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Jerez SA, Mora AY, Millanao AR, Saavedra CP, Bucarey SA, Mora GC, Villagra NA, Hidalgo AA. Transcriptional regulator MarT negatively regulates MarT-regulated motility gene I, a new gene involved in invasion and virulence of Salmonella enterica. Front Microbiol 2024; 15:1430982. [PMID: 39211323 PMCID: PMC11358694 DOI: 10.3389/fmicb.2024.1430982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 06/24/2024] [Indexed: 09/04/2024] Open
Abstract
The speciation of Salmonella occurred by acquisition of genomic islands from other bacterial species and continued to diverge into subspecies and serovars with diferent range of host. S. enterica serovar Typhimurium (STM) is a generalist pathogen infecting hosts that include birds, mice, and humans, whilst S. enterica serovar Typhi (STY) is a restricted-host pathogen, infecting only humans. Despite their ranges of hosts, STM and STY possess 97-98% identity. Gain of genes by horizontal transference and loss of genes by mutations, are believed essential for differentiation of Salmonella. Salmonella pathogenicity island 3 (SPI-3) is an example combining these two processes. SPI-3 encodes misL and marT, among other genes. In STM, misL is required for gut colonization. Furthermore, protein MarT, positively regulates expression of misL by binding to misL-promoter. On the other hand, in SPI-3 of STY, marT and misL are pseudogenes. Interestingly, the gene t3766 (gene involved in resistance to H2O2) is present only in STY and is negatively regulated when marT STM is heterologously expressed in STY. Based on the view that MarT might regulate genes implicated in virulence, this work searched for new genes regulated by MarT. In silico searches for possible MarT target genes were performed, and 4 genes were selected for further analysis as they contained at least 2 copies of the consensus MarT-binding sequence in their promoters. Mutating marT in STM or heterologously expressing marT STM in STY confirmed that MarT negatively regulates ORF STY1408 or STM14_2003, its homologue in STM. STY1408 encodes for a putative protein with homology to methyl accepting chemotaxis proteins, which participate in chemotaxis and motility. Therefore, STY1408 was named mrmI (MarT-regulated motility gene I). Motility assays confirmed that the product of mrmI modulates motility. In addition, in vitro infection of cells with STM and STY mutants in mrmI reduces association with cells at 1, 3 and 24 h post-infection. Oral infection of mice showed that a mrmI null mutant was defective in producing systemic disease. Therefore, we conclude that MarT regulated mrmI, is involved in virulence of Salmonella. While pseudogenization of marT might modulate the fitness of narrow host range STY.
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Affiliation(s)
- Sebastián A. Jerez
- Programa de Doctorado en Biociencias Moleculares, Universidad Andres Bello, Santiago, Chile
| | - Aracely Y. Mora
- Advanced Center for Chronic Diseases, Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Ana R. Millanao
- Instituto de Farmacia, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Claudia P. Saavedra
- Laboratorio de Microbiología Molecular, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Sergio A. Bucarey
- Departamento de Ciencias Biológicas Animales, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago, Chile
| | - Guido C. Mora
- Instituto de Investigación Interdisciplinar en Ciencias Biomédicas SEK (I3CBSEK), Facultad de Ciencias de la Salud, Universidad SEK, Santiago, Chile
| | - Nicolás A. Villagra
- Escuela de Tecnología Médica, Facultad de Salud, Universidad Santo Tomas, Santiago, Chile
| | - Alejandro A. Hidalgo
- Laboratorio de Microbiología Molecular, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Escuela de Química y Farmacia, Facultad de Medicina, Universidad Andres Bello, Santiago, Chile
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2
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Xu W, Cerna-Vargas JP, Tajuelo A, Lozano-Montoya A, Kivoloka M, Krink N, Monteagudo-Cascales E, Matilla MA, Krell T, Sourjik V. Systematic mapping of chemoreceptor specificities for Pseudomonas aeruginosa. mBio 2023; 14:e0209923. [PMID: 37791891 PMCID: PMC10653921 DOI: 10.1128/mbio.02099-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 08/16/2023] [Indexed: 10/05/2023] Open
Abstract
IMPORTANCE Chemotaxis of motile bacteria has multiple physiological functions. It enables bacteria to locate optimal ecological niches, mediates collective behaviors, and can play an important role in infection. These multiple functions largely depend on ligand specificities of chemoreceptors, and the number and identities of chemoreceptors show high diversity between organisms. Similar diversity is observed for the spectra of chemoeffectors, which include not only chemicals of high metabolic value but also bacterial, plant, and animal signaling molecules. However, the systematic identification of chemoeffectors and their mapping to specific chemoreceptors remains a challenge. Here, we combined several in vivo and in vitro approaches to establish a systematic screening strategy for the identification of receptor ligands and we applied it to identify a number of new physiologically relevant chemoeffectors for the important opportunistic human pathogen P. aeruginosa. This strategy can be equally applicable to map specificities of sensory domains from a wide variety of receptor types and bacteria.
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Affiliation(s)
- Wenhao Xu
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Jean Paul Cerna-Vargas
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
- Centro de Biotecnología y Genómica de Plantas CBGP, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM, Pozuelo de Alarcón, Madrid, Spain
| | - Ana Tajuelo
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Andrea Lozano-Montoya
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Melissa Kivoloka
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Nicolas Krink
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Elizabet Monteagudo-Cascales
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Miguel A. Matilla
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Tino Krell
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Victor Sourjik
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
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3
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Phage Display-Derived Peptides and Antibodies for Bacterial Infectious Diseases Therapy and Diagnosis. Molecules 2023; 28:molecules28062621. [PMID: 36985593 PMCID: PMC10052323 DOI: 10.3390/molecules28062621] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/01/2023] [Accepted: 03/06/2023] [Indexed: 03/17/2023] Open
Abstract
The emergence of antibiotic-resistant-bacteria is a serious public health threat, which prompts us to speed up the discovery of novel antibacterial agents. Phage display technology has great potential to screen peptides or antibodies with high binding capacities for a wide range of targets. This property is significant in the rapid search for new antibacterial agents for the control of bacterial resistance. In this paper, we not only summarized the recent progress of phage display for the discovery of novel therapeutic agents, identification of action sites of bacterial target proteins, and rapid detection of different pathogens, but also discussed several problems of this technology that must be solved. Breakthrough in these problems may further promote the development and application of phage display technology in the biomedical field in the future.
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4
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Tetz V, Tetz G. Novel prokaryotic system employing previously unknown nucleic acids-based receptors. Microb Cell Fact 2022; 21:202. [PMID: 36195904 PMCID: PMC9531389 DOI: 10.1186/s12934-022-01923-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 09/16/2022] [Indexed: 12/26/2022] Open
Abstract
The present study describes a previously unknown universal system that orchestrates the interaction of bacteria with the environment, named the Teazeled receptor system (TR-system). The identical system was recently discovered within eukaryotes. The system includes DNA- and RNA-based molecules named "TezRs", that form receptor's network located outside the membrane, as well as reverse transcriptases and integrases. TR-system takes part in the control of all major aspects of bacterial behavior, such as intra cellular communication, growth, biofilm formation and dispersal, utilization of nutrients including xenobiotics, virulence, chemo- and magnetoreception, response to external factors (e.g., temperature, UV, light and gas content), mutation events, phage-host interaction, and DNA recombination activity. Additionally, it supervises the function of other receptor-mediated signaling pathways. Importantly, the TR-system is responsible for the formation and maintenance of cell memory to preceding cellular events, as well the ability to "forget" preceding events. Transcriptome and biochemical analysis revealed that the loss of different TezRs instigates significant alterations in gene expression and proteins synthesis.
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Affiliation(s)
- Victor Tetz
- Human Microbiology Institute, New York, NY, 10013, USA
| | - George Tetz
- Human Microbiology Institute, New York, NY, 10013, USA.
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5
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Shimizu K, Matsuoka Y. Feedback regulation and coordination of the main metabolism for bacterial growth and metabolic engineering for amino acid fermentation. Biotechnol Adv 2021; 55:107887. [PMID: 34921951 DOI: 10.1016/j.biotechadv.2021.107887] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 12/05/2021] [Accepted: 12/09/2021] [Indexed: 12/28/2022]
Abstract
Living organisms such as bacteria are often exposed to continuous changes in the nutrient availability in nature. Therefore, bacteria must constantly monitor the environmental condition, and adjust the metabolism quickly adapting to the change in the growth condition. For this, bacteria must orchestrate (coordinate and integrate) the complex and dynamically changing information on the environmental condition. In particular, the central carbon metabolism (CCM), monomer synthesis, and macromolecular synthesis must be coordinately regulated for the efficient growth. It is a grand challenge in bioscience, biotechnology, and synthetic biology to understand how living organisms coordinate the metabolic regulation systems. Here, we consider the integrated sensing of carbon sources by the phosphotransferase system (PTS), and the feed-forward/feedback regulation systems incorporated in the CCM in relation to the pool sizes of flux-sensing metabolites and αketoacids. We also consider the metabolic regulation of amino acid biosynthesis (as well as purine and pyrimidine biosyntheses) paying attention to the feedback control systems consisting of (fast) enzyme level regulation with (slow) transcriptional regulation. The metabolic engineering for the efficient amino acid production by bacteria such as Escherichia coli and Corynebacterium glutamicum is also discussed (in relation to the regulation mechanisms). The amino acid synthesis is important for determining the rate of ribosome biosynthesis. Thus, the growth rate control (growth law) is further discussed on the relationship between (p)ppGpp level and the ribosomal protein synthesis.
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Affiliation(s)
- Kazuyuki Shimizu
- Kyushu institute of Technology, Iizuka, Fukuoka 820-8502, Japan; Institute of Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0017, Japan.
| | - Yu Matsuoka
- Department of Fisheries Distribution and Management, National Fisheries University, Shimonoseki, Yamaguchi 759-6595, Japan
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6
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Gravina F, Degaut FL, Gerhardt ECM, Pedrosa FO, Souza EM, Antônio de Souza G, Huergo LF. The protein-protein interaction network of the Escherichia coli EIIA Ntr regulatory protein reveals a role in cell motility and metabolic control. Res Microbiol 2021; 172:103882. [PMID: 34563668 DOI: 10.1016/j.resmic.2021.103882] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 01/17/2023]
Abstract
The nitrogen-related PTSNtr system, present in many Proteobacteria including Escherichia coli, acts as a phosphorelay cascade composed of the EINtr, NPr and EIIANtr proteins. Phosphotransfer initiates with phosphoenolpyruvate-dependent EINtr autophosphorylation, the phosphoryl group is then transferred to NPr and finally to a conserved histidine residue on EIIANtr. The reporter metabolites L-glutamine and 2-oxoglutarate reciprocally regulate EINtr autophosphorylation (Lee et al. 2013) and consequently the phosphorylation status of the PTSNtr components is controlled by the availability of nitrogen and carbon. The final phosphate acceptor, EIIANtr, regulates a range of cellular process by acting as the central hub of a complex protein-protein interaction network. Contact between EIIANtr and its target proteins is usually regulated by the EIIANtr phosphorylation status. In this study we performed ligand fishing assays coupled to label-free quantitative proteomics to examine the protein-protein interaction network of E. coli EIIANtr and a phosphomimic variant of the protein. The ligand fishing data, along with phenotypic analysis, indicated that EIIANtr interacts with proteins related to chemotaxis and thereby regulates cell motility. Important metabolic enzymes were also identified as potential EIIANtr binding partners.
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Affiliation(s)
- Fernanda Gravina
- Departamento de Bioquímica e Biologia Molecular, UFPR Curitiba, PR, Brazil
| | - Flávia L Degaut
- Departamento de Bioquímica e Biologia Molecular, UFPR Curitiba, PR, Brazil
| | | | - Fabio O Pedrosa
- Departamento de Bioquímica e Biologia Molecular, UFPR Curitiba, PR, Brazil
| | - Emanuel M Souza
- Departamento de Bioquímica e Biologia Molecular, UFPR Curitiba, PR, Brazil
| | | | - Luciano F Huergo
- Departamento de Bioquímica e Biologia Molecular, UFPR Curitiba, PR, Brazil; Setor Litoral, UFPR Matinhos, PR, Brazil.
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The Azospirillum brasilense Core Chemotaxis Proteins CheA1 and CheA4 Link Chemotaxis Signaling with Nitrogen Metabolism. mSystems 2021; 6:6/1/e01354-20. [PMID: 33594007 PMCID: PMC8561660 DOI: 10.1128/msystems.01354-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Bacterial chemotaxis affords motile bacteria the ability to navigate the environment to locate niches for growth and survival. At the molecular level, chemotaxis depends on chemoreceptor signaling arrays that interact with cytoplasmic proteins to control the direction of movement. In Azospirillum brasilense, chemotaxis is mediated by two distinct chemotaxis pathways: Che1 and Che4. Both Che1 and Che4 are critical in the A. brasilense free-living and plant-associated lifestyles. Here, we use whole-cell proteomics and metabolomics to characterize the role of chemotaxis in A. brasilense physiology. We found that mutants lacking CheA1 or CheA4 or both are affected in nonchemotaxis functions, including major changes in transcription, signaling transport, and cell metabolism. We identify specific effects of CheA1 and CheA4 on nitrogen metabolism, including nitrate assimilation and nitrogen fixation, that may depend, at least, on the transcriptional control of rpoN, which encodes RpoN, a global regulator of metabolism, including nitrogen. Consistent with proteomics, the abundance of several nitrogenous compounds (purines, pyrimidines, and amino acids) changed in the metabolomes of the chemotaxis mutants relative to the parental strain. Further, we uncover novel, and yet uncharacterized, layers of transcriptional and posttranscriptional control of nitrogen metabolism regulators. Together, our data reveal roles for CheA1 and CheA4 in linking chemotaxis and nitrogen metabolism, likely through control of global regulatory networks. IMPORTANCE Bacterial chemotaxis is widespread in bacteria, increasing competitiveness in diverse environments and mediating associations with eukaryotic hosts ranging from commensal to beneficial and pathogenic. In most bacteria, chemotaxis signaling is tightly linked to energy metabolism, with this coupling occurring through the sensory input of several energy-sensing chemoreceptors. Here, we show that in A. brasilense the chemotaxis proteins have key roles in modulating nitrogen metabolism, including nitrate assimilation and nitrogen fixation, through novel and yet unknown regulations. These results are significant given that A. brasilense is a model bacterium for plant growth promotion and free-living nitrogen fixation and is used as a bio-inoculant for cereal crops. Chemotaxis signaling in A. brasilense thus links locomotor behaviors to nitrogen metabolism, allowing cells to continuously and reciprocally adjust metabolism and chemotaxis signaling as they navigate gradients.
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8
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Nitschke MR, Fidalgo C, Simões J, Brandão C, Alves A, Serôdio J, Frommlet JC. Symbiolite formation: a powerful in vitro model to untangle the role of bacterial communities in the photosynthesis-induced formation of microbialites. THE ISME JOURNAL 2020; 14:1533-1546. [PMID: 32203119 PMCID: PMC7242451 DOI: 10.1038/s41396-020-0629-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 02/21/2020] [Accepted: 02/28/2020] [Indexed: 11/09/2022]
Abstract
Microbially induced calcification is an ancient, community-driven mineralisation process that produces different types of microbialites. Symbiolites are photosynthesis-induced microbialites, formed by calcifying co-cultures of dinoflagellates from the family Symbiodiniaceae and bacteria. Symbiolites encase the calcifying community as endolithic cells, pointing at an autoendolithic niche of symbiotic dinoflagellates, and provide a rare opportunity to study the role of bacteria in bacterial-algal calcification, as symbiodiniacean cultures display either distinct symbiolite-producing (SP) or non-symbiolite-producing (NP) phenotypes. Using Illumina sequencing, we found that the bacterial communities of SP and NP cultures differed significantly in the relative abundance of 23 genera, 14 families, and 2 phyla. SP cultures were rich in biofilm digesters from the phylum Planctomycetes and their predicted metagenomes were enriched in orthologs related to biofilm formation. In contrast, NP cultures were dominated by biofilm digesters from the Bacteroidetes, and were inferred as enriched in proteases and nucleases. Functional assays confirmed the potential of co-cultures and bacterial isolates to produce biofilms and point at acidic polysaccharides as key stimulators for mineral precipitation. Hence, bacteria appear to influence symbiolite formation primarily through their biofilm-producing and modifying activity and we anticipate that symbiolite formation, as a low-complexity in vitro model, will significantly advance our understanding of photosynthesis-induced microbial calcification processes.
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Affiliation(s)
- Matthew R Nitschke
- Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal
- Climate Change Cluster, University of Technology Sydney, Broadway, NSW, 2007, Australia
| | - Cátia Fidalgo
- Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal
| | - João Simões
- Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Cláudio Brandão
- Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Artur Alves
- Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal
| | - João Serôdio
- Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Jörg C Frommlet
- Centre for Environmental and Marine Studies (CESAM), Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal.
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9
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Transporters of glucose and other carbohydrates in bacteria. Pflugers Arch 2020; 472:1129-1153. [PMID: 32372286 DOI: 10.1007/s00424-020-02379-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 12/18/2022]
Abstract
Glucose arguably is the most important energy carrier, carbon source for metabolites and building block for biopolymers in all kingdoms of life. The proper function of animal organs and tissues depends on the continuous supply of glucose from the bloodstream. Most animals can resorb only a small number of monosaccharides, mostly glucose, galactose and fructose, while all other sugars oligosaccharides and dietary fibers are degraded and metabolized by the microbiota of the lower intestine. Bacteria, in contrast, are omnivorous. They can import and metabolize structurally different sugars and, as a consortium of different species, utilize almost any sugar, sugar derivative and oligosaccharide occurring in nature. Bacteria have membrane transport systems for the uptake of sugars against steep concentration gradients energized by ATP, the proton motive force and the high energy glycolytic intermediate phosphoenolpyruvate (PEP). Different uptake mechanisms and the broad range of overlapping substrate specificities allow bacteria to quickly adapt to and colonize changing environments. Here, we review the structures and mechanisms of bacterial representatives of (i) ATP-dependent cassette (ABC) transporters, (ii) major facilitator (MFS) superfamily proton symporters, (iii) sodium solute symporters (SSS) and (iv) enzyme II integral membrane subunits of the bacterial PEP-dependent phosphotransferase system (PTS). We give a short overview on the distribution of transporter genes and their phylogenetic relationship in different bacterial species. Some sugar transporters are hijacked for import of bacteriophage DNA and antibacterial toxins (bacteriocins) and they facilitate the penetration of polar antibiotics. Finally, we describe how the expression and activity of certain sugar transporters are controlled in response to the availability of sugars and how the presence and uptake of sugars may affect pathogenicity and host-microbiota interactions.
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10
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Chung IY, Kim BO, Jang HJ, Cho YH. Repositioning of a mucolytic drug to a selective antibacterial against Vibrio cholerae. J Microbiol 2020; 58:61-66. [DOI: 10.1007/s12275-020-9590-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 12/12/2019] [Accepted: 12/13/2019] [Indexed: 12/19/2022]
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11
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Aboulwafa M, Zhang Z, Saier MH. Protein:Protein interactions in the cytoplasmic membrane apparently influencing sugar transport and phosphorylation activities of the e. coli phosphotransferase system. PLoS One 2019; 14:e0219332. [PMID: 31751341 PMCID: PMC6872149 DOI: 10.1371/journal.pone.0219332] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 10/13/2019] [Indexed: 01/05/2023] Open
Abstract
The multicomponent phosphoenolpyruvate (PEP)-dependent sugar-transporting phosphotransferase system (PTS) in Escherichia coli takes up sugar substrates from the medium and concomitantly phosphorylates them, releasing sugar phosphates into the cytoplasm. We have recently provided evidence that many of the integral membrane PTS permeases interact with the fructose PTS (FruA/FruB) [1]. However, the biochemical and physiological significance of this finding was not known. We have carried out molecular genetic/biochemical/physiological studies that show that interactions of the fructose PTS often enhance, but sometimes inhibit the activities of other PTS transporters many fold, depending on the target PTS system under study. Thus, the glucose (Glc), mannose (Man), mannitol (Mtl) and N-acetylglucosamine (NAG) permeases exhibit enhanced in vivo sugar transport and sometimes in vitro PEP-dependent sugar phosphorylation activities while the galactitol (Gat) and trehalose (Tre) systems show inhibited activities. This is observed when the fructose system is induced to high levels and prevented when the fruA/fruB genes are deleted. Overexpression of the fruA and/or fruB genes in the absence of fructose induction during growth also enhances the rates of uptake of other hexoses. The β-galactosidase activities of man, mtl, and gat-lacZ transcriptional fusions and the sugar-specific transphosphorylation activities of these enzyme transporters were not affected either by frustose induction or by fruAB overexpression, showing that the rates of synthesis of the target PTS permeases were not altered. We thus suggest that specific protein-protein interactions within the cytoplasmic membrane regulate transport in vivo (and sometimes the PEP-dependent phosphorylation activities in vitro) of PTS permeases in a physiologically meaningful way that may help to provide a hierarchy of preferred PTS sugars. These observations appear to be applicable in principle to other types of transport systems as well.
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Affiliation(s)
- Mohammad Aboulwafa
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA, United States of America
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University, Abbassia, Cairo, Egypt
| | - Zhongge Zhang
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA, United States of America
| | - Milton H. Saier
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA, United States of America
- * E-mail:
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12
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Strickland M, Kale S, Strub MP, Schwieters CD, Liu J, Peterkofsky A, Tjandra N. Potential Regulatory Role of Competitive Encounter Complexes in Paralogous Phosphotransferase Systems. J Mol Biol 2019; 431:2331-2342. [PMID: 31071328 DOI: 10.1016/j.jmb.2019.04.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/22/2019] [Accepted: 04/28/2019] [Indexed: 11/28/2022]
Abstract
There are two paralogous Escherichia coli phosphotransferase systems, one for sugar import (PTSsugar) and one for nitrogen regulation (PTSNtr), that utilize proteins enzyme Isugar (EIsugar) and HPr, and enzyme INtr (EINtr) and NPr, respectively. The enzyme I proteins have similar folds, as do their substrates HPr and NPr, yet they show strict specificity for their cognate partner both in stereospecific protein-protein complex formation and in reversible phosphotransfer. Here, we investigate the mechanism of specific EINtr:NPr complex formation by the study of transient encounter complexes. NMR paramagnetic relaxation enhancement experiments demonstrated transient encounter complexes of EINtr not only with the expected partner, NPr, but also with the unexpected partner, HPr. HPr occupies transient sites on EINtr but is unable to complete stereospecific complex formation. By occupying the non-productive transient sites, HPr promotes NPr transient interaction to productive sites closer to the stereospecific binding site and actually enhances specific complex formation between NPr and EINtr. The cellular level of HPr is approximately 150 times higher than that of NPr. Thus, our finding suggests a potential mechanism for cross-regulation of enzyme activity through formation of competitive encounter complexes.
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Affiliation(s)
- Madeleine Strickland
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Seyit Kale
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Marie-Paule Strub
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Charles D Schwieters
- Office of Intramural Research, Center for Information Technology, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jian Liu
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Alan Peterkofsky
- Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Nico Tjandra
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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13
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Martins GB, Giacomelli G, Goldbeck O, Seibold GM, Bramkamp M. Substrate-dependent cluster density dynamics of Corynebacterium glutamicum phosphotransferase system permeases. Mol Microbiol 2019; 111:1335-1354. [PMID: 30748039 PMCID: PMC6850760 DOI: 10.1111/mmi.14224] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2019] [Indexed: 11/29/2022]
Abstract
Many bacteria take up carbohydrates by membrane‐integral sugar specific phosphoenolpyruvate‐dependent carbohydrate:phosphotransferase systems (PTS). Although the PTS is centrally involved in regulation of carbon metabolism in different bacteria, little is known about localization and putative oligomerization of the permease subunits (EII). Here, we analyzed localization of the fructose specific PtsF and the glucose specific PtsG transporters, as well as the general components EI and HPr from Corynebacterium glutamicum using widefield and single molecule localization microscopy. PtsF and PtsG form membrane embedded clusters that localize in a punctate pattern. Size, number and fluorescence of the membrane clusters change upon presence or absence of the transported substrate, and a direct influence of EI and HPr was not observed. In presence of the transport substrate, EII clusters significantly increased in size. Photo‐activated localization microscopy data revealed that, in presence of different carbon sources, the number of EII proteins per cluster remains the same, however, the density of these clusters reduces. Our work reveals a simple mechanism for efficient membrane occupancy regulation. Clusters of PTS EII transporters are densely packed in absence of a suitable substrate. In presence of a transported substrate, the EII proteins in individual clusters occupy larger membrane areas.
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Affiliation(s)
- Gustavo Benevides Martins
- Faculty of Biology, Ludwig-Maximilians-Universität München, Großhaderner Straße 2-4, Planegg-Martinsried, 82152, Germany
| | - Giacomo Giacomelli
- Faculty of Biology, Ludwig-Maximilians-Universität München, Großhaderner Straße 2-4, Planegg-Martinsried, 82152, Germany
| | - Oliver Goldbeck
- Institute of Microbiology and Biotechnology, Ulm University, Albert-Einstein Allee 11, Ulm, 89081, Germany
| | - Gerd M Seibold
- Institute of Microbiology and Biotechnology, Ulm University, Albert-Einstein Allee 11, Ulm, 89081, Germany
| | - Marc Bramkamp
- Faculty of Biology, Ludwig-Maximilians-Universität München, Großhaderner Straße 2-4, Planegg-Martinsried, 82152, Germany
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14
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Jeckelmann JM, Erni B. Carbohydrate Transport by Group Translocation: The Bacterial Phosphoenolpyruvate: Sugar Phosphotransferase System. Subcell Biochem 2019; 92:223-274. [PMID: 31214989 DOI: 10.1007/978-3-030-18768-2_8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The Bacterial Phosphoenolpyruvate (PEP) : Sugar Phosphotransferase System (PTS) mediates the uptake and phosphorylation of carbohydrates, and controls the carbon- and nitrogen metabolism in response to the availability of sugars. PTS occur in eubacteria and in a few archaebacteria but not in animals and plants. All PTS comprise two cytoplasmic phosphotransferase proteins (EI and HPr) and a species-dependent, variable number of sugar-specific enzyme II complexes (IIA, IIB, IIC, IID). EI and HPr transfer phosphorylgroups from PEP to the IIA units. Cytoplasmic IIA and IIB units sequentially transfer phosphates to the sugar, which is transported by the IIC and IICIID integral membrane protein complexes. Phosphorylation by IIB and translocation by IIC(IID) are tightly coupled. The IIC(IID) sugar transporters of the PTS are in the focus of this review. There are four structurally different PTS transporter superfamilies (glucose, glucitol, ascorbate, mannose) . Crystal structures are available for transporters of two superfamilies: bcIICmal (MalT, 5IWS, 6BVG) and bcIICchb (ChbC, 3QNQ) of B. subtilis from the glucose family, and IICasc (UlaA, 4RP9, 5ZOV) of E. coli from the ascorbate superfamily . They are homodimers and each protomer has an independent transport pathway which functions by an elevator-type alternating-access mechanism. bcIICmal and bcIICchb have the same fold, IICasc has a completely different fold. Biochemical and biophysical data accumulated in the past with the transporters for mannitol (IICBAmtl) and glucose (IICBglc) are reviewed and discussed in the context of the bcIICmal crystal structures. The transporters of the mannose superfamily are dimers of protomers consisting of a IIC and a IID protein chain. The crystal structure is not known and the topology difficult to predict. Biochemical data indicate that the IICIID complex employs a different transport mechanism . Species specific IICIID serve as a gateway for the penetration of bacteriophage lambda DNA across, and insertion of class IIa bacteriocins into the inner membrane. PTS transporters are inserted into the membrane by SecYEG translocon and have specific lipid requirements. Immunoelectron- and fluorescence microscopy indicate a non-random distribution and supramolecular complexes of PTS proteins.
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Affiliation(s)
- Jean-Marc Jeckelmann
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012, Bern, Switzerland.
| | - Bernhard Erni
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012, Bern, Switzerland
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15
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Kalily E, Hollander A, Korin B, Cymerman I, Yaron S. Adaptation of Salmonella enterica Serovar Senftenberg to Linalool and Its Association with Antibiotic Resistance and Environmental Persistence. Appl Environ Microbiol 2017; 83:e03398-16. [PMID: 28258149 PMCID: PMC5411494 DOI: 10.1128/aem.03398-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 02/22/2017] [Indexed: 11/20/2022] Open
Abstract
A clinical isolate of Salmonella enterica serovar Senftenberg, isolated from an outbreak linked to the herb Ocimum basilicum L. (basil), has been shown to be resistant to basil oil and to the terpene alcohol linalool. To better understand how human pathogens might develop resistance to linalool and to investigate the association of this resistance with resistance to different antimicrobial agents, selective pressure was applied to the wild-type strain by sequential exposure to increasing concentrations of linalool. The results demonstrated that S Senftenberg adapted to linalool with a MIC increment of at least 8-fold, which also resulted in better resistance to basil oil and better survival on harvested basil leaves. Adaptation to linalool was shown to confer cross protection against the antibiotics trimethoprim, sulfamethoxazole, piperacillin, chloramphenicol, and tetracycline, increasing their MICs by 2- to 32-fold. The improved resistance was shown to correlate with multiple phenotypes that included changes in membrane fatty acid composition, induced efflux, reduced influx, controlled motility, and the ability to form larger aggregates in the presence of linalool. The adaptation to linalool obtained in vitro did not affect survival on the basil phyllosphere in planta and even diminished survival in soil, suggesting that development of extreme resistance to linalool may be accompanied by a loss of fitness. Altogether, this report notes the concern regarding the ability of human pathogens to develop resistance to commercial essential oils, a resistance that is also associated with cross-resistance to antibiotics and may endanger public health.IMPORTANCE Greater consumer awareness and concern regarding synthetic chemical additives have led producers to control microbial spoilage and hazards by the use of natural preservatives, such as plant essential oils with antimicrobial activity. This report establishes, however, that these compounds may provoke the emergence of resistant human pathogens. Herein, we demonstrate the acquisition of resistance to basil oil by Salmonella Senftenberg. Exposure to linalool, a component of basil oil, resulted in adaptation to the basil oil mixture, as well as cross protection against several antibiotics and better survival on harvested basil leaves. Collectively, this work highlights the hazard to public health while using plant essential oils without sufficient knowledge about their influence on pathogens at subinhibitory concentrations.
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Affiliation(s)
- Emmanuel Kalily
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
| | - Amit Hollander
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
| | - Ben Korin
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
| | - Itamar Cymerman
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
| | - Sima Yaron
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
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16
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Endozoicomonas genomes reveal functional adaptation and plasticity in bacterial strains symbiotically associated with diverse marine hosts. Sci Rep 2017; 7:40579. [PMID: 28094347 PMCID: PMC5240137 DOI: 10.1038/srep40579] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 12/07/2016] [Indexed: 01/22/2023] Open
Abstract
Endozoicomonas bacteria are globally distributed and often abundantly associated with diverse marine hosts including reef-building corals, yet their function remains unknown. In this study we generated novel Endozoicomonas genomes from single cells and metagenomes obtained directly from the corals Stylophora pistillata, Pocillopora verrucosa, and Acropora humilis. We then compared these culture-independent genomes to existing genomes of bacterial isolates acquired from a sponge, sea slug, and coral to examine the functional landscape of this enigmatic genus. Sequencing and analysis of single cells and metagenomes resulted in four novel genomes with 60–76% and 81–90% genome completeness, respectively. These data also confirmed that Endozoicomonas genomes are large and are not streamlined for an obligate endosymbiotic lifestyle, implying that they have free-living stages. All genomes show an enrichment of genes associated with carbon sugar transport and utilization and protein secretion, potentially indicating that Endozoicomonas contribute to the cycling of carbohydrates and the provision of proteins to their respective hosts. Importantly, besides these commonalities, the genomes showed evidence for differential functional specificity and diversification, including genes for the production of amino acids. Given this metabolic diversity of Endozoicomonas we propose that different genotypes play disparate roles and have diversified in concert with their hosts.
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17
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Strickland M, Stanley AM, Wang G, Botos I, Schwieters CD, Buchanan SK, Peterkofsky A, Tjandra N. Structure of the NPr:EIN Ntr Complex: Mechanism for Specificity in Paralogous Phosphotransferase Systems. Structure 2016; 24:2127-2137. [PMID: 27839951 PMCID: PMC5143221 DOI: 10.1016/j.str.2016.10.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Revised: 10/03/2016] [Accepted: 10/12/2016] [Indexed: 12/13/2022]
Abstract
Paralogous enzymes arise from gene duplication events that confer a novel function, although it is unclear how cross-reaction between the original and duplicate protein interaction network is minimized. We investigated HPr:EIsugar and NPr:EINtr, the initial complexes of paralogous phosphorylation cascades involved in sugar import and nitrogen regulation in bacteria, respectively. Although the HPr:EIsugar interaction has been well characterized, involving multiple complexes and transient interactions, the exact nature of the NPr:EINtr complex was unknown. We set out to identify the key features of the interaction by performing binding assays and elucidating the structure of NPr in complex with the phosphorylation domain of EINtr (EINNtr), using a hybrid approach involving X-ray, homology, and sparse nuclear magnetic resonance. We found that the overall fold and active-site structure of the two complexes are conserved in order to maintain productive phosphorylation, however, the interface surface potential differs between the two complexes, which prevents cross-reaction.
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Affiliation(s)
- Madeleine Strickland
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ann Marie Stanley
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Guangshun Wang
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Istvan Botos
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Charles D Schwieters
- Office of Intramural Research, Center for Information Technology, National Institutes of Health, Bethesda, MD 20892, USA
| | - Susan K Buchanan
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Alan Peterkofsky
- Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Nico Tjandra
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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18
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Somavanshi R, Ghosh B, Sourjik V. Sugar Influx Sensing by the Phosphotransferase System of Escherichia coli. PLoS Biol 2016; 14:e2000074. [PMID: 27557415 PMCID: PMC4996493 DOI: 10.1371/journal.pbio.2000074] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 07/20/2016] [Indexed: 12/05/2022] Open
Abstract
The phosphotransferase system (PTS) plays a pivotal role in the uptake of multiple sugars in Escherichia coli and many other bacteria. In the cell, individual sugar-specific PTS branches are interconnected through a series of phosphotransfer reactions, thus creating a global network that not only phosphorylates incoming sugars but also regulates a number of cellular processes. Despite the apparent importance of the PTS network in bacterial physiology, the holistic function of the network in the cell remains unclear. Here we used Förster resonance energy transfer (FRET) to investigate the PTS network in E. coli, including the dynamics of protein interactions and the processing of different stimuli and their transmission to the chemotaxis pathway. Our results demonstrate that despite the seeming complexity of the cellular PTS network, its core part operates in a strikingly simple way, sensing the overall influx of PTS sugars irrespective of the sugar identity and distributing this information equally through all studied branches of the network. Moreover, it also integrates several other specific metabolic inputs. The integrated output of the PTS network is then transmitted linearly to the chemotaxis pathway, in stark contrast to the amplification of conventional chemotactic stimuli. Finally, we observe that default uptake through the uninduced PTS network correlates well with the quality of the carbon source, apparently representing an optimal regulatory strategy. The bacterial phosphotransferase system (PTS) mediates uptake of multiple sugars from the environment and also controls cell physiology and swimming behavior in sugar gradients. In Escherichia coli and other bacteria, the PTS consists of a number of sugar-specific branches, interconnected via shared components through a series of phosphotransfer reactions. Whereas most previous studies have focused on understanding individual PTS branches, the holistic function of the entire PTS network in the cell remained elusive. In this study we address this question by investigating the dynamics of multiple protein interactions within the cellular PTS network upon stimulation with sugars and other metabolites. We demonstrate that despite its seeming complexity, the core part of the PTS network operates in a strikingly simple way, sensing the overall influx of PTS sugars and key metabolites into the cell and utilizing this information to control bacterial behavior. We further show that the default influx of the carbon source correlates with its quality, and we use computer simulations to demonstrate that this correlation apparently represents an optimal regulatory strategy.
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Affiliation(s)
- Rahul Somavanshi
- Max Planck Institute for Terrestrial Microbiology & LOEWE Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Bhaswar Ghosh
- Max Planck Institute for Terrestrial Microbiology & LOEWE Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Victor Sourjik
- Max Planck Institute for Terrestrial Microbiology & LOEWE Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
- * E-mail:
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19
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Where are things inside a bacterial cell? Curr Opin Microbiol 2016; 33:83-90. [PMID: 27450542 DOI: 10.1016/j.mib.2016.07.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 06/21/2016] [Accepted: 07/06/2016] [Indexed: 01/13/2023]
Abstract
Bacterial cells are intricately organized, despite the lack of membrane-bounded organelles. The extremely crowded cytoplasm promotes macromolecular self-assembly and formation of distinct subcellular structures, which perform specialized functions. For example, the cell poles act as hubs for signal transduction complexes, thus providing a platform for the coordination of optimal cellular responses to environmental cues. Distribution of macromolecules is mostly mediated via specialized transport machineries, including the MreB cytoskeleton. Recent evidence shows that RNAs also specifically localize within bacterial cells, raising the possibility that gene expression is spatially organized. Here we review the current understanding of where things are in bacterial cells and discuss emerging questions that need to be addressed in the future.
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20
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Leng Y, Vakulskas CA, Zere TR, Pickering BS, Watnick PI, Babitzke P, Romeo T. Regulation of CsrB/C sRNA decay by EIIA(Glc) of the phosphoenolpyruvate: carbohydrate phosphotransferase system. Mol Microbiol 2015; 99:627-39. [PMID: 26507976 DOI: 10.1111/mmi.13259] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2015] [Indexed: 02/06/2023]
Abstract
Csr is a conserved global regulatory system, which uses the sequence-specific RNA-binding protein CsrA to activate or repress gene expression by binding to mRNA and altering translation, stability and/or transcript elongation. In Escherichia coli, CsrA activity is regulated by two sRNAs, CsrB and CsrC, which bind to multiple CsrA dimers, thereby sequestering this protein away from its mRNA targets. Turnover of CsrB/C sRNAs is tightly regulated by a GGDEF-EAL domain protein, CsrD, which targets them for cleavage by RNase E. Here, we show that EIIA(Glc) of the glucose-specific PTS system is also required for the normal decay of these sRNAs and that it acts by binding to the EAL domain of CsrD. Only the unphosphorylated form of EIIA(Glc) bound to CsrD in vitro and was capable of activating CsrB/C turnover in vivo. Genetic studies confirmed that this mechanism couples CsrB/C sRNA decay to the availability of a preferred carbon source. These findings reveal a new physiological influence on the workings of the Csr system, a novel function for the EAL domain, and an important new way in which EIIA(Glc) shapes global regulatory circuitry in response to nutritional status.
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Affiliation(s)
- Yuanyuan Leng
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611-0700, USA
| | - Christopher A Vakulskas
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611-0700, USA
| | - Tesfalem R Zere
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611-0700, USA
| | - Bradley S Pickering
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Paula I Watnick
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Paul Babitzke
- Department of Biochemistry and Molecular Biology, Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Tony Romeo
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, 32611-0700, USA
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21
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Park YH, Um SH, Song S, Seok YJ, Ha NC. Structural basis for the sequestration of the anti-σ(70) factor Rsd from σ(70) by the histidine-containing phosphocarrier protein HPr. ACTA ACUST UNITED AC 2015; 71:1998-2008. [PMID: 26457424 DOI: 10.1107/s1399004715013759] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 07/20/2015] [Indexed: 11/10/2022]
Abstract
Histidine-containing phosphocarrier protein (HPr) is a general component of the bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) involved in the phosphorylation-coupled transport of numerous sugars called PTS sugars. HPr mainly exists in a dephosphorylated form in the presence of PTS sugars in the medium, while its phosphorylation increases in the absence of PTS sugars. A recent study revealed that the dephosphorylated form of HPr binds and antagonizes the function of the antisigma factor Rsd. This anti-sigma factor sequesters the housekeeping sigma factor σ(70) to facilitate switching of the sigma subunit on RNA polymerase from σ(70) to the stress-responsive sigma factor σ(S) in stationary-phase cells. In this study, the structure of the complex of Rsd and HPr was determined at 2.1 Å resolution and revealed that the binding site for HPr on the surface of Rsd partly overlaps with that for σ(70). The localization of the phosphorylation site on HPr at the binding interface for Rsd explains why phosphorylation of HPr abolishes its binding to Rsd. The mutation of crucial residues involved in the HPr-Rsd interaction significantly influenced the competition between HPr and σ(70) for binding to Rsd both in vitro and in vivo. The results provide a structural basis for the linkage of global gene regulation to nutrient availability in the external environment.
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Affiliation(s)
- Young Ha Park
- Department of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 151-742, Republic of Korea
| | - Si Hyeon Um
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Research Institute for Agricultural and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Saemee Song
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Research Institute for Agricultural and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
| | - Yeong Jae Seok
- Department of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 151-742, Republic of Korea
| | - Nam Chul Ha
- Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Research Institute for Agricultural and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
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22
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Uday Bhaskar RVS, Karmakar R, Deepika D, Tirumkudulu MS, Venkatesh KV. Variation of swimming speed enhances the chemotactic migration of Escherichia coli. SYSTEMS AND SYNTHETIC BIOLOGY 2015; 9:85-95. [PMID: 26279703 PMCID: PMC4531881 DOI: 10.1007/s11693-015-9174-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 06/22/2015] [Accepted: 07/01/2015] [Indexed: 01/09/2023]
Abstract
Studies on chemotaxis of Escherichia coli have shown that modulation of tumble frequency causes a net drift up the gradient of attractants. Recently, it has been demonstrated that the bacteria is also capable of varying its runs speed in uniform concentration of attractant. In this study, we investigate the role of swimming speed on the chemotactic migration of bacteria. To this end, cells are exposed to gradients of a non-metabolizable analogue of glucose which are sensed via the Trg sensor. When exposed to a gradient, the cells modulate their tumble duration, which is accompanied with variation in swimming speed leading to drift velocities that are much higher than those achieved through the modulation of the tumble duration alone. We use an existing intra-cellular model developed for the Tar receptor and incorporate the variation of the swimming speed along with modulation of tumble frequency to predict drift velocities close to the measured values. The main implication of our study is that E. coli not only modulates the tumble frequency, but may also vary the swimming speed to affect chemotaxis and thereby efficiently sample its nutritionally rich environment.
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Affiliation(s)
| | - Richa Karmakar
- Department of Chemical Engineering, IIT Bombay, Mumbai, 400076 India
| | - Deepti Deepika
- Department of Chemical Engineering, IIT Bombay, Mumbai, 400076 India
| | | | - K. V. Venkatesh
- Department of Chemical Engineering, IIT Bombay, Mumbai, 400076 India
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23
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Kuhlmann N, Petrov DP, Henrich AW, Lindner SN, Wendisch VF, Seibold GM. Transcription of malP is subject to phosphotransferase system-dependent regulation in Corynebacterium glutamicum. Microbiology (Reading) 2015; 161:1830-1843. [DOI: 10.1099/mic.0.000134] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Nora Kuhlmann
- Institute of Biochemistry, Department of Chemistry, University of Cologne, D-50674 Cologne, Germany
| | - Dimitar P. Petrov
- Institute of Biochemistry, Department of Chemistry, University of Cologne, D-50674 Cologne, Germany
| | - Alexander W. Henrich
- Institute of Biochemistry, Department of Chemistry, University of Cologne, D-50674 Cologne, Germany
| | - Steffen N. Lindner
- Faculty of Biology & CeBiTec, Bielefeld University, D-33501 Bielefeld, Germany
| | - Volker F. Wendisch
- Faculty of Biology & CeBiTec, Bielefeld University, D-33501 Bielefeld, Germany
| | - Gerd M. Seibold
- Institute of Biochemistry, Department of Chemistry, University of Cologne, D-50674 Cologne, Germany
- Institute of Microbiology and Biotechnology, Faculty of Natural Sciences, Ulm University, D-89081 Ulm, Germany
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24
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Liang Q, Zhang F, Li Y, Zhang X, Li J, Yang P, Qi Q. Comparison of individual component deletions in a glucose-specific phosphotransferase system revealed their different applications. Sci Rep 2015; 5:13200. [PMID: 26285685 PMCID: PMC4541071 DOI: 10.1038/srep13200] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 07/14/2015] [Indexed: 01/28/2023] Open
Abstract
The phosphoenolpyruvate-dependent glucose-specific phosphotransferase system (PTSGlc) is the main glucose uptake pathway in Escherichia coli that affects both substrate assimilation and metabolism leading to the product formation. In this study, the effect of single PTSGlc mutation on cell growth and substrate consumption was investigated by knocking out the genes involved in the phosphotransfer cascade of the PTSGlc. In addition, the distribution of the metabolites of mutants was analyzed. Each mutant was confirmed to have different adaptability in the presence of both glucose and xylose with different ratios, and a substrate mixture with high xylose content can be completely consumed in short time when the ptsI mutant is employed. Finally, ptsH deletion was for the first time applied for succinate production due to its well performance under anaerobic condition. Strain YL104H, in which ptsH was deleted, exhibited considerably increased succinate yield under both aerobic and anaerobic conditions. The succinate titer and overall productivity reached 511.11 mM and 1.01 g/L/h after 60 h during the whole-phase fermentation in a mineral salt medium. The present results demonstrated the glucose and xylose co-utilization efficiency and the product yield and productivity can be significantly improved if a suitable PTSGlc deletion mutant was selected.
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Affiliation(s)
- Quanfeng Liang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, P. R. China
| | - Fengyu Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, P. R. China
| | - Yikui Li
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, P. R. China
| | - Xu Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, P. R. China
| | - Jiaojiao Li
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, P. R. China
| | - Peng Yang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, P. R. China
| | - Qingsheng Qi
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, P. R. China
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25
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Lengeler JW. PTS 50: Past, Present and Future, or Diauxie Revisited. J Mol Microbiol Biotechnol 2015; 25:79-93. [DOI: 10.1159/000369809] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
<b><i>Past:</i></b> The title ‘PTS 50 or The PTS after 50 years' relies on the first description in 1964 of the phosphoenolpyruvate-dependent carbohydrate:phosphotransferase system (PTS) by Kundig, Gosh and Roseman [Proc Natl Acad Sci USA 1964;52:1067-1074]. The system comprised proteins named Enzyme I, HPr and Enzymes II, as part of a novel PTS for carbohydrates in Gram-negative and Gram-positive bacteria, whose ‘biological significance remained unclear'. In contrast, studies which would eventually lead to the discovery of the central role of the PTS in bacterial metabolism had been published since before 1942. They are primarily linked to names like Epps and Gale, J. Monod, Cohn and Horibata, and B. Magasanik, and to phenomena like ‘glucose effects', ‘diauxie', ‘catabolite repression' and carbohydrate transport. <b><i>Present:</i></b> The pioneering work from Roseman's group initiated a flood of publications. The extraordinary progress from 1964 to this day in the qualitative and in vitro description of the genes and enzymes of the PTS, and of its multiple roles in global cellular control through ‘inducer exclusion', gene induction and ‘catabolite repression', in cellular growth, in cell differentiation and in chemotaxis, as well as the differences of its functions between Gram-positive and Gram-negative bacteria, was one theme of the meeting and will not be treated in detail here. <b><i>Future:</i></b> At the 1988 Paris meeting entitled ‘The PTS after 25 years', Saul Roseman predicted that ‘we must describe these interactions [of the PTS components] in a quantitative way [under] in vivo conditions'. I will present some results obtained by our group during recent years on the old phenomenon of diauxie by means of very fast and quantitative tests, measured in vivo, and obtained from cultures of isogenic mutant strains growing under chemostat conditions. The results begin to hint at the problems relating to future PTS research, but also to the ‘true science' of Roseman.
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The bacterial phosphoenolpyruvate:carbohydrate phosphotransferase system: regulation by protein phosphorylation and phosphorylation-dependent protein-protein interactions. Microbiol Mol Biol Rev 2015; 78:231-56. [PMID: 24847021 DOI: 10.1128/mmbr.00001-14] [Citation(s) in RCA: 281] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The bacterial phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS) carries out both catalytic and regulatory functions. It catalyzes the transport and phosphorylation of a variety of sugars and sugar derivatives but also carries out numerous regulatory functions related to carbon, nitrogen, and phosphate metabolism, to chemotaxis, to potassium transport, and to the virulence of certain pathogens. For these different regulatory processes, the signal is provided by the phosphorylation state of the PTS components, which varies according to the availability of PTS substrates and the metabolic state of the cell. PEP acts as phosphoryl donor for enzyme I (EI), which, together with HPr and one of several EIIA and EIIB pairs, forms a phosphorylation cascade which allows phosphorylation of the cognate carbohydrate bound to the membrane-spanning EIIC. HPr of firmicutes and numerous proteobacteria is also phosphorylated in an ATP-dependent reaction catalyzed by the bifunctional HPr kinase/phosphorylase. PTS-mediated regulatory mechanisms are based either on direct phosphorylation of the target protein or on phosphorylation-dependent interactions. For regulation by PTS-mediated phosphorylation, the target proteins either acquired a PTS domain by fusing it to their N or C termini or integrated a specific, conserved PTS regulation domain (PRD) or, alternatively, developed their own specific sites for PTS-mediated phosphorylation. Protein-protein interactions can occur with either phosphorylated or unphosphorylated PTS components and can either stimulate or inhibit the function of the target proteins. This large variety of signal transduction mechanisms allows the PTS to regulate numerous proteins and to form a vast regulatory network responding to the phosphorylation state of various PTS components.
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Lee J, Park YH, Kim YR, Seok YJ, Lee CR. Dephosphorylated NPr is involved in an envelope stress response of Escherichia coli. MICROBIOLOGY-SGM 2015; 161:1113-1123. [PMID: 25701731 PMCID: PMC4635465 DOI: 10.1099/mic.0.000056] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 02/10/2015] [Indexed: 01/20/2023]
Abstract
Besides the canonical phosphoenolpyruvate-dependent phosphotransferase system (PTS) for carbohydrate transport, most Proteobacteria possess the so-called nitrogen PTS (PTSNtr) that transfers a phosphate group from phosphoenolpyruvate (PEP) over enzyme INtr (EINtr) and NPr to enzyme IIANtr (EIIANtr). The PTSNtr lacks membrane-bound components and functions exclusively in a regulatory capacity. While EIIANtr has been implicated in a variety of cellular processes such as potassium homeostasis, phosphate starvation, nitrogen metabolism, carbon metabolism, regulation of ABC transporters and poly-β-hydroxybutyrate accumulation in many Proteobacteria, the only identified role of NPr is the regulation of biosynthesis of the lipopolysaccharide (LPS) layer by direct interaction with LpxD in Escherichia coli. In this study, we provide another phenotype related to NPr. Several lines of evidence demonstrate that E. coli strains with increased levels of dephosphorylated NPr are sensitive to envelope stresses, such as osmotic, ethanol and SDS stresses, and these phenotypes are independent of LpxD. The C-terminal region of NPr plays an important role in sensitivity to envelope stresses. Thus, our data suggest that the dephospho-form of NPr affects adaptation to envelope stresses through a C-terminus-dependent mechanism.
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Affiliation(s)
- Jaeseop Lee
- Department of Biological Sciences, Myongji University, Yongin, Gyeonggido 449-728, Republic of Korea
| | - Young-Ha Park
- Department of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 151-742, Republic of Korea
| | - Yeon-Ran Kim
- Department of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 151-742, Republic of Korea
| | - Yeong-Jae Seok
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul 151-742, Republic of Korea.,Department of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 151-742, Republic of Korea
| | - Chang-Ro Lee
- Department of Biological Sciences, Myongji University, Yongin, Gyeonggido 449-728, Republic of Korea
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Kim HM, Park YH, Yoon CK, Seok YJ. Histidine phosphocarrier protein regulates pyruvate kinase A activity in response to glucose in Vibrio vulnificus. Mol Microbiol 2015; 96:293-305. [PMID: 25598011 DOI: 10.1111/mmi.12936] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2015] [Indexed: 11/29/2022]
Abstract
The bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) consists of two general energy-coupling proteins [enzyme I and histidine phosphocarrier protein (HPr)] and several sugar-specific enzyme IIs. Although, in addition to the phosphorylation-coupled transport of sugars, various regulatory roles of PTS components have been identified in Escherichia coli, much less is known about the PTS in the opportunistic human pathogen Vibrio vulnificus. In this study, we have identified pyruvate kinase A (PykA) as a binding partner of HPr in V. vulnificus. The interaction between HPr and PykA was strictly dependent on the presence of inorganic phosphate, and only dephosphorylated HPr interacted with PykA. Experiments involving domain swapping between the PykAs of V. vulnificus and E. coli revealed the requirement for the C-terminal domain of V. vulnificus PykA for a specific interaction with V. vulnificus HPr. Dephosphorylated HPr decreased the Km of PykA for phosphoenolpyruvate by approximately fourfold without affecting Vmax . Taken together, these findings indicate that the V. vulnificus PTS catalyzing the first step of glycolysis stimulates the final step of glycolysis in the presence of glucose through the direct interaction of dephospho-HPr with the C-terminal domain of PykA.
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Affiliation(s)
- Hey-Min Kim
- Department of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, 151-742, South Korea
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Amster-Choder O. The compartmentalized vessel: The bacterial cell as a model for subcellular organization (a tale of two studies). CELLULAR LOGISTICS 2014; 1:77-81. [PMID: 21686257 DOI: 10.4161/cl.1.2.16152] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 04/26/2011] [Accepted: 04/26/2011] [Indexed: 12/22/2022]
Abstract
The traditional view of bacterial cells as non-compartmentalized, which is based on the lack of membrane-engulfed organelles, is currently being reassessed. Many studies in recent years led to the realization that bacteria have an intricate internal organization that is vital for various cellular processes. Specifically, various machineries were shown to localize to the poles of rod-shaped bacteria. We have recently shown that the control center of the PTS system, which governs carbon uptake and metabolism, localizes to the poles of E. coli cells. Notably, the machinery that controls bacterial taxis along chemical gradients (chemotaxis) has a similar localization pattern. The fact that the two systems need to communicate in order to generate an optimal metabolic response suggests that their similar spatial organization is not a coincidence. Rather, due to their special characteristics, the poles may function as hubs for signaling systems to allow for efficient crosstalk between different pathways in order to improve coordination of their actions.The regulatory mechanisms that underlie the spatial and temporal organization of microbial cells are largely unknown. Thus far, these mechanisms were believed to rely on embedded features of the localized proteins. In another study, we have recently shown that mRNAs are capable of migrating to particular domains in the bacterial cell where their protein products are required. In contrast to the view that transcription and translation are coupled in bacteria, localization of bacterial transcripts may occur in a translation-independent manner. Hence, it seems that the mechanistic basis for separating transcription and translation is more primitive than assumed up until now. We propose that bacteria synthesize proteins either by a transcription-translation coupled mechanism or by transporting mRNAs away from the transcription apparatus. Obviously, eukaryotic cells rely on the latter mechanism. Hence, the capacity of prokaryotic cells to adopt the division between transcription and translation was a crucial step in the evolution of nucleus-containing cells from the prokaryotic origin. Summarily, the line that separates cells with nucleus and cells without is fading, leading to the realization that bacteria are suitable model organisms for studying universal mechanisms that underlie spatial regulation of cellular processes.
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Affiliation(s)
- Orna Amster-Choder
- Department of Microbiology and Molecular Genetics; IMRIC; Hadassah Medical School; The Hebrew University; Jerusalem, Israel
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Dintner S, Heermann R, Fang C, Jung K, Gebhard S. A sensory complex consisting of an ATP-binding cassette transporter and a two-component regulatory system controls bacitracin resistance in Bacillus subtilis. J Biol Chem 2014; 289:27899-910. [PMID: 25118291 DOI: 10.1074/jbc.m114.596221] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Resistance against antimicrobial peptides in many Firmicutes bacteria is mediated by detoxification systems that are composed of a two-component regulatory system (TCS) and an ATP-binding cassette (ABC) transporter. The histidine kinases of these systems depend entirely on the transporter for sensing of antimicrobial peptides, suggesting a novel mode of signal transduction where the transporter constitutes the actual sensor. The aim of this study was to investigate the molecular mechanisms of this unusual signaling pathway in more detail, using the bacitracin resistance system BceRS-BceAB of Bacillus subtilis as an example. To analyze the proposed communication between TCS and the ABC transporter, we characterized their interactions by bacterial two-hybrid analyses and could show that the permease BceB and the histidine kinase BceS interact directly. In vitro pulldown assays confirmed this interaction, which was found to be independent of bacitracin. Because it was unknown whether BceAB-type transporters could detect their substrate peptides directly or instead recognized the peptide-target complex in the cell envelope, we next analyzed substrate binding by the transport permease, BceB. Direct and specific binding of bacitracin by BceB was demonstrated by surface plasmon resonance spectroscopy. Finally, in vitro signal transduction assays indicated that complex formation with the transporter influenced the autophosphorylation activity of the histidine kinase. Taken together, our findings clearly show the existence of a sensory complex composed of TCS and ABC transporters and provide the first functional insights into the mechanisms of stimulus perception, signal transduction, and antimicrobial resistance employed by Bce-like detoxification systems.
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Affiliation(s)
| | | | - Chong Fang
- From the Department of Biology I, Microbiology, and
| | - Kirsten Jung
- From the Department of Biology I, Microbiology, and Munich Center for Integrated Protein Science, Ludwig-Maximilians-Universität München, 82152 Martinsried, Germany
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Abstract
The bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) is a multicomponent system that participates in a variety of physiological processes in addition to the phosphorylation-coupled transport of numerous sugars. In Escherichia coli and other enteric bacteria, enzyme IIA(Glc) (EIIA(Glc)) is known as the central processing unit of carbon metabolism and plays multiple roles, including regulation of adenylyl cyclase, the fermentation/respiration switch protein FrsA, glycerol kinase, and several non-PTS transporters, whereas the only known regulatory role of the E. coli histidine-containing phosphocarrier protein HPr is in the activation of glycogen phosphorylase. Because HPr is known to be more abundant than EIIA(Glc) in enteric bacteria, we assumed that there might be more regulatory mechanisms connected with HPr. The ligand fishing experiment in this study identified Rsd, an anti-sigma factor known to complex with σ(70) in stationary-phase cells, as an HPr-binding protein in E. coli. Only the dephosphorylated form of HPr formed a tight complex with Rsd and thereby inhibited complex formation between Rsd and σ(70). Dephosphorylated HPr, but not phosphorylated HPr, antagonized the inhibitory effect of Rsd on σ(70)-dependent transcriptions both in vivo and in vitro, and also influenced the competition between σ(70) and σ(S) for core RNA polymerase in the presence of Rsd. Based on these data, we propose that the anti-σ(70) activity of Rsd is regulated by the phosphorylation state-dependent interaction of HPr with Rsd.
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The general phosphotransferase system proteins localize to sites of strong negative curvature in bacterial cells. mBio 2013; 4:e00443-13. [PMID: 24129255 PMCID: PMC3812706 DOI: 10.1128/mbio.00443-13] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The bacterial cell poles are emerging as subdomains where many cellular activities take place, but the mechanisms for polar localization are just beginning to unravel. The general phosphotransferase system (PTS) proteins, enzyme I (EI) and HPr, which control preferential use of carbon sources in bacteria, were recently shown to localize near the Escherichia coli cell poles. Here, we show that EI localization does not depend on known polar constituents, such as anionic lipids or the chemotaxis receptors, and on the cell division machinery, nor can it be explained by nucleoid occlusion or localized translation. Detection of the general PTS proteins at the budding sites of endocytotic-like membrane invaginations in spherical cells and their colocalization with the negative curvature sensor protein DivIVA suggest that geometric cues underlie localization of the PTS system. Notably, the kinetics of glucose uptake by spherical and rod-shaped E. coli cells are comparable, implying that negatively curved “pole-like” sites support not only the localization but also the proper functioning of the PTS system in cells with different shapes. Consistent with the curvature-mediated localization model, we observed the EI protein from Bacillus subtilis at strongly curved sites in both B. subtilis and E. coli. Taken together, we propose that changes in cell architecture correlate with dynamic survival strategies that localize central metabolic systems like the PTS to subcellular domains where they remain active, thus maintaining cell viability and metabolic alertness. Despite their tiny size and the scarcity of membrane-bounded organelles, bacteria are capable of sorting macromolecules to distinct subcellular domains, thus optimizing functionality of vital processes. Understanding the cues that organize bacterial cells should provide novel insights into the complex organization of higher organisms. Previously, we have shown that the general proteins of the phosphotransferase system (PTS) signaling system, which governs utilization of carbon sources in bacteria, localize to the poles of Escherichia coli cells. Here, we show that geometric cues, i.e., strong negative membrane curvature, mediate positioning of the PTS proteins. Furthermore, localization to negatively curved regions seems to support the PTS functionality.
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Lee CR, Park YH, Kim YR, Peterkofsky A, Seok YJ. Phosphorylation-Dependent Mobility Shift of Proteins on SDS-PAGE is Due to Decreased Binding of SDS. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.7.2063] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Mannitol and the mannitol-specific enzyme IIB subunit activate Vibrio cholerae biofilm formation. Appl Environ Microbiol 2013; 79:4675-83. [PMID: 23728818 DOI: 10.1128/aem.01184-13] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Vibrio cholerae is a halophilic, Gram-negative rod found in marine environments. Strains that produce cholera toxin cause the diarrheal disease cholera. V. cholerae use a highly conserved, multicomponent signal transduction cascade known as the phosphoenolpyruvate phosphotransferase system (PTS) to regulate carbohydrate uptake and biofilm formation. Regulation of biofilm formation by the PTS is complex, involving many different regulatory pathways that incorporate distinct PTS components. The PTS consists of the general components enzyme I (EI) and histidine protein (HPr) and carbohydrate-specific enzymes II. Mannitol transport by V. cholerae requires the mannitol-specific EII (EII(Mtl)), which is expressed only in the presence of mannitol. Here we show that mannitol activates V. cholerae biofilm formation and transcription of the vps biofilm matrix exopolysaccharide synthesis genes. This regulation is dependent on mannitol transport. However, we show that, in the absence of mannitol, ectopic expression of the B subunit of EII(Mtl) is sufficient to activate biofilm accumulation. Mannitol, a common compatible solute and osmoprotectant of marine organisms, is a main photosynthetic product of many algae and is secreted by algal mats. We propose that the ability of V. cholerae to respond to environmental mannitol by forming a biofilm may play an important role in habitat selection.
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Lee CR, Park YH, Kim M, Kim YR, Park S, Peterkofsky A, Seok YJ. Reciprocal regulation of the autophosphorylation of enzyme INtr by glutamine and α-ketoglutarate in Escherichia coli. Mol Microbiol 2013; 88:473-85. [PMID: 23517463 DOI: 10.1111/mmi.12196] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2013] [Indexed: 11/28/2022]
Abstract
In addition to the phosphoenolpyruvate:sugar phosphotransferase system (sugar PTS), most proteobacteria possess a paralogous system (nitrogen phosphotransferase system, PTS(Ntr)). The first proteins in both pathways are enzymes (enzyme I(sugar) and enzyme I(Ntr)) that can be autophosphorylated by phosphoenolpyruvate. The most striking difference between enzyme I(sugar) and enzyme I(Ntr) is the presence of a GAF domain at the N-terminus of enzyme I(Ntr). Since the PTS(Ntr) was identified in 1995, it has been implicated in a variety of cellular processes in many proteobacteria and many of these regulations have been shown to be dependent on the phosphorylation state of PTS(Ntr) components. However, there has been little evidence that any component of this so-called PTS(Ntr) is directly involved in nitrogen metabolism. Moreover, a signal regulating the phosphorylation state of the PTS(Ntr) had not been uncovered. Here, we demonstrate that glutamine and α-ketoglutarate, the canonical signals of nitrogen availability, reciprocally regulate the phosphorylation state of the PTS(Ntr) by direct effects on enzyme I(Ntr) autophosphorylation and the GAF signal transduction domain is necessary for the regulation of enzyme I(Ntr) activity by the two signal molecules. Taken together, our results suggest that the PTS(Ntr) senses nitrogen availability.
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Affiliation(s)
- Chang-Ro Lee
- Department of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, 151-742, Korea
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36
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Erni B. The bacterial phosphoenolpyruvate: sugar phosphotransferase system (PTS): an interface between energy and signal transduction. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2012. [DOI: 10.1007/s13738-012-0185-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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37
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Govindarajan S, Nevo-Dinur K, Amster-Choder O. Compartmentalization and spatiotemporal organization of macromolecules in bacteria. FEMS Microbiol Rev 2012; 36:1005-22. [DOI: 10.1111/j.1574-6976.2012.00348.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 06/27/2012] [Accepted: 06/28/2012] [Indexed: 12/18/2022] Open
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Chemotactic signaling via carbohydrate phosphotransferase systems in Escherichia coli. Proc Natl Acad Sci U S A 2012; 109:12159-64. [PMID: 22778402 DOI: 10.1073/pnas.1205307109] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Chemotaxis allows bacteria to follow gradients of nutrients, environmental stimuli, and signaling molecules, optimizing bacterial growth and survival. Escherichia coli has long served as a model of bacterial chemotaxis, and the signal processing by the core of its chemotaxis pathway is well understood. However, most of the research so far has focused on one branch of chemotactic signaling, in which ligands bind to periplasmic sensory domains of transmembrane chemoreceptors and induce a conformational change that is transduced across the membrane to regulate activity of the receptor-associated kinase CheA. Here we quantitatively characterize another, receptor-independent branch of chemotactic signaling that is linked to the sugar uptake through a large family of phosphotransferase systems (PTSs). Using in vivo characterization of intracellular signaling and protein interactions, we demonstrate that signals from cytoplasmic PTS components are transmitted directly to the sensory complexes formed by chemoreceptors, CheA and an adapter protein CheW. We further conclude that despite different modes of sensing, the PTS- and receptor-mediated signals have similar regulatory effects on the conformation of the sensory complexes. As a consequence, both types of signals become integrated and undergo common downstream processing including methylation-dependent adaptation. We propose that such mode of signaling is essential for efficient chemotaxis to PTS substrates and may be common to most bacteria.
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Lazova MD, Butler MT, Shimizu TS, Harshey RM. Salmonella chemoreceptors McpB and McpC mediate a repellent response to L-cystine: a potential mechanism to avoid oxidative conditions. Mol Microbiol 2012; 84:697-711. [PMID: 22486902 DOI: 10.1111/j.1365-2958.2012.08051.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chemoreceptors McpB and McpC in Salmonella enterica have been reported to promote chemotaxis in LB motility-plate assays. Of the chemicals tested as potential effectors of these receptors, the only response was towards L-cysteine and its oxidized form, L-cystine. Although enhanced radial migration in plates suggested positive chemotaxis to both amino acids, capillary assays failed to show an attractant response to either, in cells expressing only these two chemoreceptors. In vivo fluorescence resonance energy transfer (FRET) measurements of kinase activity revealed that in wild-type bacteria, cysteine and cystine are chemoeffectors of opposing sign, the reduced form being a chemoattractant and the oxidized form a repellent. The attractant response to cysteine was mediated primarily by Tsr, as reported earlier for Escherichia coli. The repellent response to cystine was mediated by McpB/C. Adaptive recovery upon cystine exposure required the methyl-transferase/-esterase pair, CheR/CheB, but restoration of kinase activity was never complete (i.e. imperfect adaptation). We provide a plausible explanation for the attractant-like responses to both cystine and cysteine in motility plates, and speculate that the opposing signs of response to this redox pair might afford Salmonella a mechanism to gauge and avoid oxidative environments.
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Affiliation(s)
- Milena D Lazova
- FOM Institute for Atomic and Molecular Physics, 1098 XG Amsterdam, the Netherlands
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A dodecapeptide (YQVTQSKVMSHR) exhibits antibacterial effect and induces cell aggregation in Escherichia coli. Appl Microbiol Biotechnol 2012; 94:755-62. [PMID: 22314514 DOI: 10.1007/s00253-011-3857-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 12/15/2011] [Accepted: 12/20/2011] [Indexed: 10/14/2022]
Abstract
Antimicrobial peptides play an important role in the innate immune response and host defense mechanism. In the present study, we employed phage display technique to screen for inhibitors which may block the phosphoenolpyruvatedependent phosphotransferase system (PTS) pathway and hence retard cell growth. The recombinant histidine-containing phosphocarrier HPr protein was prepared as the target to screen for the tight binders from the phage-displayed random peptide library Ph.D.-12. The biopanning processes were performed and the binding capabilities of the selected phage were further estimated by enzyme-linked immunosorbent assay (ELISA). The single-stranded DNAs of the 20 selected phages were isolated, sequenced, and five corresponding peptides were synthesized. Only one of the five peptides, AP1 (YQVTQSK VMSHR) was found to inhibit the growth of Escherichia coli cells efficiently (IC₅₀~50 μM). Molecular modeling reveals that AP1 may block the EI-HPr interaction and phosphotransfer. Interestingly, AP1 was also found to induce cell aggregation in a concentration-dependent manner. Since glycogen accumulation has been attributed to biofilm formation, the effects of AP1 on the intracellular glycogen levels were measured. The results strongly indicate that the cell aggregation may be caused by the binding of peptide AP1 with HPr to block the interaction of dephosphorylated HPr with glycogen phosphorylase (GP). Because glycogen phosphorylase activity can be activated by HPr-GP interaction, the binding of AP1 to HPr would cause a decreasing rate of glycogen breakdown in M9 medium and accumulation of glycogen, which may lead to eventual cell aggregation. To the best of our knowledge, this is the first study to demonstrate that an inhibitor bound to a dephosphorylated HPr can decouple its regulatory function and induce cell aggregation.
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Bian F, Mao G, Guo M, Mao G, Wang J, Li J, Han Y, Chen X, Zhang M, Xia G. Gradients of natriuretic peptide precursor A (NPPA) in oviduct and of natriuretic peptide receptor 1 (NPR1) in spermatozoon are involved in mouse sperm chemotaxis and fertilization. J Cell Physiol 2012; 227:2230-9. [DOI: 10.1002/jcp.22962] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kim HJ, Lee CR, Kim M, Peterkofsky A, Seok YJ. Dephosphorylated NPr of the nitrogen PTS regulates lipid A biosynthesis by direct interaction with LpxD. Biochem Biophys Res Commun 2011; 409:556-61. [PMID: 21605551 DOI: 10.1016/j.bbrc.2011.05.044] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 05/07/2011] [Indexed: 10/18/2022]
Abstract
Bacterial phosphoenolpyruvate-dependent phosphotransferase systems (PTS) play multiple roles in addition to sugar transport. Recent studies revealed that enzyme IIA(Ntr) of the nitrogen PTS regulates the intracellular concentration of K(+) by direct interaction with TrkA and KdpD. In this study, we show that dephosphorylated NPr of the nitrogen PTS interacts with Escherichia coli LpxD which catalyzes biosynthesis of lipid A of the lipopolysaccharide (LPS) layer. Mutations in lipid A biosynthetic genes such as lpxD are known to confer hypersensitivity to hydrophobic antibiotics such as rifampin; a ptsO (encoding NPr) deletion mutant showed increased resistance to rifampin and increased LPS biosynthesis. Taken together, our data suggest that unphosphorylated NPr decreases lipid A biosynthesis by inhibiting LpxD activity.
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Affiliation(s)
- Hyun-Jin Kim
- Department of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul 151-742, Republic of Korea
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EI of the Phosphotransferase System of Escherichia coli: Mathematical Modeling Approach to Analysis of Its Kinetic Properties. JOURNAL OF BIOPHYSICS 2011; 2011:579402. [PMID: 21716653 PMCID: PMC3116621 DOI: 10.1155/2011/579402] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 01/20/2011] [Indexed: 11/17/2022]
Abstract
The mathematical model of the operation of the first enzyme of the Escherichia coli phosphotransferase system, EI, is proposed. Parameters of the kinetic model describing the operation of EI under different conditions are identified on the basis of a large amount of known experimental data. The verified model is employed to predict modes of operation of EI under both in vivo physiological conditions and in vitro nonphysiological conditions. The model predicts that under in vivo physiological conditions, the rate of phosphotransfer from EI to the second protein of the phosphotransferase system HPr by the dimer is much higher than by the monomer. A hypothesis is proposed on the basis of calculations that the transfer by a monomer plays a role in the regulation of chemotaxis. At submicromolar pyruvate concentration, the model predicts nonmonotonic dependence of the phosphotransfer rate on the substrate (PEP) concentration.
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Microbial removal of acetate selectively from sugar mixtures. J Ind Microbiol Biotechnol 2011; 38:1477-84. [PMID: 21225311 DOI: 10.1007/s10295-010-0932-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Accepted: 12/18/2010] [Indexed: 10/18/2022]
Abstract
Acetic acid is an unavoidable constituent of the biomass hydrolysates generated from acetylated hemicellulose and lignin, and acetate affects the performance of microbes used to convert these hydrolysates into biofuels or other biochemicals. In this study, acetate was selectively removed from synthetic mixtures of glucose and xylose using metabolically engineered Escherichia coli strains having mutations in the glucose phosphotransferase system (PTS) genes (ptsG, manZ, crr), glucokinase (glk), and xylose (xylA). In batch culture, ALS1060 (ptsG manZ glk xylA) consumed exclusively acetate to depletion, and then consumed the two sugars only at a very slow rate (a growth rate of about 0.01 h(-1)). We also examined the effects of an additional knockout of either malX, fruA, fruB, bglF, or crr, genes that are involved in other PTSs, and a batch process using KD840 (ptsG manZ glk crr xylA) demonstrated a further reduction in glucose or xylose consumption by E. coli. These results demonstrate the feasibility of using a substrate-selective approach for the pre-treatment of biomass hydrolysate for microbial processes.
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Lee CR, Cho SH, Kim HJ, Kim M, Peterkofsky A, Seok YJ. Potassium mediates Escherichia coli enzyme IIANtr-dependent regulation of sigma factor selectivity. Mol Microbiol 2010; 78:1468-83. [DOI: 10.1111/j.1365-2958.2010.07419.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Spatial and temporal organization of the E. coli PTS components. EMBO J 2010; 29:3630-45. [PMID: 20924357 DOI: 10.1038/emboj.2010.240] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2010] [Accepted: 09/06/2010] [Indexed: 01/25/2023] Open
Abstract
The phosphotransferase system (PTS) controls preferential use of sugars in bacteria. It comprises of two general proteins, enzyme I (EI) and HPr, and various sugar-specific permeases. Using fluorescence microscopy, we show here that EI and HPr localize near the Escherichia coli cell poles. Polar localization of each protein occurs independently, but HPr is released from the poles in an EI- and sugar-dependent manner. Conversely, the β-glucoside-specific permease, BglF, localizes to the cell membrane. EI, HPr and BglF control the β-glucoside utilization (bgl) operon by modulating the activity of the BglG transcription factor; BglF inactivates BglG by membrane sequestration and phosphorylation, whereas EI and HPr activate it by an unknown mechanism in response to β-glucosides availability. Using biochemical, genetic and imaging methodologies, we show that EI and HPr interact with BglG and affect its subcellular localization in a phosphorylation-independent manner. Upon sugar stimulation, BglG migrates from the cell periphery to the cytoplasm through the poles. Hence, the PTS components appear to control bgl operon expression by ushering BglG between the cellular compartments. Our results reinforce the notion that signal transduction in bacteria involves dynamic localization of proteins.
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Zurbriggen A, Schneider P, Bähler P, Baumann U, Erni B. Expression, purification, crystallization and preliminary X-ray analysis of the EIICGlc domain of the Escherichia coli glucose transporter. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:684-8. [PMID: 20516600 DOI: 10.1107/s1744309110013102] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Accepted: 04/08/2010] [Indexed: 11/11/2022]
Abstract
The glucose-import system of Escherichia coli consists of a hydrophilic EIIA(Glc) subunit and a transmembrane EIICB(Glc) subunit. EIICB(Glc) (UniProt P69786) contains two domains: the transmembrane EIIC(Glc) domain (40.6 kDa) and the cytoplasmic EIIB(Glc) domain (8.0 kDa), which are fused by a linker that is strongly conserved among its orthologues. The EIICB(Glc) subunit can be split within this motif by trypsin. Here, the crystallization of the tryptic EIIC(Glc) domain is described. A complete data set was collected to 4.5 A resolution at 100 K.
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Affiliation(s)
- Andreas Zurbriggen
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland.
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Furtwängler K, Tarasov V, Wende A, Schwarz C, Oesterhelt D. Regulation of phosphate uptake via Pst transporters in Halobacterium salinarum R1. Mol Microbiol 2010; 76:378-92. [PMID: 20199599 DOI: 10.1111/j.1365-2958.2010.07101.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The genome of the archaeon Halobacterium salinarum contains two copies of the pst (phosphate-specific transport) operon, the genes of which are related to well-studied bacterial homologues. Both operons (pst1 and pst2) were shown to be polycistronic and, when under P(i)-limited conditions, transcription initiated 1 bp upstream of the translational starts. Under P(i) saturation, the pst1 operon utilized an additional transcription start site 59 bp upstream of the first one. The leaderless pst1 transcript was found to be more efficiently translated than the leadered transcript. Promoter strengths differed significantly between the two operons and when P(i) levels changed. The basal pst1 promoter activity in P(i)-saturated conditions was minimal while the pst2 promoter was active. In contrast, phosphate limitation induced the pst1 operon threefold more than the pst2 operon. We identified basic and phosphate-dependent cis-acting elements in both promoters. Phosphate-uptake assays conducted with several Pst1 and Pst2 mutant strains revealed differences in the substrate affinities between the two transporters and also suggested that the P(i)-binding proteins PstS1 and PstS2 can interact with either of the two permease subunits of the transporters. The tactic behaviour of wild type and pst-deletion strains showed that the Pst1 transporter plays an important role for phosphate-directed chemotaxis.
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Affiliation(s)
- Katarina Furtwängler
- Max-Planck-Institute of Biochemistry, Department of Membrane Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
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Zimmer B, Hillmann A, Görke B. Requirements for the phosphorylation of theEscherichia coliEIIANtrproteinin vivo. FEMS Microbiol Lett 2008; 286:96-102. [DOI: 10.1111/j.1574-6968.2008.01262.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Jahreis K, Pimentel-Schmitt EF, Brückner R, Titgemeyer F. Ins and outs of glucose transport systems in eubacteria. FEMS Microbiol Rev 2008; 32:891-907. [PMID: 18647176 DOI: 10.1111/j.1574-6976.2008.00125.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Glucose is the classical carbon source that is used to investigate the transport, metabolism, and regulation of nutrients in bacteria. Many physiological phenomena like nutrient limitation, stress responses, production of antibiotics, and differentiation are inextricably linked to nutrition. Over the years glucose transport systems have been characterized at the molecular level in more than 20 bacterial species. This review aims to provide an overview of glucose uptake systems found in the eubacterial kingdom. In addition, it will highlight the diverse and sophisticated regulatory features of glucose transport systems.
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Affiliation(s)
- Knut Jahreis
- Department of Biology and Chemistry, University of Osnabrück, Osnabrück, Germany
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