surfactin biosynthesis. Moreover, it was found that CodY had a concentration dependence on bacillomycin D synthesis. Spo0A might play a direct regulatory role in the synthesis and secretion of bacillomycin D. SIGNIFICANCE AND IMPACT OF THE STUDY This study indicated that genetic engineering of regulatory genes was an effective strategy to improve the yields of antimicrobial lipopeptides and provided promising strains for industrial production of lipopeptides.
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Affiliation(s)
- J Sun
- College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, People's Republic of China.,College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Y Liu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - F Lin
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Z Lu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Y Lu
- College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, People's Republic of China
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17
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The Food Poisoning Toxins of Bacillus cereus. Toxins (Basel) 2021; 13:toxins13020098. [PMID: 33525722 PMCID: PMC7911051 DOI: 10.3390/toxins13020098] [Citation(s) in RCA: 99] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/14/2021] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
Abstract
Bacillus cereus is a ubiquitous soil bacterium responsible for two types of food-associated gastrointestinal diseases. While the emetic type, a food intoxication, manifests in nausea and vomiting, food infections with enteropathogenic strains cause diarrhea and abdominal pain. Causative toxins are the cyclic dodecadepsipeptide cereulide, and the proteinaceous enterotoxins hemolysin BL (Hbl), nonhemolytic enterotoxin (Nhe) and cytotoxin K (CytK), respectively. This review covers the current knowledge on distribution and genetic organization of the toxin genes, as well as mechanisms of enterotoxin gene regulation and toxin secretion. In this context, the exceptionally high variability of toxin production between single strains is highlighted. In addition, the mode of action of the pore-forming enterotoxins and their effect on target cells is described in detail. The main focus of this review are the two tripartite enterotoxin complexes Hbl and Nhe, but the latest findings on cereulide and CytK are also presented, as well as methods for toxin detection, and the contribution of further putative virulence factors to the diarrheal disease.
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18
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Klewing A, Koo BM, Krüger L, Poehlein A, Reuß D, Daniel R, Gross CA, Stülke J. Resistance to serine in Bacillus subtilis: identification of the serine transporter YbeC and of a metabolic network that links serine and threonine metabolism. Environ Microbiol 2020; 22:3937-3949. [PMID: 32743959 PMCID: PMC8226366 DOI: 10.1111/1462-2920.15179] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 07/27/2020] [Indexed: 01/10/2023]
Abstract
The Gram‐positive bacterium Bacillus subtilis uses serine not only as a building block for proteins but also as an important precursor in many anabolic reactions. Moreover, a lack of serine results in the initiation of biofilm formation. However, excess serine inhibits the growth of B. subtilis. To unravel the underlying mechanisms, we isolated suppressor mutants that can tolerate toxic serine concentrations by three targeted and non‐targeted genome‐wide screens. All screens as well as genetic complementation in Escherichia coli identified the so far uncharacterized permease YbeC as the major serine transporter of B. subtilis. In addition to YbeC, the threonine transporters BcaP and YbxG make minor contributions to serine uptake. A strain lacking these three transporters was able to tolerate 100 mM serine whereas the wild type strain was already inhibited by 1 mM of the amino acid. The screen for serine‐resistant mutants also identified mutations that result in increased serine degradation and in increased expression of threonine biosynthetic enzymes suggesting that serine toxicity results from interference with threonine biosynthesis.
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Affiliation(s)
- Anika Klewing
- Department of General Microbiology, GZMB, Georg-August-University Göttingen, Grisebachstr. 8, Göttingen, D-37077, Germany
| | - Byoung-Mo Koo
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Larissa Krüger
- Department of General Microbiology, GZMB, Georg-August-University Göttingen, Grisebachstr. 8, Göttingen, D-37077, Germany
| | - Anja Poehlein
- Department of Genomic and Applied Microbiology, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Daniel Reuß
- Department of General Microbiology, GZMB, Georg-August-University Göttingen, Grisebachstr. 8, Göttingen, D-37077, Germany
| | - Rolf Daniel
- Department of Genomic and Applied Microbiology, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Carol A Gross
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Jörg Stülke
- Department of General Microbiology, GZMB, Georg-August-University Göttingen, Grisebachstr. 8, Göttingen, D-37077, Germany
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19
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Wu F, Cai D, Li L, Li Y, Yang H, Li J, Ma X, Chen S. Modular metabolic engineering of lysine supply for enhanced production of bacitracin in Bacillus licheniformis. Appl Microbiol Biotechnol 2019; 103:8799-8812. [DOI: 10.1007/s00253-019-10110-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/12/2019] [Accepted: 08/28/2019] [Indexed: 02/06/2023]
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20
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Kumar J, Sharma N, Kaushal G, Samurailatpam S, Sahoo D, Rai AK, Singh SP. Metagenomic Insights Into the Taxonomic and Functional Features of Kinema, a Traditional Fermented Soybean Product of Sikkim Himalaya. Front Microbiol 2019; 10:1744. [PMID: 31428064 PMCID: PMC6688588 DOI: 10.3389/fmicb.2019.01744] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/15/2019] [Indexed: 12/19/2022] Open
Abstract
Kinema is an ethnic, naturally fermented soybean product consumed in the Sikkim Himalayan region of India. In the present study, the whole metagenome sequencing approach was adopted to examine the microbial diversity and related functional potential of Kinema, consumed in different seasons. Firmicutes was the abundant phylum in Kinema, ranging from 82.31 to 93.99% in different seasons, followed by Actinobacteria and Proteobacteria. At the species level, the prevalent microorganisms were Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis, Corynebacterium glutamicum, Bacillus pumilus, and Lactococcus lactis. The abundance of microbial species varied significantly in different seasons. Further, the genomic presence of some undesirable microbes like Bacillus cereus, Proteus mirabilis, Staphylococcus aureus, Proteus penneri, Enterococcus faecalis, and Staphylococcus saprophyticus, were also detected in the specific season. The metagenomic analysis also revealed the existence of bacteriophages belonging to the family Siphoviridae, Myoviridae, and Podoviridae. Examination of the metabolic potential of the Kinema metagenome depicted information about the biocatalysts, presumably involved in the transformation of protein and carbohydrate polymers into bioactive molecules of health-beneficial effects. The genomic resource of several desirable enzymes was identified, such as β-galactosidase, β-glucosidase, β-xylosidase, and glutamate decarboxylase, etc. The catalytic function of a novel glutamate decarboxylase gene was validated for the biosynthesis of γ-aminobutyric acid (GABA). The results of the present study highlight the microbial and genomic resources associated with Kinema, and its importance in functional food industry.
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Affiliation(s)
- Jitesh Kumar
- Center of Innovative and Applied Bioprocessing, Mohali, India
| | - Nitish Sharma
- Center of Innovative and Applied Bioprocessing, Mohali, India
| | - Girija Kaushal
- Center of Innovative and Applied Bioprocessing, Mohali, India
| | | | - Dinabandhu Sahoo
- Institute of Bioresources and Sustainable Development, Sikkim Centre, Tadong, India.,Institute of Bioresources and Sustainable Development, Imphal, India
| | - Amit K Rai
- Institute of Bioresources and Sustainable Development, Sikkim Centre, Tadong, India
| | - Sudhir P Singh
- Center of Innovative and Applied Bioprocessing, Mohali, India
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21
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Wicke D, Schulz LM, Lentes S, Scholz P, Poehlein A, Gibhardt J, Daniel R, Ischebeck T, Commichau FM. Identification of the first glyphosate transporter by genomic adaptation. Environ Microbiol 2019; 21:1287-1305. [PMID: 30666812 DOI: 10.1111/1462-2920.14534] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/17/2019] [Accepted: 01/18/2019] [Indexed: 01/12/2023]
Abstract
The soil bacterium Bacillus subtilis can get into contact with growth-inhibiting substances, which may be of anthropogenic origin. Glyphosate is such a substance serving as a nonselective herbicide. Glyphosate specifically inhibits the 5-enolpyruvyl-shikimate-3-phosphate (EPSP) synthase, which generates an essential precursor for de novo synthesis of aromatic amino acids in plants, fungi, bacteria and archaea. Inhibition of the EPSP synthase by glyphosate results in depletion of the cellular levels of aromatic amino acids unless the environment provides them. Here, we have assessed the potential of B. subtilis to adapt to glyphosate at the genome level. In contrast to Escherichia coli, which evolves glyphosate resistance by elevating the production and decreasing the glyphosate sensitivity of the EPSP synthase, B. subtilis primarily inactivates the gltT gene encoding the high-affinity glutamate/aspartate symporter GltT. Further adaptation of the gltT mutants to glyphosate led to the inactivation of the gltP gene encoding the glutamate transporter GltP. Metabolome analyses confirmed that GltT is the major entryway of glyphosate into B. subtilis. GltP, the GltT homologue of E. coli also transports glyphosate into B. subtilis. Finally, we found that GltT is involved in uptake of the herbicide glufosinate, which inhibits the glutamine synthetase.
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Affiliation(s)
- Dennis Wicke
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
| | - Lisa M Schulz
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
| | - Sabine Lentes
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
| | - Patricia Scholz
- Department for Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center of Molecular Biosciences (GZMB), University of Goettingen, 37077, Göttingen, Germany
| | - Anja Poehlein
- Department of Genomic and Applied Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
| | - Johannes Gibhardt
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
| | - Rolf Daniel
- Department of Genomic and Applied Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
| | - Till Ischebeck
- Department for Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center of Molecular Biosciences (GZMB), University of Goettingen, 37077, Göttingen, Germany
| | - Fabian M Commichau
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
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22
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Ostrov I, Sela N, Belausov E, Steinberg D, Shemesh M. Adaptation of Bacillus species to dairy associated environment facilitates their biofilm forming ability. Food Microbiol 2019; 82:316-324. [PMID: 31027789 DOI: 10.1016/j.fm.2019.02.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 02/17/2019] [Accepted: 02/28/2019] [Indexed: 12/22/2022]
Abstract
Biofilm-forming Bacillus species are often involved in contamination of dairy products and therefore present a major microbiological challenge in the field of food quality and safety. In this study, we sequenced and analyzed the genomes of milk- and non-milk-derived Bacillus strains, and evaluated their biofilm-formation potential in milk. Unlike non-dairy Bacillus isolates, the dairy-associated Bacillus strains were characterized by formation of robust submerged and air-liquid interface biofilm (pellicle) during growth in milk. Moreover, genome comparison analysis revealed notable differences in putative biofilm-associated determinants between the dairy and non-dairy Bacillus isolates, which correlated with biofilm phenotype. These results suggest that biofilm formation by Bacillus species might represent a presumable adaptation strategy to the dairy environment.
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Affiliation(s)
- Ievgeniia Ostrov
- Department of Food Sciences, Institute for Postharvest Technology and Food Sciences, Agricultural Research Organization (ARO) the Volcani Center, Rishon LeZion, Israel; Biofilm Research Laboratory, Hebrew University - Hadassah, Jerusalem, Israel.
| | - Noa Sela
- Department of Plant Pathology and Weed Research, ARO, The Volcani Center, Rishon LeZion, Israel.
| | - Eduard Belausov
- Department of Ornamental Plants and Agricultural Biotechnology, ARO, The Volcani Center, Rishon LeZion, Israel.
| | - Doron Steinberg
- Biofilm Research Laboratory, Hebrew University - Hadassah, Jerusalem, Israel.
| | - Moshe Shemesh
- Department of Food Sciences, Institute for Postharvest Technology and Food Sciences, Agricultural Research Organization (ARO) the Volcani Center, Rishon LeZion, Israel.
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23
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Bai W, Geng W, Wang S, Zhang F. Biosynthesis, regulation, and engineering of microbially produced branched biofuels. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:84. [PMID: 31011367 PMCID: PMC6461809 DOI: 10.1186/s13068-019-1424-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 04/03/2019] [Indexed: 05/13/2023]
Abstract
The steadily increasing demand on transportation fuels calls for renewable fuel replacements. This has attracted a growing amount of research to develop advanced biofuels that have similar physical, chemical, and combustion properties with petroleum-derived fossil fuels. Early generations of biofuels, such as ethanol, butanol, and straight-chain fatty acid-derived esters or hydrocarbons suffer from various undesirable properties and can only be blended in limited amounts. Recent research has shifted to the production of branched-chain biofuels that, compared to straight-chain fuels, have higher octane values, better cold flow, and lower cloud points, making them more suitable for existing engines, particularly for diesel and jet engines. This review focuses on several types of branched-chain biofuels and their immediate precursors, including branched short-chain (C4-C8) and long-chain (C15-C19)-alcohols, alkanes, and esters. We discuss their biosynthesis, regulation, and recent efforts in their overproduction by engineered microbes.
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Affiliation(s)
- Wenqin Bai
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, Saint Louis, MO 63130 USA
| | - Weitao Geng
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, Saint Louis, MO 63130 USA
| | - Shaojie Wang
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, Saint Louis, MO 63130 USA
| | - Fuzhong Zhang
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, Saint Louis, MO 63130 USA
- Division of Biological & Biomedical Sciences, Washington University in St. Louis, Saint Louis, MO 63130 USA
- Institute of Materials Science & Engineering, Washington University in St. Louis, Saint Louis, MO 63130 USA
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24
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Enhancement of precursor amino acid supplies for improving bacitracin production by activation of branched chain amino acid transporter BrnQ and deletion of its regulator gene lrp in Bacillus licheniformis. Synth Syst Biotechnol 2018; 3:236-243. [PMID: 30417137 PMCID: PMC6215969 DOI: 10.1016/j.synbio.2018.10.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/07/2018] [Accepted: 10/24/2018] [Indexed: 11/21/2022] Open
Abstract
Bacitracin, a new type of cyclic peptide antibiotic, is widely used as the feed additive in feed industry. Branched chain amino acids (BCAAs) are the key precursors for bacitracin synthesis. In this research, soybean meal was served as the raw material to supply precursor amino acids for bacitracin synthesis, and enhanced production of bacitracin was attempted by engineering BCAA transporter BrnQ and its regulator Lrp in the bacitracin industrial production strain Bacillus licheniformis DW2. Firstly, our results confirmed that Lrp negatively affected bacitracin synthesis in DW2, and deletion of lrp improved intracellular BCAA accumulations, as well as the expression level of BCAA transporter BrnQ, which further led to a 14.71% increase of bacitracin yield, compared with that of DW2. On the contrary, overexpression of Lrp decreased bacitracin yield by 12.28%. Secondly, it was suggested that BrnQ acted as a BCAA importer in DW2, and overexpression of BrnQ enhanced the intracellular BCAA accumulations and 10.43% of bacitracin yield. While, the bacitracin yield decreased by 18.27% in the brnQ deletion strain DW2△brnQ. Finally, BrnQ was further overexpressed in lrp deletion strain DW2△lrp, and bacitracin yield produced by the final strain DW2△lrp::BrnQ was 965.34 U/mL, increased by 22.42% compared with that of DW2 (788.48 U/mL). Collectively, this research confirmed that Lrp affected bacitracin synthesis via regulating the expression of BCAA transporter BrnQ and BCAA distributions, and provided a promising strain for industrial production of bacitracin.
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25
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Westbrook AW, Ren X, Moo‐Young M, Chou CP. Metabolic engineering ofBacillus subtilisforl‐valine overproduction. Biotechnol Bioeng 2018; 115:2778-2792. [DOI: 10.1002/bit.26789] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 07/04/2018] [Accepted: 07/06/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Adam W. Westbrook
- Department of Chemical EngineeringUniversity of WaterlooWaterloo Ontario Canada
| | - Xiang Ren
- Department of Chemical EngineeringUniversity of WaterlooWaterloo Ontario Canada
| | - Murray Moo‐Young
- Department of Chemical EngineeringUniversity of WaterlooWaterloo Ontario Canada
| | - C. Perry Chou
- Department of Chemical EngineeringUniversity of WaterlooWaterloo Ontario Canada
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26
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Branching Out: Alterations in Bacterial Physiology and Virulence Due to Branched-Chain Amino Acid Deprivation. mBio 2018; 9:mBio.01188-18. [PMID: 30181248 PMCID: PMC6123439 DOI: 10.1128/mbio.01188-18] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The branched-chain amino acids (BCAAs [Ile, Leu, and Val]) represent important nutrients in bacterial physiology, with roles that range from supporting protein synthesis to signaling and fine-tuning the adaptation to amino acid starvation. In some pathogenic bacteria, the adaptation to amino acid starvation includes induction of virulence gene expression: thus, BCAAs support not only proliferation during infection, but also the evasion of host defenses. The branched-chain amino acids (BCAAs [Ile, Leu, and Val]) represent important nutrients in bacterial physiology, with roles that range from supporting protein synthesis to signaling and fine-tuning the adaptation to amino acid starvation. In some pathogenic bacteria, the adaptation to amino acid starvation includes induction of virulence gene expression: thus, BCAAs support not only proliferation during infection, but also the evasion of host defenses. A body of research has accumulated over the years to describe the multifaceted physiological roles of BCAAs and the mechanisms bacteria use to maintain their intracellular levels. More recent studies have focused on understanding how fluctuations in their intracellular levels impact global regulatory pathways that coordinate the adaptation to nutrient limitation, especially in pathogenic bacteria. In this minireview, we discuss how these studies have refined the individual roles of BCAAs, shed light on how BCAA auxotrophy might promote higher sensitivity to exogenous BCAA levels, and revealed pathogen-specific responses to BCAA deprivation. These advancements improve our understanding of how bacteria meet their nutritional requirements for growth while simultaneously remaining responsive to changes in environmental nutrient availability to promote their survival in a range of environments.
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27
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Complete Genome Sequences of Two Bacillus pumilus Strains from Cuatrociénegas, Coahuila, Mexico. GENOME ANNOUNCEMENTS 2018; 6:6/17/e00364-18. [PMID: 29700165 PMCID: PMC5920177 DOI: 10.1128/genomea.00364-18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We assembled the complete genome sequences of Bacillus pumilus strains 145 and 150a from Cuatrociénegas, Mexico. We detected genes codifying for proteins potentially involved in antagonism (bacteriocins) and defense mechanisms (abortive infection bacteriophage proteins and 4-azaleucine resistance). Both strains harbored prophage sequences. Our results provide insights into understanding the establishment of microbial interactions.
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Raynor MJ, Roh JH, Widen SG, Wood TG, Koehler TM. Regulons and protein-protein interactions of PRD-containing Bacillus anthracis virulence regulators reveal overlapping but distinct functions. Mol Microbiol 2018; 109:10.1111/mmi.13961. [PMID: 29603836 PMCID: PMC6167206 DOI: 10.1111/mmi.13961] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2018] [Indexed: 01/19/2023]
Abstract
Bacillus anthracis produces three regulators, AtxA, AcpA and AcpB, which control virulence gene transcription and belong to an emerging class of regulators termed 'PCVRs' (Phosphoenolpyruvate-dependent phosphotransferase regulation Domain-Containing Virulence Regulators). AtxA, named for its control of toxin gene expression, is the master virulence regulator and archetype PCVR. AcpA and AcpB are less well studied. Reports of PCVR activity suggest overlapping function. AcpA and AcpB independently positively control transcription of the capsule biosynthetic operon capBCADE, and culture conditions that enhance AtxA level or activity result in capBCADE transcription in strains lacking acpA and acpB. We used RNA-Seq to assess the regulons of the paralogous regulators in strains constructed to express individual PCVRs at native levels. Plasmid and chromosome-borne genes were PCVR controlled, with AtxA, AcpA and AcpB having a ≥ 4-fold effect on transcript levels of 145, 130 and 49 genes respectively. Several genes were coregulated by two or three PCVRs. We determined that AcpA and AcpB form homomultimers, as shown previously for AtxA, and we detected AtxA-AcpA heteromultimers. In co-expression experiments, AcpA activity was reduced by increased levels of AtxA. Our data show that the PCVRs have specific and overlapping activity and that PCVR stoichiometry and potential heteromultimerization can influence target gene expression.
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Affiliation(s)
- Malik J. Raynor
- Department of Microbiology and Molecular Genetics, McGovern Medical School of the University of Texas - Houston Health Science Center, Houston, Texas
- University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, Texas
| | - Jung-Hyeob Roh
- Department of Microbiology and Molecular Genetics, McGovern Medical School of the University of Texas - Houston Health Science Center, Houston, Texas
| | - Stephen G. Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Thomas G. Wood
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Theresa M. Koehler
- Department of Microbiology and Molecular Genetics, McGovern Medical School of the University of Texas - Houston Health Science Center, Houston, Texas
- University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, Texas
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29
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Kaiser JC, King AN, Grigg JC, Sheldon JR, Edgell DR, Murphy MEP, Brinsmade SR, Heinrichs DE. Repression of branched-chain amino acid synthesis in Staphylococcus aureus is mediated by isoleucine via CodY, and by a leucine-rich attenuator peptide. PLoS Genet 2018; 14:e1007159. [PMID: 29357354 PMCID: PMC5794164 DOI: 10.1371/journal.pgen.1007159] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 02/01/2018] [Accepted: 12/18/2017] [Indexed: 01/06/2023] Open
Abstract
Staphylococcus aureus requires branched-chain amino acids (BCAAs; isoleucine, leucine, valine) for protein synthesis, branched-chain fatty acid synthesis, and environmental adaptation by responding to their availability via the global transcriptional regulator CodY. The importance of BCAAs for S. aureus physiology necessitates that it either synthesize them or scavenge them from the environment. Indeed S. aureus uses specialized transporters to scavenge BCAAs, however, its ability to synthesize them has remained conflicted by reports that it is auxotrophic for leucine and valine despite carrying an intact BCAA biosynthetic operon. In revisiting these findings, we have observed that S. aureus can engage in leucine and valine synthesis, but the level of BCAA synthesis is dependent on the BCAA it is deprived of, leading us to hypothesize that each BCAA differentially regulates the biosynthetic operon. Here we show that two mechanisms of transcriptional repression regulate the level of endogenous BCAA biosynthesis in response to specific BCAA availability. We identify a trans-acting mechanism involving isoleucine-dependent repression by the global transcriptional regulator CodY and a cis-acting leucine-responsive attenuator, uncovering how S. aureus regulates endogenous biosynthesis in response to exogenous BCAA availability. Moreover, given that isoleucine can dominate CodY-dependent regulation of BCAA biosynthesis, and that CodY is a global regulator of metabolism and virulence in S. aureus, we extend the importance of isoleucine availability for CodY-dependent regulation of other metabolic and virulence genes. These data resolve the previous conflicting observations regarding BCAA biosynthesis, and reveal the environmental signals that not only induce BCAA biosynthesis, but that could also have broader consequences on S. aureus environmental adaptation and virulence via CodY.
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Affiliation(s)
- Julienne C. Kaiser
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Alyssa N. King
- Department of Biology, Georgetown University, Washington, DC, United States of America
| | - Jason C. Grigg
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jessica R. Sheldon
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - David R. Edgell
- Department of Biochemistry, University of Western Ontario, London, Ontario, Canada
| | - Michael E. P. Murphy
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Shaun R. Brinsmade
- Department of Biology, Georgetown University, Washington, DC, United States of America
- Department of Microbiology and Immunology, Georgetown University, Washington, DC, United States of America
| | - David E. Heinrichs
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
- * E-mail:
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30
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Zhu C, Xiao F, Qiu Y, Wang Q, He Z, Chen S. Lichenysin production is improved in codY null Bacillus licheniformis by addition of precursor amino acids. Appl Microbiol Biotechnol 2017; 101:6375-6383. [DOI: 10.1007/s00253-017-8352-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/15/2017] [Accepted: 05/19/2017] [Indexed: 01/31/2023]
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31
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Hajaj B, Yesilkaya H, Shafeeq S, Zhi X, Benisty R, Tchalah S, Kuipers OP, Porat N. CodY Regulates Thiol Peroxidase Expression as Part of the Pneumococcal Defense Mechanism against H 2O 2 Stress. Front Cell Infect Microbiol 2017; 7:210. [PMID: 28596944 PMCID: PMC5443158 DOI: 10.3389/fcimb.2017.00210] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 05/09/2017] [Indexed: 12/21/2022] Open
Abstract
Streptococcus pneumoniae is a facultative anaerobic pathogen. Although it maintains fermentative metabolism, during aerobic growth pneumococci produce high levels of H2O2, which can have adverse effects on cell viability and DNA, and influence pneumococcal interaction with its host. The pneumococcus is unusual in its dealing with toxic reactive oxygen species (ROS) in that it neither has catalase nor the global regulators of peroxide stress resistance. Previously, we identified pneumococcal thiol peroxidase (TpxD) as the key enzyme for enzymatic removal of H2O2, and showed that TpxD synthesis is up-regulated upon exposure to H2O2. This study aimed to reveal the mechanism controlling TpxD expression under H2O2 stress. We hypothesize that H2O2 activates a transcription factor which in turn up-regulates tpxD expression. Microarray analysis revealed a pneumococcal global transcriptional response to H2O2. Mutation of tpxD abolished H2O2-mediated response to high H2O2 levels, signifying the need for an active TpxD under oxidative stress conditions. Bioinformatic tools, applied to search for a transcription factor modulating tpxD expression, pointed toward CodY as a potential candidate. Indeed, a putative 15-bp consensus CodY binding site was found in the proximal region of tpxD-coding sequence. Binding of CodY to this site was confirmed by EMSA, and genetic engineering techniques demonstrated that this site is essential for TpxD up-regulation under H2O2 stress. Furthermore, tpxD expression was reduced in a ΔcodY mutant. These data indicate that CodY is an activator of tpxD expression, triggering its up-regulation under H2O2 stress. In addition we show that H2O2 specifically oxidizes the 2 CodY cysteines. This oxidation may trigger a conformational change in CodY, resulting in enhanced binding to DNA. A schematic model illustrating the contribution of TpxD and CodY to pneumococcal global transcriptional response to H2O2 is proposed.
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Affiliation(s)
- Barak Hajaj
- Pediatric Infectious Disease Unit, Department of Microbiology and Immunology, Faculty of Health Sciences, Soroka University Medical Center, Ben-Gurion University of the NegevBeer Sheva, Israel
| | - Hasan Yesilkaya
- Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, United Kingdom
| | - Sulman Shafeeq
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningen, Netherlands
| | - Xiangyun Zhi
- Department of Infection, Immunity and Inflammation, University of LeicesterLeicester, United Kingdom
| | - Rachel Benisty
- Pediatric Infectious Disease Unit, Department of Microbiology and Immunology, Faculty of Health Sciences, Soroka University Medical Center, Ben-Gurion University of the NegevBeer Sheva, Israel
| | - Shiran Tchalah
- Pediatric Infectious Disease Unit, Department of Microbiology and Immunology, Faculty of Health Sciences, Soroka University Medical Center, Ben-Gurion University of the NegevBeer Sheva, Israel
| | - Oscar P Kuipers
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of GroningenGroningen, Netherlands
| | - Nurith Porat
- Pediatric Infectious Disease Unit, Department of Microbiology and Immunology, Faculty of Health Sciences, Soroka University Medical Center, Ben-Gurion University of the NegevBeer Sheva, Israel
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32
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Dhali D, Coutte F, Arias AA, Auger S, Bidnenko V, Chataigné G, Lalk M, Niehren J, de Sousa J, Versari C, Jacques P. Genetic engineering of the branched fatty acid metabolic pathway ofBacillus subtilisfor the overproduction of surfactin C14isoform. Biotechnol J 2017; 12. [DOI: 10.1002/biot.201600574] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/13/2017] [Accepted: 03/31/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Debarun Dhali
- University Lille, INRA, ISA, University Artois, University Littoral Côte d'Opale; EA 7394 - ICV - Institut Charles Viollette; Lille France
| | - François Coutte
- University Lille, INRA, ISA, University Artois, University Littoral Côte d'Opale; EA 7394 - ICV - Institut Charles Viollette; Lille France
| | - Anthony Argüelles Arias
- MiPI, TERRA Research Centre, Gembloux Agro-Bio Tech; University of Liege; Passage des Déportés; Gembloux Belgium
| | - Sandrine Auger
- Micalis Institute, INRA, AgroParisTech; University Paris-Saclay; Jouy-en-Josas France
| | - Vladimir Bidnenko
- Micalis Institute, INRA, AgroParisTech; University Paris-Saclay; Jouy-en-Josas France
| | - Gabrielle Chataigné
- University Lille, INRA, ISA, University Artois, University Littoral Côte d'Opale; EA 7394 - ICV - Institut Charles Viollette; Lille France
| | - Michael Lalk
- Ernst-Moritz-Arndt-University Greifswald; Institute of Biochemistry; Greifswald Germany
| | - Joachim Niehren
- University Lille; BioComputing Team, CRIStAL Lab (CNRS UMR9189); Villeneuve d'Ascq France
- Inria Lille; Villeneuve d'Ascq France
| | - Joana de Sousa
- Ernst-Moritz-Arndt-University Greifswald; Institute of Biochemistry; Greifswald Germany
| | - Cristian Versari
- University Lille; BioComputing Team, CRIStAL Lab (CNRS UMR9189); Villeneuve d'Ascq France
| | - Philippe Jacques
- University Lille, INRA, ISA, University Artois, University Littoral Côte d'Opale; EA 7394 - ICV - Institut Charles Viollette; Lille France
- MiPI, TERRA Research Centre, Gembloux Agro-Bio Tech; University of Liege; Passage des Déportés; Gembloux Belgium
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33
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Levdikov VM, Blagova E, Young VL, Belitsky BR, Lebedev A, Sonenshein AL, Wilkinson AJ. Structure of the Branched-chain Amino Acid and GTP-sensing Global Regulator, CodY, from Bacillus subtilis. J Biol Chem 2016; 292:2714-2728. [PMID: 28011634 PMCID: PMC5314169 DOI: 10.1074/jbc.m116.754309] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 12/23/2016] [Indexed: 01/02/2023] Open
Abstract
CodY is a branched-chain amino acid (BCAA) and GTP sensor and a global regulator of transcription in low G + C Gram-positive bacteria. It controls the expression of over 100 genes and operons, principally by repressing during growth genes whose products are required for adaptations to nutrient limitation. However, the mechanism by which BCAA binding regulates transcriptional changes is not clear. It is known that CodY consists of a GAF (cGMP-stimulated phosphodiesterases, adenylate cyclases, FhlA) domain that binds BCAAs and a winged helix-turn-helix (wHTH) domain that binds to DNA, but the way in which these domains interact and the structural basis of the BCAA dependence of this interaction are unknown. To gain new insights, we determined the crystal structure of unliganded CodY from Bacillus subtilis revealing a 10-turn α-helix linking otherwise discrete GAF and wHTH domains. The structure of CodY in complex with isoleucine revealed a reorganized GAF domain. In both complexes CodY was tetrameric. Size exclusion chromatography with multiangle laser light scattering (SEC-MALLS) experiments showed that CodY is a dimer at concentrations found in bacterial cells. Comparison of structures of dimers of unliganded CodY and CodY-Ile derived from the tetramers showed a splaying of the wHTH domains when Ile was bound; splaying is likely to account for the increased affinity of Ile-bound CodY for DNA. Electrophoretic mobility shift and SEC-MALLS analyses of CodY binding to 19-36-bp operator fragments are consistent with isoleucine-dependent binding of two CodY dimers per duplex. The implications of these observations for effector control of CodY activity are discussed.
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Affiliation(s)
- Vladimir M Levdikov
- From the Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Elena Blagova
- From the Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Vicki L Young
- From the Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Boris R Belitsky
- the Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, and
| | - Andrey Lebedev
- the STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Abraham L Sonenshein
- the Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, and
| | - Anthony J Wilkinson
- From the Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom,
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34
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Kaiser JC, Sen S, Sinha A, Wilkinson BJ, Heinrichs DE. The role of two branched-chain amino acid transporters in Staphylococcus aureus growth, membrane fatty acid composition and virulence. Mol Microbiol 2016; 102:850-864. [PMID: 27589208 DOI: 10.1111/mmi.13495] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2016] [Indexed: 12/24/2022]
Abstract
The branched-chain amino acids (BCAAs) are vital to both growth and virulence of the human pathogen Staphylococcus aureus. In addition to supporting protein synthesis, the BCAAs serve as precursors for branched-chain fatty acids (BCFAs), which are predominant membrane fatty acids, and, in association with the global regulatory protein CodY, the BCAAs are key co-regulators of virulence factors. Despite these critical functions, S. aureus represses Leu and Val synthesis, instead preferring to acquire them from the extracellular milieu. We previously identified BrnQ1 as a BCAA transporter, yet a brnQ1 mutant remained capable of BCAA acquisition. Here, we describe BcaP as an additional BCAA transporter, and determine that it plays a secondary role to BrnQ1 during S. aureus growth in a chemically defined medium. Furthermore, membrane fatty acid composition analysis revealed that BrnQ1, and not BcaP, is required for transporting Leu and Val to be used for iso-BCFA synthesis. Despite a predominant role for BrnQ1 in vitro, both BrnQ1 and BcaP are required for S. aureus fitness in vivo in a hematogenous spread infection model and a nasal colonisation model. These data demonstrate the importance of BrnQ1 and BcaP for growth, environmental adaptation and virulence of S. aureus.
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Affiliation(s)
- Julienne C Kaiser
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada
| | - Suranjana Sen
- School of Biological Sciences, Illinois State University, Normal, IL, USA
| | - Anshul Sinha
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada
| | - Brian J Wilkinson
- School of Biological Sciences, Illinois State University, Normal, IL, USA
| | - David E Heinrichs
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada
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35
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Rosenberg J, Müller P, Lentes S, Thiele MJ, Zeigler DR, Tödter D, Paulus H, Brantl S, Stülke J, Commichau FM. ThrR, a DNA‐binding transcription factor involved in controlling threonine biosynthesis in
Bacillus subtilis. Mol Microbiol 2016; 101:879-93. [DOI: 10.1111/mmi.13429] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Jonathan Rosenberg
- Department of General MicrobiologyGeorg August University GöttingenGrisebachstr. 8Göttingen37077 Germany
| | - Peter Müller
- Department of GeneticsBacterial Genetics, Friedrich Schiller University JenaJena Germany
| | - Sabine Lentes
- Department of General MicrobiologyGeorg August University GöttingenGrisebachstr. 8Göttingen37077 Germany
| | - Martin J. Thiele
- Department of General MicrobiologyGeorg August University GöttingenGrisebachstr. 8Göttingen37077 Germany
| | | | - Dominik Tödter
- Department of General MicrobiologyGeorg August University GöttingenGrisebachstr. 8Göttingen37077 Germany
| | - Henry Paulus
- Boston Biomedical Research InstituteBoston MA USA
| | - Sabine Brantl
- Department of GeneticsBacterial Genetics, Friedrich Schiller University JenaJena Germany
| | - Jörg Stülke
- Department of General MicrobiologyGeorg August University GöttingenGrisebachstr. 8Göttingen37077 Germany
| | - Fabian M. Commichau
- Department of General MicrobiologyGeorg August University GöttingenGrisebachstr. 8Göttingen37077 Germany
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Sensitive change of iso-branched fatty acid (iso-15:0) in Bacillus pumilus PAMC 23174 in response to environmental changes. Bioprocess Biosyst Eng 2015; 39:159-67. [DOI: 10.1007/s00449-015-1500-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 10/29/2015] [Indexed: 11/26/2022]
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Liu X, Han Q, Xu J, Wang J, Shi J. Acetohydroxyacid synthase FgIlv2 and FgIlv6 are involved in BCAA biosynthesis, mycelial and conidial morphogenesis, and full virulence in Fusarium graminearum. Sci Rep 2015; 5:16315. [PMID: 26552344 PMCID: PMC4639788 DOI: 10.1038/srep16315] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 10/12/2015] [Indexed: 11/10/2022] Open
Abstract
In this study, we characterized FgIlv2 and FgIlv6, the catalytic and regulatory subunits of acetohydroxyacid synthase (AHAS) from the important wheat head scab fungus Fusarium graminearum. AHAS catalyzes the first common step in the parallel pathways toward branched-chain amino acids (BCAAs: isoleucine, leucine, valine) and is the inhibitory target of several commercialized herbicides. Both FgILV2 and FgILV6 deletion mutants were BCAA-auxotrophic and showed reduced aerial hyphal growth and red pigmentation when cultured on PDA plates. Conidial formation was completely blocked in the FgILV2 deletion mutant ΔFgIlv2-4 and significantly reduced in the FgILV6 deletion mutant ΔFgIlv6-12. The auxotrophs of ΔFgIlv2-4 and ΔFgIlv6-12 could be restored by exogenous addition of BCAAs but relied on the designated nitrogen source the medium contained. Deletion of FgILV2 or FgILV6 also leads to hypersensitivity to various cellular stresses and reduced deoxynivalenol production. ΔFgIlv2-4 lost virulence completely on flowering wheat heads, whereas ΔFgIlv6-12 could cause scab symptoms in the inoculated spikelet but lost its aggressiveness. Taken together, our study implies the potential value of antifungals targeting both FgIlv2 and FgIlv6 in F. graminearum.
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Affiliation(s)
- Xin Liu
- Institute of Food Quality and Safety, Jiangsu Academy of Agricultural Sciences, Jiangsu, China.,State Key Laboratory Breeding Base of Food Quality and Safety in Jiangsu Province, Jiangsu, China.,Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Jiangsu, China.,Key Laboratory of Agro-product Safety Risk Evaluation Nanjing (Ministry of Agriculture), Jiangsu, China.,Collaborative Innovation Center for Modern Grain Circulation and Safety, Jiangsu, China
| | - Qi Han
- Institute of Food Quality and Safety, Jiangsu Academy of Agricultural Sciences, Jiangsu, China
| | - Jianhong Xu
- Institute of Food Quality and Safety, Jiangsu Academy of Agricultural Sciences, Jiangsu, China.,State Key Laboratory Breeding Base of Food Quality and Safety in Jiangsu Province, Jiangsu, China.,Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Jiangsu, China.,Key Laboratory of Agro-product Safety Risk Evaluation Nanjing (Ministry of Agriculture), Jiangsu, China.,Collaborative Innovation Center for Modern Grain Circulation and Safety, Jiangsu, China
| | - Jian Wang
- Institute of Food Quality and Safety, Jiangsu Academy of Agricultural Sciences, Jiangsu, China
| | - Jianrong Shi
- Institute of Food Quality and Safety, Jiangsu Academy of Agricultural Sciences, Jiangsu, China.,State Key Laboratory Breeding Base of Food Quality and Safety in Jiangsu Province, Jiangsu, China.,Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Jiangsu, China.,Key Laboratory of Agro-product Safety Risk Evaluation Nanjing (Ministry of Agriculture), Jiangsu, China.,Collaborative Innovation Center for Modern Grain Circulation and Safety, Jiangsu, China
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Intermediate Levels of Bacillus subtilis CodY Activity Are Required for Derepression of the Branched-Chain Amino Acid Permease, BraB. PLoS Genet 2015; 11:e1005600. [PMID: 26473603 PMCID: PMC4608796 DOI: 10.1371/journal.pgen.1005600] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 09/22/2015] [Indexed: 11/22/2022] Open
Abstract
The global transcriptional regulator, CodY, binds strongly to the regulatory region of the braB gene, which encodes a Bacillus subtilis branched-chain amino acid (BCAA) permease. However, under conditions that maximize CodY activity, braB expression was similar in wild-type and codY null mutant cells. Nonetheless, expression from the braB promoter was significantly elevated in cells containing partially active mutant versions of CodY or in wild-type cells under growth conditions leading to intermediate levels of CodY activity. This novel pattern of regulation was shown to be due to two opposing mechanisms, negative and positive, by which CodY affects braB expression. A strong CodY-binding site located downstream of the transcription start point conferred negative regulation by direct interaction with CodY. Additionally, sequences upstream and downstream of the promoter were required for repression by a second pleiotropic B. subtilis regulator, ScoC, whose own expression is repressed by CodY. ScoC-mediated repression of braB in codY null mutants cells was as efficient as direct, CodY-mediated repression in wild-type cells under conditions of high CodY activity. However, under conditions of reduced CodY activity, CodY-mediated repression was relieved to a greater extent than ScoC-mediated repression was increased, leading to elevated braB expression. We conclude that restricting increased expression of braB to conditions of moderate nutrient limitation is the raison d’être of the feed-forward regulatory loop formed by CodY and ScoC at the braB promoter. The increase in BraB expression only at intermediate activities of CodY may facilitate the uptake of BCAA when they are not in excess but prevent unneeded BraB synthesis when other BCAA transporters are active. Expression of Bacillus subtilis BraB, a branched-chain amino acid permease, is under both negative and positive control by a global transcriptional regulator CodY. The negative control is direct and the positive control is indirect and mediated by another B. subtilis pleiotropic transcriptional regulator, ScoC, which, in turn, is repressed by CodY. Thus, CodY and ScoC form a feed-forward regulatory loop at the braB promoter. In a very unusual manner, the interaction of CodY and ScoC results in high braB expression only at intermediate CodY activities; braB expression remains low both at high and low CodY activities. The novel regulation of braB shows that important, novel regulatory phenomena can be missed by analyzing null mutants in regulatory genes but revealed by using mutants with partial activity.
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