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Hu M, Wang J, Gao Y, Fan B, Wang F, Li S. Proteomic Analysis of the Characteristic Flavor Components in Bacillus subtilis BSNK-5-Fermented Soymilk. Foods 2024; 13:2399. [PMID: 39123590 PMCID: PMC11311612 DOI: 10.3390/foods13152399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Revised: 07/19/2024] [Accepted: 07/25/2024] [Indexed: 08/12/2024] Open
Abstract
Fermentation with Bacillus subtilis significantly enhances the physiological activity and bioavailability of soymilk, but the resulting characteristic flavor seriously affects its industrial promotion. The objective of this study was to identify key proteins associated with characteristic flavors in B. subtilis BSNK-5-fermented soymilk using tandem mass tag (TMT) proteomics. The results showed that a total of 765 differentially expressed proteins were identified. Seventy differentially expressed proteins related to characteristic flavor were screened through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. After integrating metabolomics data, fifteen key proteases of characteristic flavor components in BSNK-5-fermented soymilk were further identified, and free ammonia was added. In addition, there were five main formation mechanisms, including the decomposition of urea to produce ammonia; the degradation of glutamate by glutamate dehydrogenase to produce ammonia; the degradation of threonine and non-enzymatic changes to form the derivative 2,5-dimethylpyrazine; the degradation of valine, leucine, and isoleucine to synthesize isovalerate and 2-methylbutyrate; and the metabolism of pyruvate and lactate to synthesize acetate. These results provide a theoretical foundation for the improvement of undesirable flavor in B. subtilis BSNK-5-fermented soy foods.
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Affiliation(s)
- Miao Hu
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (M.H.); (J.W.); (Y.G.); (B.F.)
| | - Jiao Wang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (M.H.); (J.W.); (Y.G.); (B.F.)
| | - Yaxin Gao
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (M.H.); (J.W.); (Y.G.); (B.F.)
| | - Bei Fan
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (M.H.); (J.W.); (Y.G.); (B.F.)
| | - Fengzhong Wang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (M.H.); (J.W.); (Y.G.); (B.F.)
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Shuying Li
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (M.H.); (J.W.); (Y.G.); (B.F.)
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2
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Gupta MN, Uversky VN. Moonlighting enzymes: when cellular context defines specificity. Cell Mol Life Sci 2023; 80:130. [PMID: 37093283 PMCID: PMC11073002 DOI: 10.1007/s00018-023-04781-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/13/2023] [Accepted: 04/15/2023] [Indexed: 04/25/2023]
Abstract
It is not often realized that the absolute protein specificity is an exception rather than a rule. Two major kinds of protein multi-specificities are promiscuity and moonlighting. This review discusses the idea of enzyme specificity and then focusses on moonlighting. Some important examples of protein moonlighting, such as crystallins, ceruloplasmin, metallothioniens, macrophage migration inhibitory factor, and enzymes of carbohydrate metabolism are discussed. How protein plasticity and intrinsic disorder enable the removing the distinction between enzymes and other biologically active proteins are outlined. Finally, information on important roles of moonlighting in human diseases is updated.
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Affiliation(s)
- Munishwar Nath Gupta
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology, Hauz Khas, New Delhi, 110016, India
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC07, Tampa, FL, 33612-4799, USA.
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3
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Chaudhary S, Sindhu SS, Dhanker R, Kumari A. Microbes-mediated sulphur cycling in soil: Impact on soil fertility, crop production and environmental sustainability. Microbiol Res 2023; 271:127340. [PMID: 36889205 DOI: 10.1016/j.micres.2023.127340] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 02/06/2023] [Accepted: 02/18/2023] [Indexed: 03/08/2023]
Abstract
Reduction in soil fertility and depletion of natural resources due to current intensive agricultural practices along with climate changes are the major constraints for crop productivity and global food security. Diverse microbial populations' inhabiting the soil and rhizosphere participate in biogeochemical cycling of nutrients and thereby, improve soil fertility and plant health, and reduce the adverse impact of synthetic fertilizers on the environment. Sulphur is 4th most common crucial macronutrient required by all organisms including plants, animals, humans and microorganisms. Effective strategies are required to enhance sulphur content in crops for minimizing adverse effects of sulphur deficiency on plants and humans. Various microorganisms are involved in sulphur cycling in soil through oxidation, reduction, mineralization, and immobilization, and volatalization processes of diverse sulphur compounds. Some microorganisms possess the unique ability to oxidize sulphur compounds into plant utilizable sulphate (SO42-) form. Considering the importance of sulphur as a nutrient for crops, many bacteria and fungi involved in sulphur cycling have been characterized from soil and rhizosphere. Some of these microbes have been found to positively affect plant growth and crop yield through multiple mechanisms including the enhanced mobilization of nutrients in soils (i.e., sulphate, phosphorus and nitrogen), production of growth-promoting hormones, inhibition of phytopathogens, protection against oxidative damage and mitigation of abiotic stresses. Application of these beneficial microbes as biofertilizers may reduce the conventional fertilizer application in soils. However, large-scale, well-designed, and long-term field trials are necessary to recommend the use of these microbes for increasing nutrient availability for growth and yield of crop plants. This review discusses the current knowledge regarding sulphur deficiency symptoms in plants, biogeochemical cycling of sulphur and inoculation effects of sulphur oxidizing microbes in improving plant biomass and crop yield in different crops.
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Affiliation(s)
- Suman Chaudhary
- Research Associate, EBL Laboratory, ICAR-Central Institute of Research on Buffaloes, Hisar 125001, Haryana, India.
| | - Satyavir Singh Sindhu
- Department of Microbiology, CCS Haryana Agricultural University, Hisar 125004, Haryana, India.
| | - Rinku Dhanker
- International Institute of Veterinary, Education & Research, Bahuakbarpur, Rohtak 124001, Haryana, India.
| | - Anju Kumari
- Center of Food Science and Technology, CCS Haryana Agricultural University, Hisar 125004, Haryana, India.
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Comparative RNA-Sequencing Analysis Reveals High Complexity and Heterogeneity of Transcriptomic and Immune Profiles in Hepatocellular Carcinoma Tumors of Viral (HBV, HCV) and Non-Viral Etiology. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:medicina58121803. [PMID: 36557005 PMCID: PMC9785216 DOI: 10.3390/medicina58121803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/01/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
Background and Objectives: Hepatocellular carcinoma (HCC), the most common type of primary liver cancer, is the leading cause of cancer-related mortality. It arises and progresses against fibrotic or cirrhotic backgrounds mainly due to infection with hepatitis viruses B (HBV) or C (HCV) or non-viral causes that lead to chronic inflammation and genomic changes. A better understanding of molecular and immune mechanisms in HCC subtypes is needed. Materials and Methods: To identify transcriptional changes in primary HCC tumors with or without hepatitis viral etiology, we analyzed the transcriptomes of 24 patients by next-generation sequencing. Results: We identified common and unique differentially expressed genes for each etiological tumor group and analyzed the expression of SLC, ATP binding cassette, cytochrome 450, cancer testis, and heat shock protein genes. Metascape functional enrichment analysis showed mainly upregulated cell-cycle pathways in HBV and HCV and upregulated cell response to stress in non-viral infection. GeneWalk analysis identified regulator, hub, and moonlighting genes and highlighted CCNB1, ACTN2, BRCA1, IGF1, CDK1, AURKA, AURKB, and TOP2A in the HCV group and HSF1, HSPA1A, HSP90AA1, HSPB1, HSPA5, PTK2, and AURKB in the group without viral infection as hub genes. Immune infiltrate analysis showed that T cell, cytotoxic, and natural killer cell markers were significantly more highly expressed in HCV than in non-viral tumors. Genes associated with monocyte activation had the highest expression levels in HBV, while high expression of genes involved in primary adaptive immune response and complement receptor activity characterized tumors without viral infection. Conclusions: Our comprehensive study underlines the high degree of complexity of immune profiles in the analyzed groups, which adds to the heterogeneous HCC genomic landscape. The biomarkers identified in each HCC group might serve as therapeutic targets.
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Pacheco-Sánchez D, Marín P, Molina-Fuentes Á, Marqués S. Subtle sequence differences between two interacting σ 54 -dependent regulators lead to different activation mechanisms. FEBS J 2022; 289:7582-7604. [PMID: 35816183 PMCID: PMC10084136 DOI: 10.1111/febs.16576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 06/08/2022] [Accepted: 07/10/2022] [Indexed: 12/13/2022]
Abstract
In the strictly anaerobic nitrate reducing bacterium Aromatoleum anaerobium, degradation of 1,3-dihydroxybenzene (1,3-DHB, resorcinol) is controlled by two bacterial enhancer-binding proteins (bEBPs), RedR1 and RedR2, which regulate the transcription of three σ54 -dependent promoters controlling expression of the pathway. RedR1 and RedR2 are identical over their length except for their N-terminal tail which differ in sequence and length (six and eight residues, respectively), a single change in their N-terminal domain (NTD), and nine non-identical residues in their C-terminal domain (CTD). Their NTD is composed of a GAF and a PAS domain connected by a linker helix. We show that each regulator is controlled by a different mechanism: whilst RedR1 responds to the classical NTD-mediated negative regulation that is released by the presence of its effector, RedR2 activity is constitutive and controlled through interaction with BtdS, an integral membrane subunit of hydroxyhydroquinone dehydrogenase carrying out the second step in 1,3-DHB degradation. BtdS sequesters the RedR2 regulator to the membrane through its NTD, where a four-Ile track in the PAS domain, interrupted by a Thr in RedR1, and the N-terminal tail are involved. The presence of 1,3-DHB, which is metabolized to hydroxybenzoquinone, releases RedR2 from the membrane. Most bEBPs assemble into homohexamers to activate transcription; we show that hetero-oligomer formation between RedR1 and RedR2 is favoured over homo-oligomers. However, either an NTD-truncated version of RedR1 or a full-length RedR2 are capable of promoter activation on their own, suggesting they should assemble into homohexamers in vivo. We show that promoter DNA behaves as an allosteric effector through binding the CTD to control ΔNTD-RedR1 multimerization and activity. Overall, the regulation of the 1,3-DHB anaerobic degradation pathway can be described as a novel mode of bEBP activation and assembly.
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Affiliation(s)
- Daniel Pacheco-Sánchez
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Patricia Marín
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Águeda Molina-Fuentes
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Silvia Marqués
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
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Lee HY, Yoon CK, Cho YJ, Lee JW, Lee KA, Lee WJ, Seok YJ. A mannose-sensing AraC-type transcriptional activator regulates cell-cell aggregation of Vibrio cholerae. NPJ Biofilms Microbiomes 2022; 8:65. [PMID: 35987769 PMCID: PMC9392796 DOI: 10.1038/s41522-022-00331-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 08/03/2022] [Indexed: 11/18/2022] Open
Abstract
In addition to catalyzing coupled transport and phosphorylation of carbohydrates, the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) regulates various physiological processes in most bacteria. Therefore, the transcription of genes encoding the PTS is precisely regulated by transcriptional regulators depending on substrate availability. As the distribution of the mannose-specific PTS (PTSMan) is limited to animal-associated bacteria, it has been suggested to play an important role in host-bacteria interactions. In Vibrio cholerae, mannose is known to inhibit biofilm formation. During host infection, the transcription level of the V. cholerae gene encoding the putative PTSMan (hereafter referred to as manP) significantly increases, and mutations in this gene increase host survival rate. Herein, we show that an AraC-type transcriptional regulator (hereafter referred to as ManR) acts as a transcriptional activator of the mannose operon and is responsible for V. cholerae growth and biofilm inhibition on a mannose or fructose-supplemented medium. ManR activates mannose operon transcription by facilitating RNA polymerase binding to the promoter in response to mannose 6-phosphate and, to a lesser extent, to fructose 1-phosphate. When manP or manR is impaired, the mannose-induced inhibition of biofilm formation was reversed and intestinal colonization was significantly reduced in a Drosophila melanogaster infection model. Our results show that ManR recognizes mannose and fructose in the environment and facilitates V. cholerae survival in the host.
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Affiliation(s)
- Hye-Young Lee
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Chang-Kyu Yoon
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yong-Joon Cho
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jin-Woo Lee
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kyung-Ah Lee
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Won-Jae Lee
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yeong-Jae Seok
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul, 08826, Republic of Korea.
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea.
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de Sousa-d'Auria C, Constantinesco F, Bayan N, Constant P, Tropis M, Daffé M, Graille M, Houssin C. Cg1246, a new player in mycolic acid biosynthesis in Corynebacterium glutamicum. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35394419 DOI: 10.1099/mic.0.001171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Mycolic acids are key components of the complex cell envelope of Corynebacteriales. These fatty acids, conjugated to trehalose or to arabinogalactan form the backbone of the mycomembrane. While mycolic acids are essential to the survival of some species, such as Mycobacterium tuberculosis, their absence is not lethal for Corynebacterium glutamicum, which has been extensively used as a model to depict their biosynthesis. Mycolic acids are first synthesized on the cytoplasmic side of the inner membrane and transferred onto trehalose to give trehalose monomycolate (TMM). TMM is subsequently transported to the periplasm by dedicated transporters and used by mycoloyltransferase enzymes to synthesize all the other mycolate-containing compounds. Using a random transposition mutagenesis, we recently identified a new uncharacterized protein (Cg1246) involved in mycolic acid metabolism. Cg1246 belongs to the DUF402 protein family that contains some previously characterized nucleoside phosphatases. In this study, we performed a functional and structural characterization of Cg1246. We showed that absence of the protein led to a significant reduction in the pool of TMM in C. glutamicum, resulting in a decrease in all other mycolate-containing compounds. We found that, in vitro, Cg1246 has phosphatase activity on organic pyrophosphate substrates but is most likely not a nucleoside phosphatase. Using a computational approach, we identified important residues for phosphatase activity and constructed the corresponding variants in C. glutamicum. Surprisingly complementation with these non-functional proteins fully restored the defect in TMM of the Δcg1246 mutant strain, suggesting that in vivo, the phosphatase activity is not involved in mycolic acid biosynthesis.
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Affiliation(s)
- Célia de Sousa-d'Auria
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Florence Constantinesco
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Nicolas Bayan
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Patricia Constant
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Maryelle Tropis
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Mamadou Daffé
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Marc Graille
- Laboratoire de Biologie Structurale de la Cellule (BIOC), CNRS, Ecole polytechnique, IP Paris, F-91128 Palaiseau Cedex, Paris, France
| | - Christine Houssin
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
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Kohm K, Floccari VA, Lutz VT, Nordmann B, Mittelstädt C, Poehlein A, Dragoš A, Commichau FM, Hertel R. The Bacillus phage SPβ and its relatives: a temperate phage model system reveals new strains, species, prophage integration loci, conserved proteins and lysogeny management components. Environ Microbiol 2022; 24:2098-2118. [PMID: 35293111 DOI: 10.1111/1462-2920.15964] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 03/02/2022] [Indexed: 11/28/2022]
Abstract
The Bacillus phage SPβ has been known for about 50 years, but only a few strains are available. We isolated four new wild-type strains of the SPbeta species. Phage vB_BsuS-Goe14 introduces its prophage into the spoVK locus, previously not observed to be used by SPβ-like phages. Sequence data revealed the genome replication strategy and the genome packaging mode of SPβ-like phages. We extracted 55 SPβ-like prophages from public Bacillus genomes, thereby discovering three more integration loci and one additional type of integrase. The identified prophages resemble four new species clusters and three species orphans in the genus Spbetavirus. The determined core proteome of all SPβ-like prophages consists of 38 proteins. The integration cassette proved to be not conserved, even though, present in all strains. It consists of distinct integrases. Analysis of SPβ transcriptomes revealed three conserved genes, yopQ, yopR, and yokI, to be transcribed from a dormant prophage. While yopQ and yokI could be deleted from the prophage without activating the prophage, damaging of yopR led to a clear-plaque phenotype. Under the applied laboratory conditions, the yokI mutant showed an elevated virion release implying the YokI protein being a component of the arbitrium system.
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Affiliation(s)
- Katharina Kohm
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, 01968, Germany
| | | | - Veronika T Lutz
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, 1870, Denmark
| | - Birthe Nordmann
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University, Göttingen, 37077, Germany
| | - Carolin Mittelstädt
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, 01968, Germany
| | - Anja Poehlein
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University, Göttingen, 37077, Germany
| | - Anna Dragoš
- Biotechnical Faculty, University of Ljubljana, Ljubljana, 1000, Slovenia
| | - Fabian M Commichau
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, 01968, Germany
| | - Robert Hertel
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, 01968, Germany
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Flores CL, Ariño J, Gancedo C. The N-Acetylglucosamine Kinase from Yarrowia lipolytica Is a Moonlighting Protein. Int J Mol Sci 2021; 22:ijms222313109. [PMID: 34884915 PMCID: PMC8658026 DOI: 10.3390/ijms222313109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/21/2021] [Accepted: 11/29/2021] [Indexed: 11/16/2022] Open
Abstract
In Yarrowia lipolytica, expression of the genes encoding the enzymes of the N-acetylglucosamine (NAGA) utilization pathway (NAG genes) becomes independent of the presence of NAGA in a Ylnag5 mutant lacking NAGA kinase. We addressed the question of whether the altered transcription was due to a lack of kinase activity or to a moonlighting role of this protein. Glucosamine-6-phosphate deaminase (Nag1) activity was measured as a reporter of NAG genes expression. The NGT1 gene encoding the NAGA transporter was deleted, creating a Ylnag5 ngt1 strain. In glucose cultures of this strain, Nag1 activity was similar to that of the Ylnag5 strain, ruling out the possibility that NAGA derived from cell wall turnover could trigger the derepression. Heterologous NAGA kinases were expressed in a Ylnag5 strain. Among them, the protein from Arabidopsis thaliana did not restore kinase activity but lowered Nag1 activity 4-fold with respect to a control. Expression in the Ylnag5 strain of YlNag5 variants F320S or D214V with low kinase activity caused a repression similar to that of the wild-type protein. Together, these results indicate that YlNag5 behaves as a moonlighting protein. An RNA-seq analysis revealed that the Ylnag5 mutation had a limited transcriptomic effect besides derepression of the NAG genes.
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Affiliation(s)
- Carmen-Lisset Flores
- Instituto de Investigaciones Biomédicas “Alberto Sols” CSIC-UAM, 28029 Madrid, Spain;
- Correspondence: (C.-L.F.); (J.A.)
| | - Joaquín Ariño
- Institut de Biotecnologia i Biomedicina & Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Spain
- Correspondence: (C.-L.F.); (J.A.)
| | - Carlos Gancedo
- Instituto de Investigaciones Biomédicas “Alberto Sols” CSIC-UAM, 28029 Madrid, Spain;
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Zhang C, Nie X, Zhang H, Wu Y, He H, Yang C, Jiang W, Gu Y. Functional dissection and modulation of the BirA protein for improved autotrophic growth of gas-fermenting Clostridium ljungdahlii. Microb Biotechnol 2021; 14:2072-2089. [PMID: 34291572 PMCID: PMC8449670 DOI: 10.1111/1751-7915.13884] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 06/22/2021] [Indexed: 11/28/2022] Open
Abstract
Gas-fermenting Clostridium species can convert one-carbon gases (CO2 /CO) into a variety of chemicals and fuels, showing excellent application prospects in green biological manufacturing. The discovery of crucial genes and proteins with novel functions is important for understanding and further optimization of these autotrophic bacteria. Here, we report that the Clostridium ljungdahlii BirA protein (ClBirA) plays a pleiotropic regulator role, which, together with its biotin protein ligase (BPL) activity, enables an effective control of autotrophic growth of C. ljungdahlii. The structural modulation of ClBirA, combined with the in vivo and in vitro analyses, further reveals the action mechanism of ClBirA's dual roles as well as their interaction in C. ljungdahlii. Importantly, an atypical, flexible architecture of the binding site was found to be employed by ClBirA in the regulation of a lot of essential pathway genes, thereby expanding BirA's target genes to a broader range in clostridia. Based on these findings, molecular modification of ClBirA was performed, and an improved cellular performance of C. ljungdahlii was achieved in gas fermentation. This work reveals a previously unknown potent role of BirA in gas-fermenting clostridia, providing new perspective for understanding and engineering these autotrophic bacteria.
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Affiliation(s)
- Can Zhang
- Key Laboratory of Synthetic BiologyThe State Key Laboratory of Plant Carbon‐Nitrogen AssimilationCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- University of Chinese Academy of SciencesBeijingChina
| | - Xiaoqun Nie
- Key Laboratory of Synthetic BiologyThe State Key Laboratory of Plant Carbon‐Nitrogen AssimilationCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
| | - Huan Zhang
- Key Laboratory of Synthetic BiologyThe State Key Laboratory of Plant Carbon‐Nitrogen AssimilationCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- University of Chinese Academy of SciencesBeijingChina
| | - Yuwei Wu
- Key Laboratory of Synthetic BiologyThe State Key Laboratory of Plant Carbon‐Nitrogen AssimilationCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
- University of Chinese Academy of SciencesBeijingChina
| | - Huiqi He
- Key Laboratory of Synthetic BiologyThe State Key Laboratory of Plant Carbon‐Nitrogen AssimilationCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
| | - Chen Yang
- Key Laboratory of Synthetic BiologyThe State Key Laboratory of Plant Carbon‐Nitrogen AssimilationCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
| | - Weihong Jiang
- Key Laboratory of Synthetic BiologyThe State Key Laboratory of Plant Carbon‐Nitrogen AssimilationCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
| | - Yang Gu
- Key Laboratory of Synthetic BiologyThe State Key Laboratory of Plant Carbon‐Nitrogen AssimilationCAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai200032China
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11
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Shimada T, Ogasawara H, Kobayashi I, Kobayashi N, Ishihama A. Single-Target Regulators Constitute the Minority Group of Transcription Factors in Escherichia coli K-12. Front Microbiol 2021; 12:697803. [PMID: 34220787 PMCID: PMC8249747 DOI: 10.3389/fmicb.2021.697803] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 05/28/2021] [Indexed: 11/13/2022] Open
Abstract
The identification of regulatory targets of all transcription factors (TFs) is critical for understanding the entire network of genome regulation. A total of approximately 300 TFs exist in the model prokaryote Escherichia coli K-12, but the identification of whole sets of their direct targets is impossible with use of in vivo approaches. For this end, the most direct and quick approach is to identify the TF-binding sites in vitro on the genome. We then developed and utilized the gSELEX screening system in vitro for identification of more than 150 E. coli TF-binding sites along the E. coli genome. Based on the number of predicted regulatory targets, we classified E. coli K-12 TFs into four groups, altogether forming a hierarchy ranging from a single-target TF (ST-TF) to local TFs, global TFs, and nucleoid-associated TFs controlling as many as 1,000 targets. Using the collection of purified TFs and a library of genome DNA segments from a single and the same E. coli K-12, we identified here a total of 11 novel ST-TFs, CsqR, CusR, HprR, NorR, PepA, PutA, QseA, RspR, UvrY, ZraR, and YqhC. The regulation of single-target promoters was analyzed in details for the hitherto uncharacterized QseA and RspR. In most cases, the ST-TF gene and its regulatory target genes are adjacently located on the E. coli K-12 genome, implying their simultaneous transfer in the course of genome evolution. The newly identified 11 ST-TFs and the total of 13 hitherto identified altogether constitute the minority group of TFs in E. coli K-12.
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Affiliation(s)
| | - Hiroshi Ogasawara
- Research Center for Supports to Advanced Science, Division of Gene Research, Shinshu University, Nagano, Japan.,Research Center for Fungal and Microbial Dynamism, Shinshu University, Nagano, Japan
| | - Ikki Kobayashi
- School of Agriculture, Meiji University, Kawasaki, Japan
| | - Naoki Kobayashi
- Department of Frontier Science, Hosei University, Koganei, Japan
| | - Akira Ishihama
- Department of Frontier Science, Hosei University, Koganei, Japan.,Micro-Nano Technology Research Center, Hosei University, Koganei, Japan
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12
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The expanding world of metabolic enzymes moonlighting as RNA binding proteins. Biochem Soc Trans 2021; 49:1099-1108. [PMID: 34110361 DOI: 10.1042/bst20200664] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 05/23/2021] [Accepted: 05/25/2021] [Indexed: 12/15/2022]
Abstract
RNA binding proteins play key roles in many aspects of RNA metabolism and function, including splicing, transport, translation, localization, stability and degradation. Within the past few years, proteomics studies have identified dozens of enzymes in intermediary metabolism that bind to RNA. The wide occurrence and conservation of RNA binding ability across distant branches of the evolutionary tree suggest that these moonlighting enzymes are involved in connections between intermediary metabolism and gene expression that comprise far more extensive regulatory networks than previously thought. There are many outstanding questions about the molecular structures and mechanisms involved, the effects of these interactions on enzyme and RNA functions, and the factors that regulate the interactions. The effects on RNA function are likely to be wider than regulation of translation, and some enzyme-RNA interactions have been found to regulate the enzyme's catalytic activity. Several enzyme-RNA interactions have been shown to be affected by cellular factors that change under different intracellular and environmental conditions, including concentrations of substrates and cofactors. Understanding the molecular mechanisms involved in the interactions between the enzymes and RNA, the factors involved in regulation, and the effects of the enzyme-RNA interactions on both the enzyme and RNA functions will lead to a better understanding of the role of the many newly identified enzyme-RNA interactions in connecting intermediary metabolism and gene expression.
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13
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Moonlighting in Bacillus subtilis: The Small Proteins SR1P and SR7P Regulate the Moonlighting Activity of Glyceraldehyde 3-Phosphate Dehydrogenase A (GapA) and Enolase in RNA Degradation. Microorganisms 2021; 9:microorganisms9051046. [PMID: 34066298 PMCID: PMC8152036 DOI: 10.3390/microorganisms9051046] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 12/21/2022] Open
Abstract
Moonlighting proteins are proteins with more than one function. During the past 25 years, they have been found to be rather widespread in bacteria. In Bacillus subtilis, moonlighting has been disclosed to occur via DNA, protein or RNA binding or protein phosphorylation. In addition, two metabolic enzymes, enolase and phosphofructokinase, were localized in the degradosome-like network (DLN) where they were thought to be scaffolding components. The DLN comprises the major endoribonuclease RNase Y, 3'-5' exoribonuclease PnpA, endo/5'-3' exoribonucleases J1/J2 and helicase CshA. We have ascertained that the metabolic enzyme GapA is an additional component of the DLN. In addition, we identified two small proteins that bind scaffolding components of the degradosome: SR1P encoded by the dual-function sRNA SR1 binds GapA, promotes the GapA-RNase J1 interaction and increases the RNase J1 activity. SR7P encoded by the dual-function antisense RNA SR7 binds to enolase thereby enhancing the enzymatic activity of enolase bound RNase Y. We discuss the role of small proteins in modulating the activity of two moonlighting proteins.
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14
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Riediger M, Spät P, Bilger R, Voigt K, Maček B, Hess WR. Analysis of a photosynthetic cyanobacterium rich in internal membrane systems via gradient profiling by sequencing (Grad-seq). THE PLANT CELL 2021; 33:248-269. [PMID: 33793824 PMCID: PMC8136920 DOI: 10.1093/plcell/koaa017] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 11/12/2020] [Indexed: 05/23/2023]
Abstract
Although regulatory small RNAs have been reported in photosynthetic cyanobacteria, the lack of clear RNA chaperones involved in their regulation poses a conundrum. Here, we analyzed the full complement of cellular RNAs and proteins using gradient profiling by sequencing (Grad-seq) in Synechocystis 6803. Complexes with overlapping subunits such as the CpcG1-type versus the CpcL-type phycobilisomes or the PsaK1 versus PsaK2 photosystem I pre(complexes) could be distinguished, supporting the high quality of this approach. Clustering of the in-gradient distribution profiles followed by several additional criteria yielded a short list of potential RNA chaperones that include an YlxR homolog and a cyanobacterial homolog of the KhpA/B complex. The data suggest previously undetected complexes between accessory proteins and CRISPR-Cas systems, such as a Csx1-Csm6 ribonucleolytic defense complex. Moreover, the exclusive association of either RpoZ or 6S RNA with the core RNA polymerase complex and the existence of a reservoir of inactive sigma-antisigma complexes is suggested. The Synechocystis Grad-seq resource is available online at https://sunshine.biologie.uni-freiburg.de/GradSeqExplorer/ providing a comprehensive resource for the functional assignment of RNA-protein complexes and multisubunit protein complexes in a photosynthetic organism.
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Affiliation(s)
- Matthias Riediger
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Philipp Spät
- Department of Quantitative Proteomics, Interfaculty Institute for Cell Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | - Raphael Bilger
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Karsten Voigt
- IT Administration, Institute of Biology 3, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Boris Maček
- Department of Quantitative Proteomics, Interfaculty Institute for Cell Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | - Wolfgang R Hess
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
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15
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Richts B, Lentes S, Poehlein A, Daniel R, Commichau FM. A Bacillus subtilis ΔpdxT mutant suppresses vitamin B6 limitation by acquiring mutations enhancing pdxS gene dosage and ammonium assimilation. ENVIRONMENTAL MICROBIOLOGY REPORTS 2021; 13:218-233. [PMID: 33559288 DOI: 10.1111/1758-2229.12936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/03/2021] [Indexed: 06/12/2023]
Abstract
Pyridoxal-5'-phosphate (PLP), the biologically active form of vitamin B6, serves as a cofactor for many enzymes. The Gram-positive model bacterium Bacillus subtilis synthesizes PLP via the PdxST enzyme complex, consisting of the PdxT glutaminase and the PdxS PLP synthase subunits, respectively. PdxT converts glutamine to glutamate and ammonia of which the latter is channelled to PdxS. At high extracellular ammonium concentrations, the PdxS PLP synthase subunit does not depend on PdxT. Here, we assessed the potential of a B. subtilis ΔpdxT mutant to adapt to PLP limitation at the genome level. The majority of ΔpdxT suppressors had amplified a genomic region containing the pdxS gene. We also identified mutants having acquired as yet undescribed mutations in ammonium assimilation genes, indicating that the overproduction of PdxS and the NrgA ammonium transporter partially relieve vitamin B6 limitation in a ΔpdxT mutant when extracellular ammonium is scarce. Furthermore, we found that PdxS positively affects complex colony formation in B. subtilis. The catalytic mechanism of the PdxS PLP synthase subunit could be the reason for the limited evolution of the enzyme and why we could not identify a PdxS variant producing PLP independently of PdxT at low ammonium concentrations.
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Affiliation(s)
- Björn Richts
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, Göttingen, 37077, Germany
| | - Sabine Lentes
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, Göttingen, 37077, Germany
| | - Anja Poehlein
- Department of Genomic and Applied Microbiology, Institute for Microbiology and Genetics, University of Goettingen, Göttingen, 37077, Germany
| | - Rolf Daniel
- Department of Genomic and Applied Microbiology, Institute for Microbiology and Genetics, University of Goettingen, Göttingen, 37077, Germany
| | - Fabian M Commichau
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, 01968, Germany
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16
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Chen C, Liu H, Zabad S, Rivera N, Rowin E, Hassan M, Gomez De Jesus SM, Llinás Santos PS, Kravchenko K, Mikhova M, Ketterer S, Shen A, Shen S, Navas E, Horan B, Raudsepp J, Jeffery C. MoonProt 3.0: an update of the moonlighting proteins database. Nucleic Acids Res 2021; 49:D368-D372. [PMID: 33245761 PMCID: PMC7778978 DOI: 10.1093/nar/gkaa1101] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/21/2020] [Accepted: 10/31/2020] [Indexed: 01/09/2023] Open
Abstract
MoonProt 3.0 (http://moonlightingproteins.org) is an updated open-access database storing expert-curated annotations for moonlighting proteins. Moonlighting proteins have two or more physiologically relevant distinct biochemical or biophysical functions performed by a single polypeptide chain. Here, we describe an expansion in the database since our previous report in the Database Issue of Nucleic Acids Research in 2018. For this release, the number of proteins annotated has been expanded to over 500 proteins and dozens of protein annotations have been updated with additional information, including more structures in the Protein Data Bank, compared with version 2.0. The new entries include more examples from humans, plants and archaea, more proteins involved in disease and proteins with different combinations of functions. More kinds of information about the proteins and the species in which they have multiple functions has been added, including CATH and SCOP classification of structure, known and predicted disorder, predicted transmembrane helices, type of organism, relationship of the protein to disease, and relationship of organism to cause of disease.
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Affiliation(s)
- Chang Chen
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA.,Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Haipeng Liu
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Shadi Zabad
- Department of Computer Science, McGill University, Montreal, QC, Canada
| | - Nina Rivera
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Emily Rowin
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Maheen Hassan
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | | | | | - Karyna Kravchenko
- Department of Biotechnology and Bioengineering, V. N. Karazin Kharkiv National University, IL 61002, Ukraine
| | | | - Sophia Ketterer
- Cold Spring Harbor High School, Cold Spring Harbor, NY 11724, USA
| | - Annabel Shen
- Cold Spring Harbor High School, Cold Spring Harbor, NY 11724, USA
| | - Sophia Shen
- Cold Spring Harbor High School, Cold Spring Harbor, NY 11724, USA
| | - Erin Navas
- Northport High School, Northport, NY 11768, USA
| | - Bryan Horan
- Northport High School, Northport, NY 11768, USA
| | - Jaak Raudsepp
- Cold Spring Harbor High School, Cold Spring Harbor, NY 11724, USA
| | - Constance Jeffery
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA.,Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
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17
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Hemmadi V, Biswas M. An overview of moonlighting proteins in Staphylococcus aureus infection. Arch Microbiol 2020; 203:481-498. [PMID: 33048189 PMCID: PMC7551524 DOI: 10.1007/s00203-020-02071-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/29/2020] [Accepted: 10/01/2020] [Indexed: 01/01/2023]
Abstract
Staphylococcus aureus is responsible for numerous instances of superficial, toxin-mediated, and invasive infections. The emergence of methicillin-resistant (MRSA), as well as vancomycin-resistant (VRSA) strains of S. aureus, poses a massive threat to human health. The tenacity of S. aureus to acquire resistance against numerous antibiotics in a very short duration makes the effort towards developing new antibiotics almost futile. S. aureus owes its destructive pathogenicity to the plethora of virulent factors it produces among which a majority of them are moonlighting proteins. Moonlighting proteins are the multifunctional proteins in which a single protein, with different oligomeric conformations, perform multiple independent functions in different cell compartments. Peculiarly, proteins involved in key ancestral functions and metabolic pathways typically exhibit moonlighting functions. Pathogens mainly employ those proteins as virulent factors which exhibit high structural conservation towards their host counterparts. Consequentially, the host immune system counteracts these invading bacterial virulent factors with minimal protective action. Additionally, many moonlighting proteins also play multiple roles in various stages of pathogenicity while augmenting the virulence of the bacterium. This has necessitated elaborative studies to be conducted on moonlighting proteins of S. aureus that can serve as drug targets. This review is a small effort towards understanding the role of various moonlighting proteins in the pathogenicity of S. aureus.
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Affiliation(s)
- Vijay Hemmadi
- Department of Biological Sciences, Birla Institute of Technology and Science, BITS-Pilani, K. K. Birla Goa Campus, NH17B, Zuarinagar, Goa, 403726, India
| | - Malabika Biswas
- Department of Biological Sciences, Birla Institute of Technology and Science, BITS-Pilani, K. K. Birla Goa Campus, NH17B, Zuarinagar, Goa, 403726, India.
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18
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Gibhardt J, Heidemann JL, Bremenkamp R, Rosenberg J, Seifert R, Kaever V, Ficner R, Commichau FM. An extracytoplasmic protein and a moonlighting enzyme modulate synthesis of c-di-AMP in Listeria monocytogenes. Environ Microbiol 2020; 22:2771-2791. [PMID: 32250026 DOI: 10.1111/1462-2920.15008] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 03/17/2020] [Accepted: 03/31/2020] [Indexed: 01/06/2023]
Abstract
The second messenger cyclic di-AMP (c-di-AMP) is essential for growth of many bacteria because it controls osmolyte homeostasis. c-di-AMP can regulate the synthesis of potassium uptake systems in some bacteria and it also directly inhibits and activates potassium import and export systems, respectively. Therefore, c-di-AMP production and degradation have to be tightly regulated depending on the environmental osmolarity. The Gram-positive pathogen Listeria monocytogenes relies on the membrane-bound diadenylate cyclase CdaA for c-di-AMP production and degrades the nucleotide with two phosphodiesterases. While the enzymes producing and degrading the dinucleotide have been reasonably well examined, the regulation of c-di-AMP production is not well understood yet. Here we demonstrate that the extracytoplasmic regulator CdaR interacts with CdaA via its transmembrane helix to modulate c-di-AMP production. Moreover, we show that the phosphoglucosamine mutase GlmM forms a complex with CdaA and inhibits the diadenylate cyclase activity in vitro. We also found that GlmM inhibits c-di-AMP production in L. monocytogenes when the bacteria encounter osmotic stress. Thus, GlmM is the major factor controlling the activity of CdaA in vivo. GlmM can be assigned to the class of moonlighting proteins because it is active in metabolism and adjusts the cellular turgor depending on environmental osmolarity.
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Affiliation(s)
- Johannes Gibhardt
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany.,FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, 01968, Senftenberg, Germany
| | - Jana L Heidemann
- Department of Molecular Structural Biology, Institute for Microbiology and Genetics, GZMB, University of Goettingen, 37077, Göttingen, Germany
| | - Rica Bremenkamp
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
| | - Jonathan Rosenberg
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, 37077, Göttingen, Germany
| | - Roland Seifert
- Institute of Pharmacology & Research Core Unit Metabolomics, Hannover Medical School, Hannover, Germany
| | - Volkhard Kaever
- Institute of Pharmacology & Research Core Unit Metabolomics, Hannover Medical School, Hannover, Germany
| | - Ralf Ficner
- Department of Molecular Structural Biology, Institute for Microbiology and Genetics, GZMB, University of Goettingen, 37077, Göttingen, Germany
| | - Fabian M Commichau
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, 01968, Senftenberg, Germany
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19
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Park H, McGill SL, Arnold AD, Carlson RP. Pseudomonad reverse carbon catabolite repression, interspecies metabolite exchange, and consortial division of labor. Cell Mol Life Sci 2020; 77:395-413. [PMID: 31768608 PMCID: PMC7015805 DOI: 10.1007/s00018-019-03377-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 11/04/2019] [Accepted: 11/12/2019] [Indexed: 10/25/2022]
Abstract
Microorganisms acquire energy and nutrients from dynamic environments, where substrates vary in both type and abundance. The regulatory system responsible for prioritizing preferred substrates is known as carbon catabolite repression (CCR). Two broad classes of CCR have been documented in the literature. The best described CCR strategy, referred to here as classic CCR (cCCR), has been experimentally and theoretically studied using model organisms such as Escherichia coli. cCCR phenotypes are often used to generalize universal strategies for fitness, sometimes incorrectly. For instance, extremely competitive microorganisms, such as Pseudomonads, which arguably have broader global distributions than E. coli, have achieved their success using metabolic strategies that are nearly opposite of cCCR. These organisms utilize a CCR strategy termed 'reverse CCR' (rCCR), because the order of preferred substrates is nearly reverse that of cCCR. rCCR phenotypes prefer organic acids over glucose, may or may not select preferred substrates to optimize growth rates, and do not allocate intracellular resources in a manner that produces an overflow metabolism. cCCR and rCCR have traditionally been interpreted from the perspective of monocultures, even though most microorganisms live in consortia. Here, we review the basic tenets of the two CCR strategies and consider these phenotypes from the perspective of resource acquisition in consortia, a scenario that surely influenced the evolution of cCCR and rCCR. For instance, cCCR and rCCR metabolism are near mirror images of each other; when considered from a consortium basis, the complementary properties of the two strategies can mitigate direct competition for energy and nutrients and instead establish cooperative division of labor.
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Affiliation(s)
- Heejoon Park
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, USA
- Center for Biofilm Engineering, Montana State University, Bozeman, USA
| | - S Lee McGill
- Department of Microbiology and Immunology, Montana State University, Bozeman, USA
- Center for Biofilm Engineering, Montana State University, Bozeman, USA
| | - Adrienne D Arnold
- Department of Microbiology and Immunology, Montana State University, Bozeman, USA
- Center for Biofilm Engineering, Montana State University, Bozeman, USA
| | - Ross P Carlson
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, USA.
- Department of Microbiology and Immunology, Montana State University, Bozeman, USA.
- Center for Biofilm Engineering, Montana State University, Bozeman, USA.
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20
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Niu T, Lv X, Liu Z, Li J, Du G, Liu L. Synergetic engineering of central carbon and nitrogen metabolism for the production ofN‐acetylglucosamine inBacillus subtilis. Biotechnol Appl Biochem 2020; 67:123-132. [DOI: 10.1002/bab.1845] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/23/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Tengfei Niu
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| | - Zhenmin Liu
- State Key Laboratory of Dairy BiotechnologyShanghai Engineering Research Center of Dairy BiotechnologyDairy Research InstituteBright Dairy & Food Co., Ltd. Shanghai People's Republic of China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
- Key Laboratory of Industrial BiotechnologyMinistry of EducationJiangnan University Wuxi People's Republic of China
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21
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Dormeyer M, Lentes S, Richts B, Heermann R, Ischebeck T, Commichau FM. Variants of the Bacillus subtilis LysR-Type Regulator GltC With Altered Activator and Repressor Function. Front Microbiol 2019; 10:2321. [PMID: 31649652 PMCID: PMC6794564 DOI: 10.3389/fmicb.2019.02321] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/23/2019] [Indexed: 11/20/2022] Open
Abstract
The Gram-positive soil bacterium Bacillus subtilis relies on the glutamine synthetase and the glutamate synthase for glutamate biosynthesis from ammonium and 2-oxoglutarate. During growth with the carbon source glucose, the LysR-type transcriptional regulator GltC activates the expression of the gltAB glutamate synthase genes. With excess of intracellular glutamate, the gltAB genes are not transcribed because the glutamate-degrading glutamate dehydrogenases (GDHs) inhibit GltC. Previous in vitro studies revealed that 2-oxoglutarate and glutamate stimulate the activator and repressor function, respectively, of GltC. Here, we have isolated GltC variants with enhanced activator or repressor function. The majority of the GltC variants with enhanced activator function differentially responded to the GDHs and to glutamate. The GltC variants with enhanced repressor function were still capable of activating the PgltA promoter in the absence of a GDH. Using PgltA promoter variants (PgltA∗) that are active independent of GltC, we show that the wild type GltC and the GltC variants with enhanced repressor function inactivate PgltA∗ promoters in the presence of the native GDHs. These findings suggest that GltC may also act as a repressor of the gltAB genes in vivo. We discuss a model combining previous models that were derived from in vivo and in vitro experiments.
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Affiliation(s)
- Miriam Dormeyer
- Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Sabine Lentes
- Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Björn Richts
- Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Ralf Heermann
- Institut für Molekulare Physiologie, Mikrobiologie und Weinforschung, Johannes Gutenberg-Universität Mainz, Mainz, Germany
| | - Till Ischebeck
- Department for Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Fabian M Commichau
- Department of General Microbiology, Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, Göttingen, Germany
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22
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Yus E, Lloréns-Rico V, Martínez S, Gallo C, Eilers H, Blötz C, Stülke J, Lluch-Senar M, Serrano L. Determination of the Gene Regulatory Network of a Genome-Reduced Bacterium Highlights Alternative Regulation Independent of Transcription Factors. Cell Syst 2019; 9:143-158.e13. [PMID: 31445891 PMCID: PMC6721554 DOI: 10.1016/j.cels.2019.07.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 04/14/2019] [Accepted: 06/27/2019] [Indexed: 11/30/2022]
Abstract
Here, we determined the relative importance of different transcriptional mechanisms in the genome-reduced bacterium Mycoplasma pneumoniae, by employing an array of experimental techniques under multiple genetic and environmental perturbations. Of the 143 genes tested (21% of the bacterium’s annotated proteins), only 55% showed an altered phenotype, highlighting the robustness of biological systems. We identified nine transcription factors (TFs) and their targets, representing 43% of the genome, and 16 regulators that indirectly affect transcription. Only 20% of transcriptional regulation is mediated by canonical TFs when responding to perturbations. Using a Random Forest, we quantified the non-redundant contribution of different mechanisms such as supercoiling, metabolic control, RNA degradation, and chromosome topology to transcriptional changes. Model-predicted gene changes correlate well with experimental data in 95% of the tested perturbations, explaining up to 70% of the total variance when also considering noise. This analysis highlights the importance of considering non-TF-mediated regulation when engineering bacteria. Full comprehensive reconstruction of a bacterial gene regulatory network achieved Genome-reduced bacterium Mycoplasma pneumoniae is robust to genetic perturbations Large part of transcription regulation in bacteria is transcription-factor independent Transcription-factor-independent regulation has a smaller dynamic range
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Affiliation(s)
- Eva Yus
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Doctor Aiguader 88, Barcelona 08003, Spain.
| | - Verónica Lloréns-Rico
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Doctor Aiguader 88, Barcelona 08003, Spain.
| | - Sira Martínez
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Doctor Aiguader 88, Barcelona 08003, Spain
| | - Carolina Gallo
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Doctor Aiguader 88, Barcelona 08003, Spain
| | - Hinnerk Eilers
- Department for General Microbiology, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Cedric Blötz
- Department for General Microbiology, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Jörg Stülke
- Department for General Microbiology, Georg-August-University Göttingen, 37077 Göttingen, Germany
| | - Maria Lluch-Senar
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Doctor Aiguader 88, Barcelona 08003, Spain
| | - Luis Serrano
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Doctor Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluis Companys 23, Barcelona 08010, Spain.
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23
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Chen C, Zabad S, Liu H, Wang W, Jeffery C. MoonProt 2.0: an expansion and update of the moonlighting proteins database. Nucleic Acids Res 2019; 46:D640-D644. [PMID: 29126295 PMCID: PMC5753272 DOI: 10.1093/nar/gkx1043] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 11/01/2017] [Indexed: 01/17/2023] Open
Abstract
MoonProt 2.0 (http://moonlightingproteins.org) is an updated, comprehensive and open-access database storing expert-curated annotations for moonlighting proteins. Moonlighting proteins contain two or more physiologically relevant distinct functions performed by a single polypeptide chain. Here, we describe developments in the MoonProt website and database since our previous report in the Database Issue of Nucleic Acids Research. For this V 2.0 release, we expanded the number of proteins annotated to 370 and modified several dozen protein annotations with additional or updated information, including more links to protein structures in the Protein Data Bank, compared with the previous release. The new entries include more examples from humans and several model organisms, more proteins involved in disease, and proteins with different combinations of functions. The updated web interface includes a search function using BLAST to enable users to search the database for proteins that share amino acid sequence similarity with a protein of interest. The updated website also includes additional background information about moonlighting proteins and an expanded list of links to published articles about moonlighting proteins.
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Affiliation(s)
- Chang Chen
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Shadi Zabad
- Department of Computer Science, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Haipeng Liu
- Center for Biomolecular Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Wangfei Wang
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Constance Jeffery
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA.,Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
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24
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Bervoets I, Charlier D. Diversity, versatility and complexity of bacterial gene regulation mechanisms: opportunities and drawbacks for applications in synthetic biology. FEMS Microbiol Rev 2019; 43:304-339. [PMID: 30721976 PMCID: PMC6524683 DOI: 10.1093/femsre/fuz001] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 01/21/2019] [Indexed: 12/15/2022] Open
Abstract
Gene expression occurs in two essential steps: transcription and translation. In bacteria, the two processes are tightly coupled in time and space, and highly regulated. Tight regulation of gene expression is crucial. It limits wasteful consumption of resources and energy, prevents accumulation of potentially growth inhibiting reaction intermediates, and sustains the fitness and potential virulence of the organism in a fluctuating, competitive and frequently stressful environment. Since the onset of studies on regulation of enzyme synthesis, numerous distinct regulatory mechanisms modulating transcription and/or translation have been discovered. Mostly, various regulatory mechanisms operating at different levels in the flow of genetic information are used in combination to control and modulate the expression of a single gene or operon. Here, we provide an extensive overview of the very diverse and versatile bacterial gene regulatory mechanisms with major emphasis on their combined occurrence, intricate intertwinement and versatility. Furthermore, we discuss the potential of well-characterized basal expression and regulatory elements in synthetic biology applications, where they may ensure orthogonal, predictable and tunable expression of (heterologous) target genes and pathways, aiming at a minimal burden for the host.
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Affiliation(s)
- Indra Bervoets
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Daniel Charlier
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
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25
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Regulation of arginine biosynthesis, catabolism and transport in Escherichia coli. Amino Acids 2019; 51:1103-1127. [DOI: 10.1007/s00726-019-02757-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 06/27/2019] [Indexed: 11/26/2022]
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26
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Pagani TD, Guimarães ACR, Waghabi MC, Corrêa PR, Kalume DE, Berrêdo-Pinho M, Degrave WM, Mendonça-Lima L. Exploring the Potential Role of Moonlighting Function of the Surface-Associated Proteins From Mycobacterium bovis BCG Moreau and Pasteur by Comparative Proteomic. Front Immunol 2019; 10:716. [PMID: 31080447 PMCID: PMC6497762 DOI: 10.3389/fimmu.2019.00716] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/18/2019] [Indexed: 12/14/2022] Open
Abstract
Surface-associated proteins from Mycobacterium bovis BCG Moreau RDJ are important components of the live Brazilian vaccine against tuberculosis. They are important targets during initial BCG vaccine stimulation and modulation of the host's immune response, especially in the bacterial-host interaction. These proteins might also be involved in cellular communication, chemical response to the environment, pathogenesis processes through mobility, colonization, and adherence to the host cell, therefore performing multiple functions. In this study, the proteomic profile of the surface-associated proteins from M. bovis BCG Moreau was compared to the BCG Pasteur reference strain. The methodology used was 2DE gel electrophoresis combined with mass spectrometry techniques (MALDI-TOF/TOF), leading to the identification of 115 proteins. Of these, 24 proteins showed differential expression between the two BCG strains. Furthermore, 27 proteins previously described as displaying moonlighting function were identified, 8 of these proteins showed variation in abundance comparing BCG Moreau to Pasteur and 2 of them presented two different domain hits. Moonlighting proteins are multifunctional proteins in which two or more biological functions are fulfilled by a single polypeptide chain. Therefore, the identification of such proteins with moonlighting predicted functions can contribute to a better understanding of the molecular mechanisms unleashed by live BCG Moreau RDJ vaccine components.
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Affiliation(s)
- Talita Duarte Pagani
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Ana Carolina R Guimarães
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Mariana C Waghabi
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Paloma Rezende Corrêa
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Dário Eluan Kalume
- Laboratório Interdisciplinar de Pesquisas Médicas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz-FIOCRUZ, Rio de Janeiro, Brazil.,Unidade de Espectrometria de Massas e Proteômica, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcia Berrêdo-Pinho
- Laboratório de Microbiologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Wim Maurits Degrave
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Leila Mendonça-Lima
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
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27
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Serra DO, Hengge R. A c-di-GMP-Based Switch Controls Local Heterogeneity of Extracellular Matrix Synthesis which Is Crucial for Integrity and Morphogenesis of Escherichia coli Macrocolony Biofilms. J Mol Biol 2019; 431:4775-4793. [PMID: 30954572 DOI: 10.1016/j.jmb.2019.04.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/26/2019] [Accepted: 04/01/2019] [Indexed: 12/14/2022]
Abstract
The extracellular matrix in macrocolony biofilms of Escherichia coli is arranged in a complex large-scale architecture, with homogenic matrix production close to the surface, whereas zones further below display pronounced local heterogeneity of matrix production, which results in distinct three-dimensional architectural structures. Combining genetics, cryosectioning and fluorescence microscopy of macrocolony biofilms, we demonstrate here in situ that this local matrix heterogeneity is generated by a c-di-GMP-dependent molecular switch characterized by several nested positive and negative feedback loops. In this switch, the trigger phosphodiesterase PdeR is the key component for establishing local heterogeneity in the activation of the transcription factor MlrA, which in turn activates expression of the major matrix regulator CsgD. Upon its release of direct inhibition by PdeR, the second switch component, the diguanylate cyclase DgcM, activates MlrA by direct interaction. Antagonistically acting PdeH and DgcE provide for a PdeR-sensed c-di-GMP input into this switch and-via their spatially differentially controlled expression-generate the long-range vertical asymmetry of the matrix architecture. Using flow cytometry, we show heterogeneity of CsgD expression to also occur in spatially unstructured planktonic cultures, where it is controlled by the same c-di-GMP circuitry as in macrocolony biofilms. Quantification by flow cytometry also showed CsgDON subpopulations with distinct CsgD expression levels and revealed an additional fine-tuning feedback within the PdeR/DgcM-mediated switch that depends on c-di-GMP synthesis by DgcM. Finally, local heterogeneity of matrix production was found to be crucial for the tissue-like elasticity that allows for large-scale wrinkling and folding of macrocolony biofilms.
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Affiliation(s)
- Diego O Serra
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Regine Hengge
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
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28
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Barth C, Weiss MC, Roettger M, Martin WF, Unden G. Origin and phylogenetic relationships of [4Fe-4S]-containing O 2 sensors of bacteria. Environ Microbiol 2018; 20:4567-4586. [PMID: 30225854 DOI: 10.1111/1462-2920.14411] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/10/2018] [Indexed: 11/28/2022]
Abstract
The advent of environmental O2 about 2.5 billion years ago forced microbes to metabolically adapt and to develop mechanisms for O2 sensing. Sensing of O2 by [4Fe-4S]2+ to [2Fe-2S]2+ cluster conversion represents an ancient mechanism that is used by FNREc (Escherichia coli), FNRBs (Bacillus subtilis), NreBSa (Staphylococcus aureus) and WhiB3Mt (Mycobacterium tuberculosis). The phylogenetic relationship of these sensors was investigated. FNREc homologues are restricted to the proteobacteria and a few representatives from other phyla. Homologues of FNRBs and NreBSa are located within the bacilli, of WhiB3 within the actinobacteria. Archaea contain no homologues. The data reveal no similarity between the FNREc , FNRBs , NreBSa and WhiB3 sensor families on the sequence and structural levels. These O2 sensor families arose independently in phyla that were already present at the time O2 appeared, their members were subsequently distributed by lateral gene transfer. The chemistry of [4Fe-4S] and [2Fe-2S] cluster formation and interconversion appears to be shared by the sensor protein families. The type of signal output is, however, family specific. The homologues of FNREc and NreBSa vary with regard to the number of Cys residues that coordinate the cluster. It is suggested that the variants derive from lateral gene transfer and gained other functions.
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Affiliation(s)
- C Barth
- Microbiology and Wine Research, Institute for Molecular Physiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - M C Weiss
- Institute for Molecular Evolution, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
| | - M Roettger
- Institute for Molecular Evolution, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
| | - W F Martin
- Institute for Molecular Evolution, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
| | - G Unden
- Microbiology and Wine Research, Institute for Molecular Physiology, Johannes Gutenberg University Mainz, Mainz, Germany
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29
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Reuß DR, Rath H, Thürmer A, Benda M, Daniel R, Völker U, Mäder U, Commichau FM, Stülke J. Changes of DNA topology affect the global transcription landscape and allow rapid growth of a Bacillus subtilis mutant lacking carbon catabolite repression. Metab Eng 2017; 45:171-179. [PMID: 29242163 DOI: 10.1016/j.ymben.2017.12.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 12/04/2017] [Accepted: 12/06/2017] [Indexed: 12/27/2022]
Abstract
Bacteria are able to prioritize preferred carbon sources from complex mixtures. This is achieved by the regulatory phenomenon of carbon catabolite repression. To allow the simultaneous utilization of multiple carbon sources and to prevent the time-consuming adaptation to each individual nutrient in biotechnological applications, mutants lacking carbon catabolite repression can be used. However, such mutants often exhibit pleiotropic growth defects. We have isolated and characterized mutations that overcome the growth defect of Bacillus subtilis ccpA mutants lacking the major regulator of catabolite repression, in particular their glutamate auxotrophy. Here we show, that distinct mutations affecting the essential DNA topoisomerase I (TopA) cause glutamate prototrophy of the ccpA mutant. These suppressing variants of the TopA enzyme exhibit increased activity resulting in enhanced relaxation of the DNA. Reduced DNA supercoiling results in enhanced expression of the gltAB operon encoding the biosynthetic glutamate synthase. This is achieved by a significant re-organization of the global transcription network accompanied by re-routing of metabolism, which results in inactivation of the glutamate dehydrogenase. Our results provide a link between DNA topology, the global transcriptional network, and glutamate metabolism and suggest that specific topA mutants may be well suited for biotechnological purposes.
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Affiliation(s)
- Daniel R Reuß
- Department of General Microbiology, Georg-August-University Göttingen, Göttingen, Germany
| | - Hermann Rath
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Andrea Thürmer
- Department of Genomic and Applied Microbiology, Georg-August-University Göttingen, Göttingen, Germany
| | - Martin Benda
- Department of General Microbiology, Georg-August-University Göttingen, Göttingen, Germany
| | - Rolf Daniel
- Department of Genomic and Applied Microbiology, Georg-August-University Göttingen, Göttingen, Germany; Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University Göttingen, Göttingen, Germany
| | - Uwe Völker
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Ulrike Mäder
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Fabian M Commichau
- Department of General Microbiology, Georg-August-University Göttingen, Göttingen, Germany; Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University Göttingen, Göttingen, Germany
| | - Jörg Stülke
- Department of General Microbiology, Georg-August-University Göttingen, Göttingen, Germany; Göttingen Center for Molecular Biosciences (GZMB), Georg-August-University Göttingen, Göttingen, Germany.
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30
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Hengge R. Trigger phosphodiesterases as a novel class of c-di-GMP effector proteins. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0498. [PMID: 27672149 PMCID: PMC5052742 DOI: 10.1098/rstb.2015.0498] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2016] [Indexed: 11/28/2022] Open
Abstract
The bacterial second messenger c-di-GMP controls bacterial biofilm formation, motility, cell cycle progression, development and virulence. It is synthesized by diguanylate cyclases (with GGDEF domains), degraded by specific phosphodiesterases (PDEs, with EAL of HD-GYP domains) and sensed by a wide variety of c-di-GMP-binding effectors that control diverse targets. c-di-GMP-binding effectors can be riboswitches as well as proteins with highly diverse structures and functions. The latter include ‘degenerate’ GGDEF/EAL domain proteins that are enzymatically inactive but still able to bind c-di-GMP. Surprisingly, two enzymatically active ‘trigger PDEs’, the Escherichia coli proteins PdeR and PdeL, have recently been added to this list of c-di-GMP-sensing effectors. Mechanistically, trigger PDEs are multifunctional. They directly and specifically interact with a macromolecular target (e.g. with a transcription factor or directly with a promoter region), whose activity they control by their binding and degradation of c-di-GMP—their PDE activity thus represents the c-di-GMP sensor or effector function. In this process, c-di-GMP serves as a regulatory ligand, but in contrast to classical allosteric control, this ligand is also degraded. The resulting kinetics and circuitry of control are ideally suited for trigger PDEs to serve as key components in regulatory switches. This article is part of the themed issue ‘The new bacteriology’.
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Affiliation(s)
- Regine Hengge
- Institute of Biology/Microbiology, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
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31
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Protein Moonlighting Revealed by Noncatalytic Phenotypes of Yeast Enzymes. Genetics 2017; 208:419-431. [PMID: 29127264 DOI: 10.1534/genetics.117.300377] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 11/06/2017] [Indexed: 12/19/2022] Open
Abstract
A single gene can partake in several biological processes, and therefore gene deletions can lead to different-sometimes unexpected-phenotypes. However, it is not always clear whether such pleiotropy reflects the loss of a unique molecular activity involved in different processes or the loss of a multifunctional protein. Here, using Saccharomyces cerevisiae metabolism as a model, we systematically test the null hypothesis that enzyme phenotypes depend on a single annotated molecular function, namely their catalysis. We screened a set of carefully selected genes by quantifying the contribution of catalysis to gene deletion phenotypes under different environmental conditions. While most phenotypes were explained by loss of catalysis, slow growth was readily rescued by a catalytically inactive protein in about one-third of the enzymes tested. Such noncatalytic phenotypes were frequent in the Alt1 and Bat2 transaminases and in the isoleucine/valine biosynthetic enzymes Ilv1 and Ilv2, suggesting novel "moonlighting" activities in these proteins. Furthermore, differential genetic interaction profiles of gene deletion and catalytic mutants indicated that ILV1 is functionally associated with regulatory processes, specifically to chromatin modification. Our systematic study shows that gene loss phenotypes and their genetic interactions are frequently not driven by the loss of an annotated catalytic function, underscoring the moonlighting nature of cellular metabolism.
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32
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Rodionova IA, Vetting MW, Li X, Almo SC, Osterman AL, Rodionov DA. A novel bifunctional transcriptional regulator of riboflavin metabolism in Archaea. Nucleic Acids Res 2017; 45:3785-3799. [PMID: 28073944 PMCID: PMC5397151 DOI: 10.1093/nar/gkw1331] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 12/20/2016] [Indexed: 12/11/2022] Open
Abstract
Riboflavin (vitamin B2) is the precursor of flavin mononucleotide (FMN) and flavin adenine dinucleotide, which are essential coenzymes in all free-living organisms. Riboflavin biosynthesis in many Bacteria but not in Archaea is controlled by FMN-responsive riboswitches. We identified a novel bifunctional riboflavin kinase/regulator (RbkR), which controls riboflavin biosynthesis and transport genes in major lineages of Crenarchaeota, Euryarchaeota and Thaumarchaeota. RbkR proteins are composed of the riboflavin kinase domain and a DNA-binding winged helix-turn-helix-like domain. Using comparative genomics, we predicted RbkR operator sites and reconstructed RbkR regulons in 94 archaeal genomes. While the identified RbkR operators showed significant variability between archaeal lineages, the conserved core of RbkR regulons includes riboflavin biosynthesis genes, known/predicted vitamin uptake transporters and the rbkR gene. The DNA motifs and CTP-dependent riboflavin kinase activity of two RbkR proteins were experimentally validated in vitro. The DNA binding activity of RbkR was stimulated by CTP and suppressed by FMN, a product of riboflavin kinase. The crystallographic structure of RbkR from Thermoplasma acidophilum was determined in complex with CTP and its DNA operator revealing key residues for operator and ligand recognition. Overall, this study contributes to our understanding of metabolic and regulatory networks for vitamin homeostasis in Archaea.
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Affiliation(s)
- Irina A Rodionova
- Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Matthew W Vetting
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Xiaoqing Li
- Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Steven C Almo
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Andrei L Osterman
- Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Dmitry A Rodionov
- Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA 92037, USA.,A.A. Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, 127051 Russia
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33
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Hernández MA, Lara J, Gago G, Gramajo H, Alvarez HM. The pleiotropic transcriptional regulator NlpR contributes to the modulation of nitrogen metabolism, lipogenesis and triacylglycerol accumulation in oleaginous rhodococci. Mol Microbiol 2016; 103:366-385. [DOI: 10.1111/mmi.13564] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/22/2016] [Indexed: 01/04/2023]
Affiliation(s)
- Martín A. Hernández
- INBIOP (Instituto de Biociencias de la Patagonia), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Naturales; Universidad Nacional de la Patagonia San Juan Bosco; Ruta Provincial N° 1, Km 4-Ciudad Universitaria 9000 Comodoro Rivadavia Chubut Argentina
| | - Julia Lara
- IBR (Instituto de Biología Molecular y Celular de Rosario), Consejo Nacional de Investigaciones Científicas y Técnicas. Facultad de Ciencias Bioquímicas y Farmacéuticas; Universidad Nacional de Rosario; Ocampo y Esmeralda 2000 Rosario Santa Fe Argentina
| | - Gabriela Gago
- IBR (Instituto de Biología Molecular y Celular de Rosario), Consejo Nacional de Investigaciones Científicas y Técnicas. Facultad de Ciencias Bioquímicas y Farmacéuticas; Universidad Nacional de Rosario; Ocampo y Esmeralda 2000 Rosario Santa Fe Argentina
| | - Hugo Gramajo
- IBR (Instituto de Biología Molecular y Celular de Rosario), Consejo Nacional de Investigaciones Científicas y Técnicas. Facultad de Ciencias Bioquímicas y Farmacéuticas; Universidad Nacional de Rosario; Ocampo y Esmeralda 2000 Rosario Santa Fe Argentina
| | - Héctor M. Alvarez
- INBIOP (Instituto de Biociencias de la Patagonia), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Naturales; Universidad Nacional de la Patagonia San Juan Bosco; Ruta Provincial N° 1, Km 4-Ciudad Universitaria 9000 Comodoro Rivadavia Chubut Argentina
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34
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Perchat S, Talagas A, Poncet S, Lazar N, Li de la Sierra-Gallay I, Gohar M, Lereclus D, Nessler S. How Quorum Sensing Connects Sporulation to Necrotrophism in Bacillus thuringiensis. PLoS Pathog 2016; 12:e1005779. [PMID: 27483473 PMCID: PMC4970707 DOI: 10.1371/journal.ppat.1005779] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 06/29/2016] [Indexed: 11/28/2022] Open
Abstract
Bacteria use quorum sensing to coordinate adaptation properties, cell fate or commitment to sporulation. The infectious cycle of Bacillus thuringiensis in the insect host is a powerful model to investigate the role of quorum sensing in natural conditions. It is tuned by communication systems regulators belonging to the RNPP family and directly regulated by re-internalized signaling peptides. One such RNPP regulator, NprR, acts in the presence of its cognate signaling peptide NprX as a transcription factor, regulating a set of genes involved in the survival of these bacteria in the insect cadaver. Here, we demonstrate that, in the absence of NprX and independently of its transcriptional activator function, NprR negatively controls sporulation. NprR inhibits expression of Spo0A-regulated genes by preventing the KinA-dependent phosphorylation of the phosphotransferase Spo0F, thus delaying initiation of the sporulation process. This NprR function displays striking similarities with the Rap proteins, which also belong to the RNPP family, but are devoid of DNA-binding domain and indirectly control gene expression via protein-protein interactions in Bacilli. Conservation of the Rap residues directly interacting with Spo0F further suggests a common inhibition of the sporulation phosphorelay. The crystal structure of apo NprR confirms that NprR displays a highly flexible Rap-like structure. We propose a molecular regulatory mechanism in which key residues of the bifunctional regulator NprR are directly and alternatively involved in its two functions. NprX binding switches NprR from a dimeric inhibitor of sporulation to a tetrameric transcriptional activator involved in the necrotrophic lifestyle of B. thuringiensis. NprR thus tightly coordinates sporulation and necrotrophism, ensuring survival and dissemination of the bacteria during host infection. Bacillus thuringiensis is an entomopathogenic bacterium used worldwide as biopesticide. Its life cycle in insect larvae, which includes virulence, necrotrophism and sporulation, is regulated by cell-cell communication systems involving sensor proteins directly regulated by re-internalized peptide pheromones. After toxaemia caused by pore-forming Cry toxins, the PlcR sensor activates the production of virulence factors leading to insect death. B. thuringiensis then shifts to a necrotrophic lifestyle preceding sporulation. Previously, we showed that this process is regulated by the sensor NprR, which, in the presence of its cognate signaling peptide NprX, adopts a tetrameric conformation allowing its binding to specific DNA sequences and transcription of genes involved in survival of the bacteria in insect cadavers. Here, we demonstrate that, in the absence of NprX, NprR is a dimer, which negatively controls sporulation, independently of its transcription factor activity. We show that NprR prevents the phosphorylation of the phosphoprotein Spo0F and inhibits the phosphorylation cascade regulating sporulation. This demonstrates that NprX binding switches the bifunctional sensor NprR from a dimeric sporulation inhibitor to a tetrameric transcription factor. By establishing a close coordination between cell density, necrotrophism and sporulation, this communication system benefits a pathogenic bacterium feeding on death matter like B. thuringiensis. NprR is found in all strains of the B. cereus group, including B. anthracis and B. cereus involved in food poisoning. Our results may provide new insights for controlling the development and the survival of these undesirable bacteria.
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Affiliation(s)
- Stéphane Perchat
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Antoine Talagas
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Sandrine Poncet
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Noureddine Lazar
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Inès Li de la Sierra-Gallay
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Michel Gohar
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Didier Lereclus
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
- * E-mail: (DL); (SN)
| | - Sylvie Nessler
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
- * E-mail: (DL); (SN)
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Levati E, Sartini S, Ottonello S, Montanini B. Dry and wet approaches for genome-wide functional annotation of conventional and unconventional transcriptional activators. Comput Struct Biotechnol J 2016; 14:262-70. [PMID: 27453771 PMCID: PMC4941109 DOI: 10.1016/j.csbj.2016.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/21/2016] [Accepted: 06/23/2016] [Indexed: 02/06/2023] Open
Abstract
Transcription factors (TFs) are master gene products that regulate gene expression in response to a variety of stimuli. They interact with DNA in a sequence-specific manner using a variety of DNA-binding domain (DBD) modules. This allows to properly position their second domain, called "effector domain", to directly or indirectly recruit positively or negatively acting co-regulators including chromatin modifiers, thus modulating preinitiation complex formation as well as transcription elongation. At variance with the DBDs, which are comprised of well-defined and easily recognizable DNA binding motifs, effector domains are usually much less conserved and thus considerably more difficult to predict. Also not so easy to identify are the DNA-binding sites of TFs, especially on a genome-wide basis and in the case of overlapping binding regions. Another emerging issue, with many potential regulatory implications, is that of so-called "moonlighting" transcription factors, i.e., proteins with an annotated function unrelated to transcription and lacking any recognizable DBD or effector domain, that play a role in gene regulation as their second job. Starting from bioinformatic and experimental high-throughput tools for an unbiased, genome-wide identification and functional characterization of TFs (especially transcriptional activators), we describe both established (and usually well affordable) as well as newly developed platforms for DNA-binding site identification. Selected combinations of these search tools, some of which rely on next-generation sequencing approaches, allow delineating the entire repertoire of TFs and unconventional regulators encoded by the any sequenced genome.
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Affiliation(s)
| | | | - Simone Ottonello
- Corresponding author at: Department of Life Sciences, University of Parma, Parco Area delle Scienze 23/A, 43124 Parma, Italy.Department of Life SciencesUniversity of ParmaParco Area delle Scienze 23/AParma43124Italy
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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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Nguyen Le Minh P, Nadal M, Charlier D. The trigger enzyme PepA (aminopeptidase A) ofEscherichia coli, a transcriptional repressor that generates positive supercoiling. FEBS Lett 2016; 590:1816-25. [DOI: 10.1002/1873-3468.12224] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 05/13/2016] [Accepted: 05/18/2016] [Indexed: 01/13/2023]
Affiliation(s)
- Phu Nguyen Le Minh
- Research Group of Microbiology; Department of Bioengineering Sciences; Vrije Universiteit Brussel; Belgium
| | - Marc Nadal
- Institut Jacques Monod; CNRS-Université Paris Diderot; Paris Cedex 13 France
| | - Daniel Charlier
- Research Group of Microbiology; Department of Bioengineering Sciences; Vrije Universiteit Brussel; Belgium
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Levati E, Sartini S, Bolchi A, Ottonello S, Montanini B. Moonlighting transcriptional activation function of a fungal sulfur metabolism enzyme. Sci Rep 2016; 6:25165. [PMID: 27121330 PMCID: PMC4848566 DOI: 10.1038/srep25165] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 04/11/2016] [Indexed: 01/18/2023] Open
Abstract
Moonlighting proteins, including metabolic enzymes acting as transcription factors (TF), are present in a variety of organisms but have not been described in higher fungi so far. In a previous genome-wide analysis of the TF repertoire of the plant-symbiotic fungus Tuber melanosporum, we identified various enzymes, including the sulfur-assimilation enzyme phosphoadenosine-phosphosulfate reductase (PAPS-red), as potential transcriptional activators. A functional analysis performed in the yeast Saccharomyces cerevisiae, now demonstrates that a specific variant of this enzyme, PAPS-red A, localizes to the nucleus and is capable of transcriptional activation. TF moonlighting, which is not present in the other enzyme variant (PAPS-red B) encoded by the T. melanosporum genome, relies on a transplantable C-terminal polypeptide containing an alternating hydrophobic/hydrophilic amino acid motif. A similar moonlighting activity was demonstrated for six additional proteins, suggesting that multitasking is a relatively frequent event. PAPS-red A is sulfur-state-responsive and highly expressed, especially in fruitbodies, and likely acts as a recruiter of transcription components involved in S-metabolism gene network activation. PAPS-red B, instead, is expressed at low levels and localizes to a highly methylated and silenced region of the genome, hinting at an evolutionary mechanism based on gene duplication, followed by epigenetic silencing of this non-moonlighting gene variant.
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Affiliation(s)
- Elisabetta Levati
- Biochemistry and Molecular Biology Unit, Laboratory of Functional Genomics and Protein Engineering, Department of Life Sciences, University of Parma, Parco Area delle Scienze 23/A, 43124 Parma, Italy
| | - Sara Sartini
- Biochemistry and Molecular Biology Unit, Laboratory of Functional Genomics and Protein Engineering, Department of Life Sciences, University of Parma, Parco Area delle Scienze 23/A, 43124 Parma, Italy
| | - Angelo Bolchi
- Biochemistry and Molecular Biology Unit, Laboratory of Functional Genomics and Protein Engineering, Department of Life Sciences, University of Parma, Parco Area delle Scienze 23/A, 43124 Parma, Italy
| | - Simone Ottonello
- Biochemistry and Molecular Biology Unit, Laboratory of Functional Genomics and Protein Engineering, Department of Life Sciences, University of Parma, Parco Area delle Scienze 23/A, 43124 Parma, Italy
| | - Barbara Montanini
- Biochemistry and Molecular Biology Unit, Laboratory of Functional Genomics and Protein Engineering, Department of Life Sciences, University of Parma, Parco Area delle Scienze 23/A, 43124 Parma, Italy
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Abstract
Virulence gene expression serves two main functions, growth in/on the host, and the acquisition of nutrients. Therefore, it is obvious that nutrient availability is important to control expression of virulence genes. In any cell, enzymes are the components that are best informed about the availability of their respective substrates and products. It is thus not surprising that bacteria have evolved a variety of strategies to employ this information in the control of gene expression. Enzymes that have a second (so-called moonlighting) function in the regulation of gene expression are collectively referred to as trigger enzymes. Trigger enzymes may have a second activity as a direct regulatory protein that can bind specific DNA or RNA targets under particular conditions or they may affect the activity of transcription factors by covalent modification or direct protein-protein interaction. In this chapter, we provide an overview on these mechanisms and discuss the relevance of trigger enzymes for virulence gene expression in bacterial pathogens.
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Bacterial Networks in Cells and Communities. J Mol Biol 2015; 427:3785-92. [PMID: 26506266 DOI: 10.1016/j.jmb.2015.10.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 10/21/2015] [Accepted: 10/21/2015] [Indexed: 01/26/2023]
Abstract
Research on the bacterial regulatory networks is currently experiencing a true revival, driven by advances in methodology and by emergence of novel concepts. The biannual conference Bacterial Networks (BacNet15) held in May 2015, in Sant Feliu de Guíxols, Spain, covered progress in the studies of regulatory networks that control bacterial physiology, cell biology, stress responses, metabolism, collective behavior and evolution. It demonstrated how interdisciplinary approaches that combine molecular biology and biochemistry with the latest microscopy developments, whole cell (-omics) approaches and mathematical modeling can help understand design principles relevant in microbiology. It further showed how current biotechnology and medical microbiology could profit from our knowledge of and ability to engineer regulatory networks of bacteria.
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Expression and Genetic Activation of Cyclic Di-GMP-Specific Phosphodiesterases in Escherichia coli. J Bacteriol 2015; 198:448-62. [PMID: 26553851 DOI: 10.1128/jb.00604-15] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 11/02/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Intracellular levels of the bacterial second messenger cyclic di-GMP (c-di-GMP) are controlled by antagonistic activities of diguanylate cyclases and phosphodiesterases. The phosphodiesterase PdeH was identified as a key regulator of motility in Escherichia coli, while deletions of any of the other 12 genes encoding potential phosphodiesterases did not interfere with motility. To analyze the roles of E. coli phosphodiesterases, we demonstrated that most of these proteins are expressed under laboratory conditions. We next isolated suppressor mutations in six phosphodiesterase genes, which reinstate motility in the absence of PdeH by reducing cellular levels of c-di-GMP. Expression of all mutant alleles also led to a reduction of biofilm formation. Thus, all of these proteins are bona fide phosphodiesterases that are capable of interfering with different c-di-GMP-responsive output systems by affecting the global c-di-GMP pool. This argues that E. coli possesses several phosphodiesterases that are inactive under laboratory conditions because they lack appropriate input signals. Finally, one of these phosphodiesterases, PdeL, was studied in more detail. We demonstrated that this protein acts as a transcription factor to control its own expression. Motile suppressor alleles led to a strong increase of PdeL activity and elevated pdeL transcription, suggesting that enzymatic activity and transcriptional control are coupled. In agreement with this, we showed that overall cellular levels of c-di-GMP control pdeL transcription and that this control depends on PdeL itself. We thus propose that PdeL acts both as an enzyme and as a c-di-GMP sensor to couple transcriptional activity to the c-di-GMP status of the cell. IMPORTANCE Most bacteria possess multiple diguanylate cyclases and phosphodiesterases. Genetic studies have proposed that these enzymes show signaling specificity by contributing to distinct cellular processes without much cross talk. Thus, spatial separation of individual c-di-GMP signaling units was postulated. However, since most cyclases and phosphodiesterases harbor N-terminal signal input domains, it is equally possible that most of these enzymes lack their activating signals under laboratory conditions, thereby simulating signaling specificity on a genetic level. We demonstrate that a subset of E. coli phosphodiesterases can be activated genetically to affect the global c-di-GMP pool and thus influence different c-di-GMP-dependent processes. Although this does not exclude spatial confinement of individual phosphodiesterases, this study emphasizes the importance of environmental signals for activation of phosphodiesterases.
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Feng J, Gu Y, Quan Y, Cao M, Gao W, Zhang W, Wang S, Yang C, Song C. Improved poly-γ-glutamic acid production in Bacillus amyloliquefaciens by modular pathway engineering. Metab Eng 2015; 32:106-115. [DOI: 10.1016/j.ymben.2015.09.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 09/10/2015] [Accepted: 09/11/2015] [Indexed: 12/13/2022]
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Jeffery CJ. Protein species and moonlighting proteins: Very small changes in a protein's covalent structure can change its biochemical function. J Proteomics 2015; 134:19-24. [PMID: 26455812 DOI: 10.1016/j.jprot.2015.10.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 09/23/2015] [Accepted: 10/01/2015] [Indexed: 02/03/2023]
Abstract
UNLABELLED In the past few decades, hundreds of moonlighting proteins have been identified that perform two or more distinct and physiologically relevant biochemical or biophysical functions that are not due to gene fusions, multiple RNA splice variants, or pleiotropic effects. For this special issue on protein species, this article discusses three topics related to moonlighting proteins that illustrate how small changes or differences in protein covalent structures can result in different functions. Examples are given of moonlighting proteins that switch between functions after undergoing post-translational modifications (PTMs), proteins that share high levels of amino acid sequence identity to a moonlighting protein but share only one of its functions, and several "neomorphic moonlighting proteins" in which a single amino acid mutation results in the addition of a new function. BIOLOGICAL SIGNIFICANCE For this special issue on protein species, this article discusses three topics related to moonlighting proteins : Post-translational modifications (PTMs) that can cause a switch between functions, homologs that share only one of multiple functions, and proteins in which a single amino acid mutation results in the creation of a new function. The examples included illustrate that even in an average protein of hundreds of amino acids, a relatively small difference in sequence or PTMs can result in a large difference in function, which can be important in predicting protein functions, regulation of protein functions, and in the evolution of new functions.
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Affiliation(s)
- Constance J Jeffery
- Dept. Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA; University of Illinois at Chicago, Dept. Biological Sciences, MC567, 900 S. Ashland Ave., Chicago, IL 60607, USA.
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Affiliation(s)
- Constance J. Jeffery
- Department of Biological Sciences, University of Illinois at ChicagoChicago, IL, USA
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45
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Waldrop GL. The role of symmetry in the regulation of bacterial carboxyltransferase. Biomol Concepts 2015; 2:47-52. [PMID: 25962018 DOI: 10.1515/bmc.2011.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Carboxyltransferase is one component of the multifunctional enzyme acetyl-CoA carboxylase which catalyzes the first committed step in fatty acid biosynthesis. Carboxyltransferase is an α2β2 heterotetramer and possesses two distinct but integrated functions. One function catalyzes the transfer of carbon dioxide from biotin to acetyl-CoA, whereas the other involves binding to the mRNA encoding both subunits. When carboxyltransferase binds to the mRNA both enzymatic activity and translation of the mRNA are inhibited. However, the substrate acetyl-CoA competes with mRNA for binding. Thus, mRNA binding by carboxyltransferase provides an effective mechanism for regulating enzymatic activity and gene expression. This conceptual review takes the position that regulation of enzymatic activity and gene expression of carboxyltransferase by binding to its own mRNA is at its most fundamental level the result of the symmetry in the chemical reaction catalyzed by the enzyme. The chemical reaction is symmetrical in that both substrates generate enolate anions during the course of catalysis. The chemical symmetry led to a structural symmetry in the enzyme where both the α and β subunits contain oxyanion holes that stabilize the enolate anions. Then the region of the mRNA that codes for the oxyanion holes provided the binding sites for carboxyltransferase. Thus, the symmetry of the chemical reaction formed the foundation for the evolution of the mechanism for regulation of carboxyltransferase.
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46
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Stannek L, Thiele MJ, Ischebeck T, Gunka K, Hammer E, Völker U, Commichau FM. Evidence for synergistic control of glutamate biosynthesis by glutamate dehydrogenases and glutamate inBacillus subtilis. Environ Microbiol 2015; 17:3379-90. [DOI: 10.1111/1462-2920.12813] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 02/04/2015] [Accepted: 02/11/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Lorena Stannek
- Department of General Microbiology; Institute of Microbiology and Genetics; Georg-August-University Göttingen; Grisebachstr. 8 Göttingen D-37077 Germany
| | - Martin J. Thiele
- Department of General Microbiology; Institute of Microbiology and Genetics; Georg-August-University Göttingen; Grisebachstr. 8 Göttingen D-37077 Germany
| | - Till Ischebeck
- Department for Plant Biochemistry; Albrecht-von-Haller-Institute for Plant Sciences; Georg-August-University Göttingen; Grisebachstr. 8 Göttingen D-37077 Germany
| | - Katrin Gunka
- Department of General Microbiology; Institute of Microbiology and Genetics; Georg-August-University Göttingen; Grisebachstr. 8 Göttingen D-37077 Germany
| | - Elke Hammer
- Interfaculty Institute for Genetics and Functional Genomics; University Medicine Greifswald; Friedrich-Ludwig-Jahnstr. 15a Greifswald D-17475 Germany
| | - Uwe Völker
- Interfaculty Institute for Genetics and Functional Genomics; University Medicine Greifswald; Friedrich-Ludwig-Jahnstr. 15a Greifswald D-17475 Germany
| | - Fabian M. Commichau
- Department of General Microbiology; Institute of Microbiology and Genetics; Georg-August-University Göttingen; Grisebachstr. 8 Göttingen D-37077 Germany
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47
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Campanini B, Benoni R, Bettati S, Beck CM, Hayes CS, Mozzarelli A. Moonlighting O-acetylserine sulfhydrylase: New functions for an old protein. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1854:1184-93. [PMID: 25731080 DOI: 10.1016/j.bbapap.2015.02.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/18/2015] [Accepted: 02/20/2015] [Indexed: 12/13/2022]
Abstract
O-acetylserine sulfhydrylase A (CysK) is the pyridoxal 5'-phosphate-dependent enzyme that catalyzes the final reaction of cysteine biosynthesis in bacteria. CysK was initially identified in a complex with serine acetyltransferase (CysE), which catalyzes the penultimate reaction in the synthetic pathway. This "cysteine synthase" complex is stabilized by insertion of the CysE C-terminus into the active-site of CysK. Remarkably, the CysK/CysE binding interaction is conserved in most bacterial and plant systems. For the past 40years, CysK was thought to function exclusively in cysteine biosynthesis, but recent studies have revealed a repertoire of additional "moonlighting" activities for this enzyme. CysK and its paralogs influence transcription in both Gram-positive bacteria and the nematode Caenorhabditis elegans. CysK also activates an antibacterial nuclease toxin produced by uropathogenic Escherichia coli. Intriguingly, each moonlighting activity requires a binding partner that invariably mimics the C-terminus of CysE to interact with the CysK active site. This article is part of a Special Issue entitled: Cofactor-dependent proteins: evolution, chemical diversity and bio-applications.
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Affiliation(s)
| | - Roberto Benoni
- Dipartimento di Neuroscienze, Università di Parma, Parma, Italy
| | - Stefano Bettati
- Dipartimento di Neuroscienze, Università di Parma, Parma, Italy; National Institute of Biostructures and Biosystems, Rome, Italy
| | - Christina M Beck
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA
| | - Christopher S Hayes
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA, USA.
| | - Andrea Mozzarelli
- Dipartimento di Farmacia, Università di Parma, Parma, Italy; National Institute of Biostructures and Biosystems, Rome, Italy; Institute of Biophysics, CNR, Pisa, Italy
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Marx P, Meiers M, Brückner R. Activity of the response regulator CiaR in mutants of Streptococcus pneumoniae R6 altered in acetyl phosphate production. Front Microbiol 2015; 5:772. [PMID: 25642214 PMCID: PMC4295557 DOI: 10.3389/fmicb.2014.00772] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Accepted: 12/17/2014] [Indexed: 11/25/2022] Open
Abstract
The two-component regulatory system (TCS) CiaRH of Streptococcus pneumoniae is implicated in competence, ß-lactam resistance, maintenance of cell integrity, bacteriocin production, host colonization, and virulence. Depending on the growth conditions, CiaR can be highly active in the absence of its cognate kinase CiaH, although phosphorylation of CiaR is required for DNA binding and gene regulation. To test the possibility that acetyl phosphate (AcP) could be the alternative phosphodonor, genes involved in pyruvate metabolism were disrupted to alter cellular levels of acetyl phosphate. Inactivating the genes of pyruvate oxidase SpxB, phosphotransacetylase Pta, and acetate kinase AckA, resulted in very low AcP levels and in strongly reduced CiaR-mediated gene expression in CiaH-deficient strains. Therefore, alternative phosphorylation of CiaR appears to proceed via AcP. The AcP effect on CiaR is not detected in strains with CiaH. Attempts to obtain elevated AcP by preventing its degradation by acetate kinase AckA, were not successful in CiaH-deficient strains with a functional SpxB, the most important enzyme for AcP production in S. pneumoniae. The ciaH-spxB-ackA mutant producing intermediate amounts of AcP could be constructed and showed a promoter activation, which was much higher than expected. Since activation was dependent on AcP, it can apparently be used more efficiently for CiaR phosphorylation in the absence of AckA. Therefore, high AcP levels in the absence of CiaH and AckA may cause extreme overexpression of the CiaR regulon leading to synthetic lethality. AckA is also involved in a regulatory response, which is mediated by CiaH. Addition of acetate to the growth medium switch CiaH from kinase to phosphatase. This switch is lost in the absence of AckA indicating metabolism of acetate is required, which starts with the production of AcP by AckA. Therefore, AckA plays a special regulatory role in the control of the CiaRH TCS.
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Affiliation(s)
- Patrick Marx
- Department of Microbiology, University of Kaiserslautern Kaiserslautern, Germany
| | - Marina Meiers
- Department of Microbiology, University of Kaiserslautern Kaiserslautern, Germany
| | - Reinhold Brückner
- Department of Microbiology, University of Kaiserslautern Kaiserslautern, Germany
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Mani M, Chen C, Amblee V, Liu H, Mathur T, Zwicke G, Zabad S, Patel B, Thakkar J, Jeffery CJ. MoonProt: a database for proteins that are known to moonlight. Nucleic Acids Res 2014; 43:D277-82. [PMID: 25324305 PMCID: PMC4384022 DOI: 10.1093/nar/gku954] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Moonlighting proteins comprise a class of multifunctional proteins in which a single polypeptide chain performs multiple biochemical functions that are not due to gene fusions, multiple RNA splice variants or pleiotropic effects. The known moonlighting proteins perform a variety of diverse functions in many different cell types and species, and information about their structures and functions is scattered in many publications. We have constructed the manually curated, searchable, internet-based MoonProt Database (http://www.moonlightingproteins.org) with information about the over 200 proteins that have been experimentally verified to be moonlighting proteins. The availability of this organized information provides a more complete picture of what is currently known about moonlighting proteins. The database will also aid researchers in other fields, including determining the functions of genes identified in genome sequencing projects, interpreting data from proteomics projects and annotating protein sequence and structural databases. In addition, information about the structures and functions of moonlighting proteins can be helpful in understanding how novel protein functional sites evolved on an ancient protein scaffold, which can also help in the design of proteins with novel functions.
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Affiliation(s)
- Mathew Mani
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Chang Chen
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Vaishak Amblee
- Department of Biological Sciences, MC567, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Haipeng Liu
- Center for Pharmaceutical Biotechnology, College of Pharmacy, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Tanu Mathur
- Department of Biological Sciences, MC567, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Grant Zwicke
- Department of Biological Sciences, MC567, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Shadi Zabad
- Illinois Institute of Technology, 3300 S Federal St, Chicago, IL 60616, USA
| | - Bansi Patel
- Department of Biological Sciences, MC567, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Jagravi Thakkar
- Department of Biological Sciences, MC567, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Constance J Jeffery
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA Department of Biological Sciences, MC567, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
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50
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Royce LA, Boggess E, Fu Y, Liu P, Shanks JV, Dickerson J, Jarboe LR. Transcriptomic analysis of carboxylic acid challenge in Escherichia coli: beyond membrane damage. PLoS One 2014; 9:e89580. [PMID: 24586888 PMCID: PMC3938484 DOI: 10.1371/journal.pone.0089580] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 01/21/2014] [Indexed: 11/18/2022] Open
Abstract
Carboxylic acids are an attractive biorenewable chemical. Enormous progress has been made in engineering microbes for production of these compounds though titers remain lower than desired. Here we used transcriptome analysis of Escherichia coli during exogenous challenge with octanoic acid (C8) at pH 7.0 to probe mechanisms of toxicity. This analysis highlights the intracellular acidification and membrane damage caused by C8 challenge. Network component analysis identified transcription factors with altered activity including GadE, the activator of the glutamate-dependent acid resistance system (AR2) and Lrp, the amino acid biosynthesis regulator. The intracellular acidification was quantified during exogenous challenge, but was not observed in a carboxylic acid producing strain, though this may be due to lower titers than those used in our exogenous challenge studies. We developed a framework for predicting the proton motive force during adaptation to strong inorganic acids and carboxylic acids. This model predicts that inorganic acid challenge is mitigated by cation accumulation, but that carboxylic acid challenge inverts the proton motive force and requires anion accumulation. Utilization of native acid resistance systems was not useful in terms of supporting growth or alleviating intracellular acidification. AR2 was found to be non-functional, possibly due to membrane damage. We proposed that interaction of Lrp and C8 resulted in repression of amino acid biosynthesis. However, this hypothesis was not supported by perturbation of lrp expression or amino acid supplementation. E. coli strains were also engineered for altered cyclopropane fatty acid content in the membrane, which had a dramatic effect on membrane properties, though C8 tolerance was not increased. We conclude that achieving higher production titers requires circumventing the membrane damage. As higher titers are achieved, acidification may become problematic.
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Affiliation(s)
- Liam A. Royce
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa, United States of America
| | - Erin Boggess
- Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa, United States of America
| | - Yao Fu
- Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa, United States of America
| | - Ping Liu
- Interdepartmental Microbiology Program, Iowa State University, Ames, Iowa, United States of America
| | - Jacqueline V. Shanks
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa, United States of America
| | - Julie Dickerson
- Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa, United States of America
| | - Laura R. Jarboe
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa, United States of America
- Interdepartmental Microbiology Program, Iowa State University, Ames, Iowa, United States of America
- * E-mail:
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