1
|
Iyer A, Frallicciardi J, le Paige UBA, Narasimhan S, Luo Y, Sieiro PA, Syga L, van den Brekel F, Tran BM, Tjioe R, Schuurman-Wolters G, Stuart MCA, Baldus M, van Ingen H, Poolman B. The Structure and Function of the Bacterial Osmotically Inducible Protein Y. J Mol Biol 2024; 436:168668. [PMID: 38908784 DOI: 10.1016/j.jmb.2024.168668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 06/14/2024] [Accepted: 06/14/2024] [Indexed: 06/24/2024]
Abstract
The ability to adapt to osmotically diverse and fluctuating environments is critical to the survival and resilience of bacteria that colonize the human gut and urinary tract. Environmental stress often provides cross-protection against other challenges and increases antibiotic tolerance of bacteria. Thus, it is critical to understand how E. coli and other microbes survive and adapt to stress conditions. The osmotically inducible protein Y (OsmY) is significantly upregulated in response to hypertonicity. Yet its function remains unknown for decades. We determined the solution structure and dynamics of OsmY by nuclear magnetic resonance spectroscopy, which revealed that the two Bacterial OsmY and Nodulation (BON) domains of the protein are flexibly linked under low- and high-salinity conditions. In-cell solid-state NMR further indicates that there are no gross structural changes in OsmY as a function of osmotic stress. Using cryo-electron and super-resolution fluorescence microscopy, we show that OsmY attenuates plasmolysis-induced structural changes in E. coli and improves the time to growth resumption after osmotic upshift. Structure-guided mutational and functional studies demonstrate that exposed hydrophobic residues in the BON1 domain are critical for the function of OsmY. We find no evidence for membrane interaction of the BON domains of OsmY, contrary to current assumptions. Instead, at high ionic strength, we observe an interaction with the water channel, AqpZ. Thus, OsmY does not play a simple structural role in E. coli but may influence a cascade of osmoregulatory functions of the cell.
Collapse
Affiliation(s)
- Aditya Iyer
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands.
| | - Jacopo Frallicciardi
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Ulric B A le Paige
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Siddarth Narasimhan
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Yanzhang Luo
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Patricia Alvarez Sieiro
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Lukasz Syga
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Floris van den Brekel
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Buu Minh Tran
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Rendy Tjioe
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Gea Schuurman-Wolters
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Marc C A Stuart
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Marc Baldus
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Hugo van Ingen
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands.
| | - Bert Poolman
- Department of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands.
| |
Collapse
|
2
|
Un Jan Contreras S, Redfern LK, Maguire LW, Promi SI, Gardner CM. Small Interfering RNAs (siRNAs) Negatively Impact Growth and Gene Expression of Environmentally Relevant Bacteria in In Vitro Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:13856-13865. [PMID: 39066708 DOI: 10.1021/acs.est.4c01685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Rising global populations have amplified food scarcity and ushered in the development of genetically modified (GM) crops containing small interference RNAs (siRNAs) that control gene expression to overcome these challenges. The use of RNA interference (RNAi) in agriculture remains controversial due to uncertainty regarding the unintended release of genetic material and downstream nontarget effects, which have not been assessed in environmental bacteria to date. To evaluate the impacts of siRNAs used in agriculture on environmental bacteria, this study assessed microbial growth and viability as well as transcription activity with and without the presence of environmental stressors. Results showed a statistically significant reduction in growth capacity and maximum biomass achieved when bacteria are exposed to siRNAs alone and with additional external stress (p < 0.05). Further transcriptomic analysis demonstrated that nutrient cycling gene activities were found to be consistently and significantly altered following siRNA exposure, particularly among carbon (xylA, FBPase, limEH, Chitinase, rgl, rgh, rgaE, mannanase, ara) and nitrogen (ureC, nasA, narB, narG, nirK) cycling genes (p < 0.05). Decreases in carbon cycling gene transcription profiles were generally significantly enhanced when siRNA exposure was coupled with nutrient or antimicrobial stress. Collectively, findings suggest that certain conditions facilitate the uptake of siRNAs from their surrounding environments that can negatively affect bacterial growth and gene expression activity, with uncertain downstream impacts on ecosystem homeostasis.
Collapse
Affiliation(s)
- S Un Jan Contreras
- Department of Civil and Environmental Engineering, Washington State University, 405 Spokane St., Pullman, Washington 99164, United States
| | - L K Redfern
- Department of Bioengineering, Civil Engineering, and Environmental Engineering, Florida Gulf Coast University, 10501 FGCU Blvd., Fort Myers, Florida 33965, United States
| | - L W Maguire
- Maseeh Department of Civil, Architectural, and Environmental Engineering, University of Texas at Austin, 301E E Dean Keeton St c1700, Austin, Texas 78712, United States
| | - S I Promi
- Maseeh Department of Civil, Architectural, and Environmental Engineering, University of Texas at Austin, 301E E Dean Keeton St c1700, Austin, Texas 78712, United States
| | - C M Gardner
- Department of Civil and Environmental Engineering, Washington State University, 405 Spokane St., Pullman, Washington 99164, United States
- Maseeh Department of Civil, Architectural, and Environmental Engineering, University of Texas at Austin, 301E E Dean Keeton St c1700, Austin, Texas 78712, United States
| |
Collapse
|
3
|
Al Mamun AAM, Kissoon K, Li YG, Hancock E, Christie PJ. The F plasmid conjutome: the repertoire of E. coli proteins translocated through an F-encoded type IV secretion system. mSphere 2024; 9:e0035424. [PMID: 38940509 PMCID: PMC11288057 DOI: 10.1128/msphere.00354-24] [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: 04/25/2024] [Accepted: 06/10/2024] [Indexed: 06/29/2024] Open
Abstract
Bacterial conjugation systems pose a major threat to human health through their widespread dissemination of mobile genetic elements (MGEs) carrying cargoes of antibiotic resistance genes. Using the Cre Recombinase Assay for Translocation (CRAfT), we recently reported that the IncFV pED208 conjugation system also translocates at least 16 plasmid-encoded proteins to recipient bacteria. Here, we deployed a high-throughput CRAfT screen to identify the repertoire of chromosomally encoded protein substrates of the pED208 system. We identified 32 substrates encoded by the Escherichia coli W3110 genome with functions associated with (i) DNA/nucleotide metabolism, (ii) stress tolerance/physiology, (iii) transcriptional regulation, or (iv) toxin inhibition. The respective gene deletions did not impact pED208 transfer proficiencies, nor did Group 1 (DNA/nucleotide metabolism) mutations detectably alter the SOS response elicited in new transconjugants upon acquisition of pED208. However, MC4100(pED208) donor cells intrinsically exhibit significantly higher SOS activation than plasmid-free MC4100 cells, and this plasmid carriage-induced stress response is further elevated in donor cells deleted of several Group 1 genes. Among 10 characterized substrates, we gained evidence of C-terminal or internal translocation signals that could function independently or synergistically for optimal protein transfer. Remarkably, nearly all tested proteins were also translocated through the IncN pKM101 and IncP RP4 conjugation systems. This repertoire of E. coli protein substrates, here termed the F plasmid "conjutome," is thus characterized by functions of potential benefit to new transconjugants, diverse TSs, and the capacity for promiscuous transfer through heterologous conjugation systems. IMPORTANCE Conjugation systems comprise a major subfamily of the type IV secretion systems (T4SSs) and are the progenitors of a second large T4SS subfamily dedicated to translocation of protein effectors. This study examined the capacity of conjugation machines to function as protein translocators. Using a high-throughput reporter screen, we determined that 32 chromosomally encoded proteins are delivered through an F plasmid conjugation system. The translocated proteins potentially enhance the establishment of the co-transferred F plasmid or mitigate mating-induced stresses. Translocation signals located C-terminally or internally conferred substrate recognition by the F system and, remarkably, many substrates also were translocated through heterologous conjugation systems. Our findings highlight the plasticity of conjugation systems in their capacities to co-translocate DNA and many protein substrates.
Collapse
Affiliation(s)
- Abu Amar M. Al Mamun
- Department of Microbiology and Molecular Genetics, McGovern Medical School at UTHealth, Houston, Texas, USA
| | - Kimberley Kissoon
- Department of Microbiology and Molecular Genetics, McGovern Medical School at UTHealth, Houston, Texas, USA
| | - Yang Grace Li
- Department of Microbiology and Molecular Genetics, McGovern Medical School at UTHealth, Houston, Texas, USA
| | - Erin Hancock
- Department of Microbiology and Molecular Genetics, McGovern Medical School at UTHealth, Houston, Texas, USA
| | - Peter J. Christie
- Department of Microbiology and Molecular Genetics, McGovern Medical School at UTHealth, Houston, Texas, USA
| |
Collapse
|
4
|
Ousalem F, Ngo S, Oïffer T, Omairi-Nasser A, Hamon M, Monlezun L, Boël G. Global regulation via modulation of ribosome pausing by the ABC-F protein EttA. Nat Commun 2024; 15:6314. [PMID: 39060293 PMCID: PMC11282234 DOI: 10.1038/s41467-024-50627-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 07/10/2024] [Indexed: 07/28/2024] Open
Abstract
Having multiple rounds of translation of the same mRNA creates dynamic complexities along with opportunities for regulation related to ribosome pausing and stalling at specific sequences. Yet, mechanisms controlling these critical processes and the principles guiding their evolution remain poorly understood. Through genetic, genomic, physiological, and biochemical approaches, we demonstrate that regulating ribosome pausing at specific amino acid sequences can produce ~2-fold changes in protein expression levels which strongly influence cell growth and therefore evolutionary fitness. We demonstrate, both in vivo and in vitro, that the ABC-F protein EttA directly controls the translation of mRNAs coding for a subset of enzymes in the tricarboxylic acid (TCA) cycle and its glyoxylate shunt, which modulates growth in some chemical environments. EttA also modulates expression of specific proteins involved in metabolically related physiological and stress-response pathways. These regulatory activities are mediated by EttA rescuing ribosomes paused at specific patterns of negatively charged residues within the first 30 amino acids of nascent proteins. We thus establish a unique global regulatory paradigm based on sequence-specific modulation of translational pausing.
Collapse
Affiliation(s)
- Farès Ousalem
- Expression Génétique Microbienne, CNRS, Université Paris Cité, Institut de Biologie Physico-Chimique, Paris, France
- Biomarqueurs et nouvelles cibles thérapeutiques en oncologie, INSERM U981, Université Paris Saclay, Institut de Cancérologie Gustave Roussy, Villejuif Cedex, France
| | - Saravuth Ngo
- Expression Génétique Microbienne, CNRS, Université Paris Cité, Institut de Biologie Physico-Chimique, Paris, France
| | - Thomas Oïffer
- Expression Génétique Microbienne, CNRS, Université Paris Cité, Institut de Biologie Physico-Chimique, Paris, France
| | - Amin Omairi-Nasser
- Expression Génétique Microbienne, CNRS, Université Paris Cité, Institut de Biologie Physico-Chimique, Paris, France
| | - Marion Hamon
- CNRS, Institut de Biologie Physico-Chimique, Plateforme de Protéomique, FR550, Paris, France
| | - Laura Monlezun
- Expression Génétique Microbienne, CNRS, Université Paris Cité, Institut de Biologie Physico-Chimique, Paris, France
| | - Grégory Boël
- Expression Génétique Microbienne, CNRS, Université Paris Cité, Institut de Biologie Physico-Chimique, Paris, France.
| |
Collapse
|
5
|
Rojano-Nisimura AM, Grismore KB, Ruzek JS, Avila JL, Contreras LM. The Post-Transcriptional Regulatory Protein CsrA Amplifies Its Targetome through Direct Interactions with Stress-Response Regulatory Hubs: The EvgA and AcnA Cases. Microorganisms 2024; 12:636. [PMID: 38674581 PMCID: PMC11052181 DOI: 10.3390/microorganisms12040636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 03/08/2024] [Accepted: 03/19/2024] [Indexed: 04/28/2024] Open
Abstract
Global rewiring of bacterial gene expressions in response to environmental cues is mediated by regulatory proteins such as the CsrA global regulator from E. coli. Several direct mRNA and sRNA targets of this protein have been identified; however, high-throughput studies suggest an expanded RNA targetome for this protein. In this work, we demonstrate that CsrA can extend its network by directly binding and regulating the evgA and acnA transcripts, encoding for regulatory proteins. CsrA represses EvgA and AcnA expression and disrupting the CsrA binding sites of evgA and acnA, results in broader gene expression changes to stress response networks. Specifically, altering CsrA-evgA binding impacts the genes related to acidic stress adaptation, and disrupting the CsrA-acnA interaction affects the genes involved in metal-induced oxidative stress responses. We show that these interactions are biologically relevant, as evidenced by the improved tolerance of evgA and acnA genomic mutants depleted of CsrA binding sites when challenged with acid and metal ions, respectively. We conclude that EvgA and AcnA are intermediate regulatory hubs through which CsrA can expand its regulatory role. The indirect CsrA regulation of gene networks coordinated by EvgA and AcnA likely contributes to optimizing cellular resources to promote exponential growth in the absence of stress.
Collapse
Affiliation(s)
| | - Kobe B. Grismore
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E. Dean Keeton St. Stop C0400, Austin, TX 78712, USA; (K.B.G.); (J.S.R.); (J.L.A.)
| | - Josie S. Ruzek
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E. Dean Keeton St. Stop C0400, Austin, TX 78712, USA; (K.B.G.); (J.S.R.); (J.L.A.)
| | - Jacqueline L. Avila
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E. Dean Keeton St. Stop C0400, Austin, TX 78712, USA; (K.B.G.); (J.S.R.); (J.L.A.)
| | - Lydia M. Contreras
- Department of Molecular Biosciences, The University of Texas at Austin, 100 East 24th St. Stop A5000, Austin, TX 78712, USA;
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E. Dean Keeton St. Stop C0400, Austin, TX 78712, USA; (K.B.G.); (J.S.R.); (J.L.A.)
| |
Collapse
|
6
|
Wang Z, Lu K, Liu X, Zhu Y, Liu C. Comparative Functional Genome Analysis Reveals the Habitat Adaptation and Biocontrol Characteristics of Plant Growth-Promoting Bacteria in NCBI Databases. Microbiol Spectr 2023; 11:e0500722. [PMID: 37098923 PMCID: PMC10269705 DOI: 10.1128/spectrum.05007-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 04/03/2023] [Indexed: 04/27/2023] Open
Abstract
Plant growth-promoting bacteria (PGPB) are a group of beneficial microorganisms that include 60 bacterial genera, such as Bacillus, Pseudomonas, and Burkholderia, which widely colonize plant leaves and soil, promote plant growth, and/or inhibit pathogen infection. However, the genetic factors underpinning adaptation of PGPB to plant leaves and soil remain poorly understood. In this study, we performed a comparative functional genome analysis approach to investigate the functional genes of 195 leaf-associated (LA) and 283 soil-associated (SA) PGPB strains and their roles in adapting to their environment, using 95 strains from other-associated (OA) environmental habitats with growth-promoting or antimicrobial functions as negative controls. Comparison analysis of the enrichment of nonredundant (NR) protein sequence databases showed that cytochrome P450, DNA repair, and motor chemotaxis genes were significantly enriched in LA PGPB strains related to environmental adaptation, while cell wall-degrading enzymes, TetR transcriptional regulatory factors, and sporulation-related genes were highly enriched in SA PGPB strains. Additionally, analysis of carbohydrate-active enzymes demonstrated that glycosyltransferases (GTs) and glycoside hydrolases (GHs) were abundant families in all PGPB strains, which is in favor of plant growth, and enriched in SA PGPB strains. Except for most Bacillus strains, SA PGPB genomes contained significantly more secondary metabolism clusters than LA PGPB. Most LA PGPB contained hormone biosynthesis genes, which may contribute to plant growth promotion, while SA PGPB harbored numerous carbohydrate and antibiotic metabolism genes. In summary, this study further deepens our understanding of the habitat adaptation and biocontrol characteristics of LA and SA PGPB strains. IMPORTANCE Plant growth-promoting bacteria (PGPB) are essential for the effectiveness of biocontrol agents in plant phyllosphere and rhizosphere. However, little is known about the ecological adaptation of PGPB to different habitats. In this study, comparative functional genome analysis of leaf-associated (LA), soil-associated (SA), and other-associated (OA) PGPB strains was performed. We found that genes related to the metabolism of hormones were enriched in LA PGPB. Carbohydrate and antibiotic metabolism genes were enriched in SA PGPB, which likely facilitated their adaptation to the plant growth environment. Our findings provide genetic insights on LA and SA PGPB strains' ecological adaptation and biocontrol characteristics.
Collapse
Affiliation(s)
- Zhen Wang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Kaiheng Lu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Xuan Liu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Yuping Zhu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Changhong Liu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| |
Collapse
|
7
|
Loiko N, Tereshkina K, Kovalenko V, Moiseenko A, Tereshkin E, Sokolova OS, Krupyanskii Y. DNA-Binding Protein Dps Protects Escherichia coli Cells against Multiple Stresses during Desiccation. BIOLOGY 2023; 12:853. [PMID: 37372138 DOI: 10.3390/biology12060853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 06/06/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023]
Abstract
Gradual dehydration is one of the frequent lethal yet poorly understood stresses that bacterial cells constantly face in the environment when their micro ecotopes dry out, as well as in industrial processes. Bacteria successfully survive extreme desiccation through complex rearrangements at the structural, physiological, and molecular levels, in which proteins are involved. The DNA-binding protein Dps has previously been shown to protect bacterial cells from many adverse effects. In our work, using engineered genetic models of E. coli to produce bacterial cells with overproduction of Dps protein, the protective function of Dps protein under multiple desiccation stresses was demonstrated for the first time. It was shown that the titer of viable cells after rehydration in the experimental variants with Dps protein overexpression was 1.5-8.5 times higher. Scanning electron microscopy was used to show a change in cell morphology upon rehydration. It was also proved that immobilization in the extracellular matrix, which is greater when the Dps protein is overexpressed, helps the cells survive. Transmission electron microscopy revealed disruption of the crystal structure of DNA-Dps crystals in E. coli cells that underwent desiccation stress and subsequent watering. Coarse-grained molecular dynamics simulations showed the protective function of Dps in DNA-Dps co-crystals during desiccation. The data obtained are important for improving biotechnological processes in which bacterial cells undergo desiccation.
Collapse
Affiliation(s)
- Nataliya Loiko
- Winogradsky Institute of Microbiology, Fundamentals of Biotechnology Federal Research Center, Russian Academy of Sciences, 117312 Moscow, Russia
| | - Ksenia Tereshkina
- Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Vladislav Kovalenko
- Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Andrey Moiseenko
- Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Eduard Tereshkin
- Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Olga S Sokolova
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Yurii Krupyanskii
- Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia
| |
Collapse
|
8
|
Shaffer JMC, Giddings LA, Samples RM, Mikucki JA. Genomic and phenotypic characterization of a red-pigmented strain of Massilia frigida isolated from an Antarctic microbial mat. Front Microbiol 2023; 14:1156033. [PMID: 37250028 PMCID: PMC10213415 DOI: 10.3389/fmicb.2023.1156033] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 04/20/2023] [Indexed: 05/31/2023] Open
Abstract
The McMurdo Dry Valleys of Antarctica experience a range of selective pressures, including extreme seasonal variation in temperature, water and nutrient availability, and UV radiation. Microbial mats in this ecosystem harbor dense concentrations of biomass in an otherwise desolate environment. Microbial inhabitants must mitigate these selective pressures via specialized enzymes, changes to the cellular envelope, and the production of secondary metabolites, such as pigments and osmoprotectants. Here, we describe the isolation and characterization of a Gram-negative, rod-shaped, motile, red-pigmented bacterium, strain DJPM01, from a microbial mat within the Don Juan Pond Basin of Wright Valley. Analysis of strain DJMP01's genome indicates it can be classified as a member of the Massilia frigida species. The genome contains several genes associated with cold and salt tolerance, including multiple RNA helicases, protein chaperones, and cation/proton antiporters. In addition, we identified 17 putative secondary metabolite gene clusters, including a number of nonribosomal peptides and ribosomally synthesized and post-translationally modified peptides (RiPPs), among others, and the biosynthesis pathway for the antimicrobial pigment prodigiosin. When cultivated on complex agar, multiple prodiginines, including the antibiotic prodigiosin, 2-methyl-3-propyl-prodiginine, 2-methyl-3-butyl-prodiginine, 2-methyl-3-heptyl-prodiginine, and cycloprodigiosin, were detected by LC-MS. Genome analyses of sequenced members of the Massilia genus indicates prodigiosin production is unique to Antarctic strains. UV-A radiation, an ecological stressor in the Antarctic, was found to significantly decrease the abundance of prodiginines produced by strain DJPM01. Genomic and phenotypic evidence indicates strain DJPM01 can respond to the ecological conditions of the DJP microbial mat, with prodiginines produced under a range of conditions, including extreme UV radiation.
Collapse
Affiliation(s)
- Jacob M. C. Shaffer
- Department of Microbiology, University of Tennessee, Knoxville, TN, United States
| | | | - Robert M. Samples
- Department of Chemistry, Smith College, Northampton, MA, United States
| | - Jill A. Mikucki
- Department of Microbiology, University of Tennessee, Knoxville, TN, United States
| |
Collapse
|
9
|
Murashko ON, Yeh KH, Yu CHA, Kaberdin VR, Lin-Chao S. Sodium Fluoride Exposure Leads to ATP Depletion and Altered RNA Decay in Escherichia coli under Anaerobic Conditions. Microbiol Spectr 2023; 11:e0415822. [PMID: 36939343 PMCID: PMC10100675 DOI: 10.1128/spectrum.04158-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 02/11/2023] [Indexed: 03/21/2023] Open
Abstract
Although fluoride-containing compounds are widely used to inhibit bacterial growth, the reprogramming of gene expression underlying cellular responses to fluoride, especially under anaerobic conditions, is still poorly understood. Here, we compare the genome-wide transcriptomic profiles of E. coli grown in the absence (control) or presence (20 and 70 mM) of sodium fluoride (NaF) under anaerobic conditions and assess the impact of fluoride-dependent ATP depletion on RNA turnover. Tiling array analysis revealed transcripts displaying altered abundance in response to NaF treatments. Quantile-based K-means clustering uncovered a subset of genes that were highly upregulated and then downregulated in response to increased and subsequently decreased fluoride concentrations, many of which (~40%) contained repetitive extragenic palindromic (REP) sequences. Northern blot analysis of some of these highly upregulated REP-containing transcripts (i.e., osmC, proP, efeO and yghA) confirmed their considerably enhanced abundance in response to NaF treatment. An mRNA stability analysis of osmC and yghA transcripts demonstrated that fluoride treatment slows down RNA degradation, thereby enhancing RNA stability and steady-state mRNA levels. Moreover, we demonstrate that turnover of these transcripts depends on RNase E activity and RNA degradosome. Thus, we show that NaF exerts significant effects at the whole-transcriptome level under hypoxic growth (i.e., mimicking the host environment), and fluoride can impact gene expression posttranscriptionally by slowing down ATP-dependent degradation of structured RNAs. IMPORTANCE Gram-negative Escherichia coli is a rod-shaped facultative anaerobic bacterium commonly found in microaerobic/anaerobic environments, including the dental plaques of warm-blooded organisms. These latter can be treated efficiently with fluoride-rich compounds that act as anticaries agents to prevent tooth decay. Although fluoride inhibits microbial growth by affecting metabolic pathways, the molecular mechanisms underlying its activity under anaerobic conditions remain poorly defined. Here, using genome-wide transcriptomics, we explore the impact of fluoride treatments on E. coli gene expression under anaerobic conditions. We reveal key gene clusters associated with cellular responses to fluoride and define its ATP-dependent stabilizing effects on transcripts containing repetitive extragenic palindromic sequences. We demonstrate the mechanisms controlling the RNA stability of these REP-containing mRNAs. Thus, fluoride can affect gene expression posttranscriptionally by stabilizing structured RNAs.
Collapse
Affiliation(s)
| | - Kun-Hai Yeh
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | | | - Vladimir R. Kaberdin
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- Department of Immunology, Microbiology and Parasitology, University of the Basque Country UPV/EHU, Leioa, Spain
- Basque Foundation for Science, IKERBASQUE, Bilbao, Spain
- Research Centre for Experimental Marine Biology and Biotechnology (PIE-UPV/EHU), Plentzia, Spain
| | - Sue Lin-Chao
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| |
Collapse
|
10
|
Connor A, Wigham C, Bai Y, Rai M, Nassif S, Koffas M, Zha RH. Novel insights into construct toxicity, strain optimization, and primary sequence design for producing recombinant silk fibroin and elastin-like peptide in E. coli. Metab Eng Commun 2023; 16:e00219. [PMID: 36825067 PMCID: PMC9941211 DOI: 10.1016/j.mec.2023.e00219] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/06/2022] [Accepted: 01/24/2023] [Indexed: 02/05/2023] Open
Abstract
Spider silk proteins (spidroins) are a remarkable class of biomaterials that exhibit a unique combination of high-value attributes and can be processed into numerous morphologies for targeted applications in diverse fields. Recombinant production of spidroins represents the most promising route towards establishing the industrial production of the material, however, recombinant spider silk production suffers from fundamental difficulties that includes low titers, plasmid instability, and translational inefficiencies. In this work, we sought to gain a deeper understanding of upstream bottlenecks that exist in the field through the production of a panel of systematically varied spidroin sequences in multiple E. coli strains. A restriction on basal expression and specific genetic mutations related to stress responses were identified as primary factors that facilitated higher titers of the recombinant silk constructs. Using these findings, a novel strain of E. coli was created that produces recombinant silk constructs at levels 4-33 times higher than standard BL21(DE3). However, these findings did not extend to a similar recombinant protein, an elastin-like peptide. It was found that the recombinant silk proteins, but not the elastin-like peptide, exert toxicity on the E. coli host system, possibly through their high degree of intrinsic disorder. Along with strain engineering, a bioprocess design that utilizes longer culturing times and attenuated induction was found to raise recombinant silk titers by seven-fold and mitigate toxicity. Targeted alteration to the primary sequence of the recombinant silk constructs was also found to mitigate toxicity. These findings identify multiple points of focus for future work seeking to further optimize the recombinant production of silk proteins and is the first work to identify the intrinsic disorder and subsequent toxicity of certain spidroin constructs as a primary factor related to the difficulties of production.
Collapse
Affiliation(s)
- Alexander Connor
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Caleb Wigham
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Yang Bai
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Manish Rai
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Sebastian Nassif
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Mattheos Koffas
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Corresponding author. Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA.
| | - R. Helen Zha
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Corresponding author. Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA.
| |
Collapse
|
11
|
Adaptation of Lacticaseibacillus rhamnosus CM MSU 529 to Aerobic Growth: A Proteomic Approach. Microorganisms 2023; 11:microorganisms11020313. [PMID: 36838278 PMCID: PMC9963975 DOI: 10.3390/microorganisms11020313] [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: 12/27/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 01/27/2023] Open
Abstract
The study describes the effect of aerobic conditions on the proteome of homofermentative lactic acid bacterium Lacticaseibacillus rhamnosus CM MSU 529 grown in a batch culture. Aeration caused the induction of the biosynthesis of 43 proteins, while 14 proteins were downregulated as detected by label-free LC-MS/MS. Upregulated proteins are involved in oxygen consumption (Pox, LctO, pyridoxine 5'-phosphate oxidase), xylulose 5-phosphate conversion (Xfp), pyruvate metabolism (PdhD, AlsS, AlsD), reactive oxygen species (ROS) elimination (Tpx, TrxA, Npr), general stress response (GroES, PfpI, universal stress protein, YqiG), antioxidant production (CysK, DkgA), pyrimidine metabolism (CarA, CarB, PyrE, PyrC, PyrB, PyrR), oligopeptide transport and metabolism (OppA, PepO), and maturation and stability of ribosomal subunits (RbfA, VicX). Downregulated proteins participate in ROS defense (AhpC), citrate and pyruvate consumption (CitE, PflB), oxaloacetate production (AvtA), arginine synthesis (ArgG), amino acid transport (GlnQ), and deoxynucleoside biosynthesis (RtpR). The data obtained shed light on mechanisms providing O2-tolerance and adaptation to aerobic conditions in strain CM MSU 529. The biosynthesis of 39 from 57 differentially abundant proteins was shown to be O2-sensitive in lactic acid bacteria for the first time. To our knowledge this is the first study on the impact of aerobic cultivation on the proteome of L. rhamnosus.
Collapse
|
12
|
Glover G, Voliotis M, Łapińska U, Invergo BM, Soanes D, O'Neill P, Moore K, Nikolic N, Petrov PG, Milner DS, Roy S, Heesom K, Richards TA, Tsaneva-Atanasova K, Pagliara S. Nutrient and salt depletion synergistically boosts glucose metabolism in individual Escherichia coli cells. Commun Biol 2022; 5:385. [PMID: 35444215 PMCID: PMC9021252 DOI: 10.1038/s42003-022-03336-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/30/2022] [Indexed: 12/16/2022] Open
Abstract
The interaction between a cell and its environment shapes fundamental intracellular processes such as cellular metabolism. In most cases growth rate is treated as a proximal metric for understanding the cellular metabolic status. However, changes in growth rate might not reflect metabolic variations in individuals responding to environmental fluctuations. Here we use single-cell microfluidics-microscopy combined with transcriptomics, proteomics and mathematical modelling to quantify the accumulation of glucose within Escherichia coli cells. In contrast to the current consensus, we reveal that environmental conditions which are comparatively unfavourable for growth, where both nutrients and salinity are depleted, increase glucose accumulation rates in individual bacteria and population subsets. We find that these changes in metabolic function are underpinned by variations at the translational and posttranslational level but not at the transcriptional level and are not dictated by changes in cell size. The metabolic response-characteristics identified greatly advance our fundamental understanding of the interactions between bacteria and their environment and have important ramifications when investigating cellular processes where salinity plays an important role.
Collapse
Affiliation(s)
- Georgina Glover
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
- Department of Physics and Astronomy, University of Exeter, Stocker Road, Exeter, EX4 4QL, UK
| | - Margaritis Voliotis
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
- Department of Mathematics, University of Exeter, Stocker Road, Exeter, UK
| | - Urszula Łapińska
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
- Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4Q, UK
| | - Brandon M Invergo
- Translational Research Exchange at Exeter, University of Exeter, Exeter, UK
| | - Darren Soanes
- Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4Q, UK
| | - Paul O'Neill
- Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4Q, UK
| | - Karen Moore
- Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4Q, UK
| | - Nela Nikolic
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
- Institute of Science and Technology Austria, 3400, Klosterneuburg, Austria
| | - Peter G Petrov
- Department of Physics and Astronomy, University of Exeter, Stocker Road, Exeter, EX4 4QL, UK
| | - David S Milner
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, UK
| | - Sumita Roy
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
- Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4Q, UK
| | - Kate Heesom
- University of Bristol Proteomics Facility, University Walk, Bristol, BS8 1TD, UK
| | - Thomas A Richards
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, UK
| | - Krasimira Tsaneva-Atanasova
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
- Department of Mathematics, University of Exeter, Stocker Road, Exeter, UK
- Department of Bioinformatics and Mathematical Modelling, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, 105 Acad. G. Bonchev Str., 1113, Sofia, Bulgaria
| | - Stefano Pagliara
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK.
- Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4Q, UK.
| |
Collapse
|
13
|
The Cell Membrane of a Novel Rhizobium phaseoli Strain Is the Crucial Target for Aluminium Toxicity and Tolerance. Cells 2022; 11:cells11050873. [PMID: 35269493 PMCID: PMC8909678 DOI: 10.3390/cells11050873] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 02/17/2022] [Accepted: 02/28/2022] [Indexed: 01/01/2023] Open
Abstract
Soils with low pH and high aluminium (Al) contamination restrict common bean production, mainly due to adverse effects on rhizobia. We isolated a novel rhizobium strain, B3, from Kenyan soil which is more tolerant to Al stress than the widely used commercial strain CIAT899. B3 was resistant to 50 µM Al and recovered from 100 µM Al stress, while CIAT899 did not. Calcein labeling showed that less Al binds to the B3 membranes and less ATP and mScarlet-1 protein, a cytoplasmic marker, leaked out of B3 than CIAT899 cells in Al-containing media. Expression profiles showed that the primary targets of Al are genes involved in membrane biogenesis, metal ions binding and transport, carbohydrate, and amino acid metabolism and transport. The identified differentially expressed genes suggested that the intracellular γ-aminobutyric acid (GABA), glutathione (GSH), and amino acid levels, as well as the amount of the extracellular exopolysaccharide (EPS), might change during Al stress. Altered EPS levels could also influence biofilm formation. Therefore, these parameters were investigated in more detail. The GABA levels, extracellular EPS production, and biofilm formation increased, while GSH and amino acid level decreased. In conclusion, our comparative analysis identified genes that respond to Al stress in R. phaseoli. It appears that a large portion of the identified genes code for proteins stabilizing the plasma membrane. These genes might be helpful for future studies investigating the molecular basis of Al tolerance and the characterization of candidate rhizobial isolates that perform better in Al-contaminated soils than commercial strains.
Collapse
|
14
|
Lakshmi SA, Prasath KG, Tamilmuhilan K, Srivathsan A, Shafreen RMB, Kasthuri T, Pandian SK. Suppression of Thiol-Dependent Antioxidant System and Stress Response in Methicillin-Resistant Staphylococcus aureus by Docosanol: Explication Through Proteome Investigation. Mol Biotechnol 2022; 64:575-589. [PMID: 35018617 DOI: 10.1007/s12033-021-00434-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 12/01/2021] [Indexed: 11/28/2022]
Abstract
The present study was aimed to investigate the effect of docosanol on the protein expression profile of methicillin-resistant Staphylococcus aureus (MRSA). Thus, two-dimensional gel electrophoresis coupled with MALDI-TOF MS technique was utilized to identify the differentially regulated proteins in the presence of docosanol. A total of 947 protein spots were identified from the intracellular proteome of both control and docosanol treated samples among which 40 spots were differentially regulated with a fold change greater than 1.0. Prominently, the thiol-dependent antioxidant system and stress response proteins are downregulated in MRSA, which are critical for survival during oxidative stress. In particular, docosanol downregulated the expression of Tpx, AhpC, BshC, BrxA, and YceI with a fold change of 1.4 (p = 0.02), 1.4 (p = 0.01), 1.6 (p = 0.002), 4.9 (p = 0.02), and 1.4 (p = 0.02), respectively. In addition, docosanol reduced the expression of proteins involved in purine metabolic pathways, biofilm growth cycle, and virulence factor production. Altogether, these findings suggest that docosanol could efficiently target the antioxidant pathway by reducing the expression of bacillithiol and stress-associated proteins.
Collapse
Affiliation(s)
- Selvaraj Alagu Lakshmi
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, 630003, India
| | - Krishnan Ganesh Prasath
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, 630003, India
- Department of Biotechnology, Sri Venkateswara College of Engineering, Sriperumbudur, Tamil Nadu, 602117, India
| | - Kannapiran Tamilmuhilan
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, 630003, India
| | - Adimoolam Srivathsan
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, 630003, India
| | - Raja Mohamed Beema Shafreen
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, 630003, India
- Department of Biotechnology, Dr. Umayal Ramanathan College for Women, Alagappapuram, Karaikudi, Tamil Nadu, 630003, India
| | - Thirupathi Kasthuri
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, 630003, India
| | | |
Collapse
|
15
|
|
16
|
Evaluation of RNA later as a Field-Compatible Preservation Method for Metaproteomic Analyses of Bacterium-Animal Symbioses. Microbiol Spectr 2021; 9:e0142921. [PMID: 34704828 PMCID: PMC8549751 DOI: 10.1128/spectrum.01429-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Field studies are central to environmental microbiology and microbial ecology, because they enable studies of natural microbial communities. Metaproteomics, the study of protein abundances in microbial communities, allows investigators to study these communities "in situ," which requires protein preservation directly in the field because protein abundance patterns can change rapidly after sampling. Ideally, a protein preservative for field deployment works rapidly and preserves the whole proteome, is stable in long-term storage, is nonhazardous and easy to transport, and is available at low cost. Although these requirements might be met by several protein preservatives, an assessment of their suitability under field conditions when targeted for metaproteomic analyses is currently lacking. Here, we compared the protein preservation performance of flash freezing and the preservation solution RNAlater using the marine gutless oligochaete Olavius algarvensis and its symbiotic microbes as a test case. In addition, we evaluated long-term RNAlater storage after 1 day, 1 week, and 4 weeks at room temperature (22°C to 23°C). We evaluated protein preservation using one-dimensional liquid chromatography-tandem mass spectrometry. We found that RNAlater and flash freezing preserved proteins equally well in terms of total numbers of identified proteins and relative abundances of individual proteins, and none of the test time points was altered, compared to time zero. Moreover, we did not find biases against specific taxonomic groups or proteins with particular biochemical properties. Based on our metaproteomic data and the logistical requirements for field deployment, we recommend RNAlater for protein preservation of field-collected samples targeted for metaproteomic analyses. IMPORTANCE Metaproteomics, the large-scale identification and quantification of proteins from microbial communities, provide direct insights into the phenotypes of microorganisms on the molecular level. To ensure the integrity of the metaproteomic data, samples need to be preserved immediately after sampling to avoid changes in protein abundance patterns. In laboratory setups, samples for proteomic analyses are most commonly preserved by flash freezing; however, liquid nitrogen or dry ice is often unavailable at remote field locations, due to their hazardous nature and transport restrictions. Our study shows that RNAlater can serve as a low-hazard, easy-to-transport alternative to flash freezing for field preservation of samples for metaproteomic analyses. We show that RNAlater preserves the metaproteome equally well, compared to flash freezing, and protein abundance patterns remain stable during long-term storage for at least 4 weeks at room temperature.
Collapse
|
17
|
Hettiarachchige IK, Vander Jagt CJ, Mann RC, Sawbridge TI, Spangenberg GC, Guthridge KM. Global Changes in Asexual Epichloë Transcriptomes during the Early Stages, from Seed to Seedling, of Symbiotum Establishment. Microorganisms 2021; 9:microorganisms9050991. [PMID: 34064362 PMCID: PMC8147782 DOI: 10.3390/microorganisms9050991] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/30/2021] [Accepted: 04/30/2021] [Indexed: 11/16/2022] Open
Abstract
Asexual Epichloë fungi are strictly seed-transmitted endophytic symbionts of cool-season grasses and spend their entire life cycle within the host plant. Endophyte infection can confer protective benefits to its host through the production of bioprotective compounds. Inversely, plants provide nourishment and shelter to the resident endophyte in return. Current understanding of the changes in global gene expression of asexual Epichloë endophytes during the early stages of host-endophyte symbiotum is limited. A time-course study using a deep RNA-sequencing approach was performed at six stages of germination, using seeds infected with one of three endophyte strains belonging to different representative taxa. Analysis of the most abundantly expressed endophyte genes identified that most were predicted to have a role in stress and defence responses. The number of differentially expressed genes observed at early time points was greater than those detected at later time points, suggesting an active transcriptional reprogramming of endophytes at the onset of seed germination. Gene ontology enrichment analysis revealed dynamic changes in global gene expression consistent with the developmental processes of symbiotic relationships. Expression of pathway genes for biosynthesis of key secondary metabolites was studied comprehensively and fuzzy clustering identified some unique expression patterns. Furthermore, comparisons of the transcriptomes from three endophyte strains in planta identified genes unique to each strain, including genes predicted to be associated with secondary metabolism. Findings from this study highlight the importance of better understanding the unique properties of individual endophyte strains and will serve as an excellent resource for future studies of host-endophyte interactions.
Collapse
Affiliation(s)
- Inoka K. Hettiarachchige
- Agriculture Victoria, AgriBio, Centre for AgriBioscience, Bundoora, VIC 3083, Australia; (I.K.H.); (C.J.V.J.); (R.C.M.); (T.I.S.); (G.C.S.)
| | - Christy J. Vander Jagt
- Agriculture Victoria, AgriBio, Centre for AgriBioscience, Bundoora, VIC 3083, Australia; (I.K.H.); (C.J.V.J.); (R.C.M.); (T.I.S.); (G.C.S.)
| | - Ross C. Mann
- Agriculture Victoria, AgriBio, Centre for AgriBioscience, Bundoora, VIC 3083, Australia; (I.K.H.); (C.J.V.J.); (R.C.M.); (T.I.S.); (G.C.S.)
| | - Timothy I. Sawbridge
- Agriculture Victoria, AgriBio, Centre for AgriBioscience, Bundoora, VIC 3083, Australia; (I.K.H.); (C.J.V.J.); (R.C.M.); (T.I.S.); (G.C.S.)
- School of Applied Systems Biology, La Trobe University, Bundoora, VIC 3086, Australia
| | - German C. Spangenberg
- Agriculture Victoria, AgriBio, Centre for AgriBioscience, Bundoora, VIC 3083, Australia; (I.K.H.); (C.J.V.J.); (R.C.M.); (T.I.S.); (G.C.S.)
- School of Applied Systems Biology, La Trobe University, Bundoora, VIC 3086, Australia
| | - Kathryn M. Guthridge
- Agriculture Victoria, AgriBio, Centre for AgriBioscience, Bundoora, VIC 3083, Australia; (I.K.H.); (C.J.V.J.); (R.C.M.); (T.I.S.); (G.C.S.)
- Correspondence:
| |
Collapse
|
18
|
Matilla MA, Ortega Á, Krell T. The role of solute binding proteins in signal transduction. Comput Struct Biotechnol J 2021; 19:1786-1805. [PMID: 33897981 PMCID: PMC8050422 DOI: 10.1016/j.csbj.2021.03.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/22/2021] [Accepted: 03/22/2021] [Indexed: 12/13/2022] Open
Abstract
The solute binding proteins (SBPs) of prokaryotes are present in the extracytosolic space. Although their primary function is providing substrates to transporters, SBPs also stimulate different signaling proteins, including chemoreceptors, sensor kinases, diguanylate cyclases/phosphodiesterases and Ser/Thr kinases, thereby causing a wide range of responses. While relatively few such systems have been identified, several pieces of evidence suggest that SBP-mediated receptor activation is a widespread mechanism. (1) These systems have been identified in Gram-positive and Gram-negative bacteria and archaea. (2) There is a structural diversity in the receptor domains that bind SBPs. (3) SBPs belonging to thirteen different families interact with receptor ligand binding domains (LBDs). (4) For the two most abundant receptor LBD families, dCache and four-helix-bundle, there are different modes of interaction with SBPs. (5) SBP-stimulated receptors carry out many different functions. The advantage of SBP-mediated receptor stimulation is attributed to a strict control of SBP levels, which allows a precise adjustment of the systeḿs sensitivity. We have compiled information on the effect of ligands on the transcript/protein levels of their cognate SBPs. In 87 % of the cases analysed, ligands altered SBP expression levels. The nature of the regulatory effect depended on the ligand family. Whereas inorganic ligands typically downregulate SBP expression, an upregulation was observed in response to most sugars and organic acids. A major unknown is the role that SBPs play in signaling and in receptor stimulation. This review attempts to summarize what is known and to present new information to narrow this gap in knowledge.
Collapse
Affiliation(s)
- Miguel A Matilla
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, Granada 18008, Spain
| | - Álvaro Ortega
- Department of Biochemistry and Molecular Biology 'B' and Immunology, Faculty of Chemistry, University of Murcia, Regional Campus of International Excellence "Campus Mare Nostrum", Murcia, Spain
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, Granada 18008, Spain
| |
Collapse
|
19
|
Salmonella enterica Serovars Dublin and Enteritidis Comparative Proteomics Reveals Differential Expression of Proteins Involved in Stress Resistance, Virulence, and Anaerobic Metabolism. Infect Immun 2021; 89:IAI.00606-20. [PMID: 33361201 DOI: 10.1128/iai.00606-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 12/10/2020] [Indexed: 11/20/2022] Open
Abstract
The Enteritidis and Dublin serovars of Salmonella enterica are phylogenetically closely related yet differ significantly in host range and virulence. S Enteritidis is a broad-host-range serovar that commonly causes self-limited gastroenteritis in humans, whereas S Dublin is a cattle-adapted serovar that can infect humans, often resulting in invasive extraintestinal disease. The mechanism underlying the higher invasiveness of S Dublin remains undetermined. In this work, we quantitatively compared the proteomes of clinical isolates of each serovar grown under gut-mimicking conditions. Compared to S Enteritidis, the S Dublin proteome was enriched in proteins linked to response to several stress conditions, such as those encountered during host infection, as well as to virulence. The S Enteritidis proteome contained several proteins related to central anaerobic metabolism pathways that were undetected in S Dublin. In contrast to what has been observed in other extraintestinal serovars, most of the coding genes for these pathways are not degraded in S Dublin. Thus, we provide evidence that S Dublin metabolic functions may be much more affected than previously reported based on genomic studies. Single and double null mutants in stress response proteins Dps, YciF, and YgaU demonstrate their relevance to S Dublin invasiveness in a murine model of invasive salmonellosis. All in all, this work provides a basis for understanding interserovar differences in invasiveness and niche adaptation, underscoring the relevance of using proteomic approaches to complement genomic studies.
Collapse
|
20
|
Liang Z, Xu G, Shi J, Yu S, Lu Q, Liang D, Sun L, Wang S. Sludge digestibility and functionally active microorganisms in methanogenic sludge digesters revealed by E. coli-fed digestion and microbial source tracking. ENVIRONMENTAL RESEARCH 2021; 193:110539. [PMID: 33253703 DOI: 10.1016/j.envres.2020.110539] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/19/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
Methanogenic sludge digestion plays a pivotal role in attenuating and hygienizing the massively-produced waste activated sludge (WAS), which is predominantly composed of microbial cells and extracellular polymeric substances (EPS). The efficient sludge digestion requires a variety of functionally active microorganisms working together closely to convert sludge organic matter into biogas. Nonetheless, the digestion efficiency (or digestibility quantified as carbon removal efficiency) of major sludge constituents (i.e., microbial cells and EPS) and associated functionally active microorganisms in sludge digesters remain elusive. In this study, we identified the digestibility of sludge microbial cells and the associated functionally active microorganisms by using Escherichia coli (E. coli)-fed digestion and microbial source tracking. The average carbon removals in four digesters fed with fresh WAS (WAS-AD), thermal pretreated WAS (Thermal-WAS-AD), E. coli cells (E.coli-AD) and thermal pretreated E. coli cells (Thermal-E.coli-AD) were 30.6 ± 3.4%, 45.8 ± 2.9%, 69.0 ± 3.4% and 68.9 ± 4.6%, respectively. Compared to WAS-AD and Thermal-WAS-AD, the significantly higher carbon removals in E. coli-AD and Thermal-E. coli-AD suggested the remarkably higher digestibility of microbial cells than EPS, and releasing organic matter from EPS might be a rate-limiting step in sludge digestion. Functionally active microorganisms for microbial cell digestion predominantly included fermenters (e.g., Petrimonas and Lentimicrobium), syntrophic acetogens (e.g., Synergistaceae) and methanogens (e.g., Methanosaeta and Methanosarcina). Microbial source tracking estimation showed that the microbial cell-digesting populations accounted for 35.6 ± 9.1% and 70.3 ± 10.1% of total microbial communities in the WAS-AD and Thermal-WAS-AD, respectively. Accordingly, the functionally active microorganisms for digestion of both microbial cells and EPS accounted for 64.5 ± 12.1% and 97.3 ± 2.0% of total digestion sludge microbiome in WAS-AD and Thermal-WAS-AD, respectively. By contrast, feeding WAS-derived microorganisms accounted for 23.2 ± 4.4% and 2.3 ± 1.2% of total microbial communities in the WAS-AD and Thermal-WAS-AD, respectively.
Collapse
Affiliation(s)
- Zhiwei Liang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Guofang Xu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Jiangjian Shi
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Sining Yu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Qihong Lu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Dawei Liang
- Beijing Key Laboratory of Bio-inspired Energy Materials and Devices, School of Space & Environment, Beihang University, Beijing, 100191, China
| | - Lianpeng Sun
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China
| | - Shanquan Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510275, China.
| |
Collapse
|
21
|
Taxonomic and Functional Shifts in the Sprout Spent Irrigation Water Microbiome in Response to Salmonella Contamination of Alfalfa Seeds. Appl Environ Microbiol 2021; 87:AEM.01811-20. [PMID: 33218999 DOI: 10.1128/aem.01811-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 11/11/2020] [Indexed: 11/20/2022] Open
Abstract
Despite recent advances in Salmonella-sprout research, little is known about the relationship between Salmonella and the sprout microbiome during sprouting. Sprout spent irrigation water (SSIW) provides an informative representation of the total microbiome of this primarily aquaponic crop. This study was designed to characterize the function and taxonomy of the most actively transcribed genes in SSIW from Salmonella enterica serovar Cubana-contaminated alfalfa seeds throughout the sprouting process. Genomic DNA and total RNA from SSIW was collected at regular intervals and sequenced using Illumina MiSeq and NextSeq platforms. Nucleic acid data were annotated using four different pipelines. Both metagenomic and metatranscriptomic analyses revealed a diverse and highly dynamic SSIW microbiome. A "core" SSIW microbiome comprised Klebsiella, Enterobacter, Pantoea, and Cronobacter The impact, however, of Salmonella contamination on alfalfa seeds influenced SSIW microbial community dynamics not only structurally but also functionally. Changes in genes associated with metabolism, genetic information processing, environmental information processing, and cellular processes were abundant and time dependent. At time points of 24 h, 48 h, and 96 h, totals of 541, 723, and 424 S Cubana genes, respectively, were transcribed at either higher or lower levels than at 0 h in SSIW during sprouting. An array of S Cubana genes (107) were induced at all three time points, including genes involved in biofilm formation and modulation, stress responses, and virulence and tolerance to antimicrobials. Taken together, these findings expand our understanding of the effect of Salmonella seed contamination on the sprout crop microbiome and metabolome.IMPORTANCE Interactions of human enteric pathogens like Salmonella with plants and plant microbiomes remain to be elucidated. The rapid development of next-generation sequencing technologies provides powerful tools enabling investigation of such interactions from broader and deeper perspectives. Using metagenomic and metatranscriptomic approaches, this study identified not only changes in microbiome structure of SSIW associated with sprouting but also changes in the gene expression patterns related to the sprouting process in response to Salmonella contamination of alfalfa seeds. This study advances our knowledge on Salmonella-plant (i.e., sprout) interaction.
Collapse
|
22
|
Bryant JA, Morris FC, Knowles TJ, Maderbocus R, Heinz E, Boelter G, Alodaini D, Colyer A, Wotherspoon PJ, Staunton KA, Jeeves M, Browning DF, Sevastsyanovich YR, Wells TJ, Rossiter AE, Bavro VN, Sridhar P, Ward DG, Chong ZS, Goodall EC, Icke C, Teo AC, Chng SS, Roper DI, Lithgow T, Cunningham AF, Banzhaf M, Overduin M, Henderson IR. Structure of dual BON-domain protein DolP identifies phospholipid binding as a new mechanism for protein localisation. eLife 2020; 9:62614. [PMID: 33315009 PMCID: PMC7806268 DOI: 10.7554/elife.62614] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 12/11/2020] [Indexed: 12/16/2022] Open
Abstract
The Gram-negative outer-membrane envelops the bacterium and functions as a permeability barrier against antibiotics, detergents, and environmental stresses. Some virulence factors serve to maintain the integrity of the outer membrane, including DolP (formerly YraP) a protein of unresolved structure and function. Here, we reveal DolP is a lipoprotein functionally conserved amongst Gram-negative bacteria and that loss of DolP increases membrane fluidity. We present the NMR solution structure for Escherichia coli DolP, which is composed of two BON domains that form an interconnected opposing pair. The C-terminal BON domain binds anionic phospholipids through an extensive membrane:protein interface. This interaction is essential for DolP function and is required for sub-cellular localisation of the protein to the cell division site, providing evidence of subcellular localisation of these phospholipids within the outer membrane. The structure of DolP provides a new target for developing therapies that disrupt the integrity of the bacterial cell envelope.
Collapse
Affiliation(s)
- Jack Alfred Bryant
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Faye C Morris
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Timothy J Knowles
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom.,School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
| | - Riyaz Maderbocus
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom.,Institute for Cancer and Genomic Sciences, University of Birmingham, Edgbaston, United Kingdom
| | - Eva Heinz
- Infection & Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
| | - Gabriela Boelter
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Dema Alodaini
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Adam Colyer
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Peter J Wotherspoon
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Kara A Staunton
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Mark Jeeves
- Institute for Cancer and Genomic Sciences, University of Birmingham, Edgbaston, United Kingdom
| | - Douglas F Browning
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | | | - Timothy J Wells
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Amanda E Rossiter
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Vassiliy N Bavro
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Pooja Sridhar
- School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
| | - Douglas G Ward
- School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
| | - Zhi-Soon Chong
- Department of Chemistry, National University of Singapore, Singapore, Singapore
| | - Emily Ca Goodall
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom.,Institute for Molecular Bioscience, University of Queensland, St. Lucia, Australia
| | - Christopher Icke
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom.,Institute for Molecular Bioscience, University of Queensland, St. Lucia, Australia
| | - Alvin Ck Teo
- School of Life Sciences, The University of Warwick, Coventry, United Kingdom
| | - Shu-Sin Chng
- Department of Chemistry, National University of Singapore, Singapore, Singapore.,School of Life Sciences, The University of Warwick, Coventry, United Kingdom
| | - David I Roper
- School of Life Sciences, The University of Warwick, Coventry, United Kingdom
| | - Trevor Lithgow
- Infection & Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Australia
| | - Adam F Cunningham
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom.,Institute of Inflammation and Immunotherapy, University of Birmingham, Edgbaston, United Kingdom
| | - Manuel Banzhaf
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom
| | - Michael Overduin
- School of Biosciences, University of Birmingham, Edgbaston, United Kingdom.,Department of Biochemistry, University of Alberta, Edmonton, Canada
| | - Ian R Henderson
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, United Kingdom.,Department of Chemistry, National University of Singapore, Singapore, Singapore
| |
Collapse
|
23
|
Yang G, Li B, Jia L, Qiu H, Yang M, Zhu B, Xie J, Qiu S, Li P, Ma H, Song H, Wang L. A Novel sRNA in Shigella flexneri That Regulates Tolerance and Virulence Under Hyperosmotic Pressure. Front Cell Infect Microbiol 2020; 10:483. [PMID: 33042862 PMCID: PMC7526569 DOI: 10.3389/fcimb.2020.00483] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 08/04/2020] [Indexed: 01/09/2023] Open
Abstract
Regulation of the environmental stress response and virulence of Shigella flexneri may involve multiple signaling pathways; however, these mechanisms are not well-defined. In bacteria, small regulatory RNAs (sRNAs) regulate bacterial growth, metabolism, virulence, and environmental stress response. Therefore, identifying novel functional sRNAs in S. flexneri could help elucidate pathogenic adaptations to host micro-environmental stresses and associated virulence. The aim of this study was to confirm the presence of an sRNA, Ssr54, in S. flexneri and to determine its functions and possible mechanism of action. Ssr54 was found to regulate tolerance and virulence under hyperosmotic pressure. Its expression was verified by qRT-PCR and Northern blotting, and its genomic position was confirmed by 5'-rapid amplification of cDNA ends. Ssr54 expression was significantly decreased (~ 80%) under hyperosmotic conditions (680 mM NaCl), and the survival rate of the Ssr54 deletion strain increased by 20% under these conditions. This suggested that Ssr54 has been selected to promote host survival under hyperosmotic conditions. Additionally, virulence assessment, including guinea pig Sereny test and competitive invasion assays in mouse lungs, revealed that Ssr54 deletion significantly decreased S. flexneri virulence. Two-dimensional gel analyses suggest that Ssr54 may modulate the expression of tolC, ompA, and treF genes, which may affect the virulence and survival of S. flexneri under osmotic pressures. Furthermore, treF expression has been shown to improve the survival of S. flexneri under osmotic pressures. These results suggest that Ssr54 has a broad range of action in S. flexneri response to hyperosmotic environmental stresses and in controlling its virulence to adapt to environmental stresses encountered during host infection.
Collapse
Affiliation(s)
- Guang Yang
- Center for Disease Control and Prevention of Chinese People's Liberation Army, Beijing, China
- The 5th Medical Center of General Hospital of Chinese People's Liberation Army, Beijing, China
| | - Boan Li
- The 5th Medical Center of General Hospital of Chinese People's Liberation Army, Beijing, China
| | - Leili Jia
- Center for Disease Control and Prevention of Chinese People's Liberation Army, Beijing, China
| | - Huaiyu Qiu
- Department of Ophthalmology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Mingjuan Yang
- Center for Disease Control and Prevention of Chinese People's Liberation Army, Beijing, China
| | | | - Jing Xie
- Center for Disease Control and Prevention of Chinese People's Liberation Army, Beijing, China
| | - Shaofu Qiu
- Center for Disease Control and Prevention of Chinese People's Liberation Army, Beijing, China
| | - Peng Li
- Center for Disease Control and Prevention of Chinese People's Liberation Army, Beijing, China
| | - Hui Ma
- The 6th Medical Center of General Hospital of Chinese People's Liberation Army, Beijing, China
| | - Hongbin Song
- Center for Disease Control and Prevention of Chinese People's Liberation Army, Beijing, China
| | - Ligui Wang
- Center for Disease Control and Prevention of Chinese People's Liberation Army, Beijing, China
| |
Collapse
|
24
|
Abstract
For bacteria, maintaining higher internal solute concentrations than those present in the environment allows cells to take up water. As a result, survival is challenging in high-osmolarity environments. To investigate how bacteria adapt to high-osmolarity environments, we maintained Escherichia coli in a variety of high-osmolarity solutions for hundreds of generations. We found that the evolved populations adopted different strategies to improve their growth rates depending on the osmotic passaging condition, either generally adapting to high-osmolarity conditions or better metabolizing the osmolyte as a carbon source. Single-cell imaging demonstrated that enhanced fitness was coupled to faster growth, and metagenomic sequencing revealed mutations that reflected growth trade-offs across osmolarities. Our study demonstrated the utility of long-term evolution experiments for probing adaptation occurring during environmental stress. Bacteria must maintain a cytosolic osmolarity higher than that of their environment in order to take up water. High-osmolarity environments therefore present formidable stress to bacteria. To explore the evolutionary mechanisms by which bacteria adapt to high-osmolarity environments, we selected Escherichia coli in media with a variety of osmolytes and concentrations for 250 generations. Adaptation was osmolyte dependent, with sorbitol stress generally resulting in increased fitness under conditions with higher osmolarity, while selection in high concentrations of proline resulted in increased fitness specifically on proline. Consistent with these phenotypes, sequencing of the evolved populations showed that passaging in proline resulted in specific mutations in an associated metabolic pathway that increased the ability to utilize proline for growth, while evolution in sorbitol resulted in mutations in many different genes that generally resulted in improved growth under high-osmolarity conditions at the expense of growth at low osmolarity. High osmolarity decreased the growth rate but increased the mean cell volume compared with growth on proline as the sole carbon source, demonstrating that osmolarity-induced changes in growth rate and cell size follow an orthogonal relationship from the classical Growth Law relating cell size and nutrient quality. Isolates from a sorbitol-evolved population that captured the likely temporal sequence of mutations revealed by metagenomic sequencing demonstrated a trade-off between growth at high osmolarity and growth at low osmolarity. Our report highlights the utility of experimental evolution for dissecting complex cellular networks and environmental interactions, particularly in the case of behaviors that can involve both specific and general metabolic stressors.
Collapse
|
25
|
Barcarolo MV, Gottig N, Ottado J, Garavaglia BS. Participation of two general stress response proteins from Xanthomonas citri subsp. citri in environmental stress adaptation and virulence. FEMS Microbiol Ecol 2020; 96:5868764. [PMID: 32639549 DOI: 10.1093/femsec/fiaa138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 07/06/2020] [Indexed: 11/14/2022] Open
Abstract
Xanthomonas citri subsp. citri (Xcc) is the bacteria responsible for citrus canker. During its life cycle Xcc is found on leaves as epiphyte, where desiccation conditions may occur. In this work, two Xcc genes, XAC0100 and XAC4007, predicted in silico to be involved in general stress response, were studied under salt, osmotic, desiccation, oxidative and freezing stress, and during plant-pathogen interaction. Expression of XAC0100 and XAC4007 genes was induced under these stress conditions. Disruption of both genes in Xcc caused decreased bacterial culturability under desiccation, freezing, osmotic and oxidative stress. Importantly, the lack of these genes impaired Xcc epiphytic fitness. Both Xac0100 and Xac4007 recombinant proteins showed protective effects on Xanthomonas cells subjected to drought stress. Also, Escherichia coli overexpressing Xac4007 showed a better performance under standard culture, saline and osmotic stress and were more tolerant to freezing and oxidative stress than wild type E. coli. Moreover, both Xac0100 and Xac4007 recombinant proteins were able to prevent the freeze-thaw-induced inactivation of L-Lactate dehydrogenase. In conclusion, Xac0100 and Xac4007 have a relevant role as bacteria and protein protectors; and these proteins are crucial to bacterial pathogens that must face environmental stressful conditions that compromise the accomplishment of the complete virulence process.
Collapse
Affiliation(s)
- María Victoria Barcarolo
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda, Rosario 2000, Argentina
| | - Natalia Gottig
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda, Rosario 2000, Argentina
| | - Jorgelina Ottado
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda, Rosario 2000, Argentina
| | - Betiana S Garavaglia
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda, Rosario 2000, Argentina
| |
Collapse
|
26
|
Zhang X, Nakaura Y, Zhu J, Zhang Z, Yamamoto K. Effect of Hyperosmotic Salt Concentration and Temperature on Viability of Escherichia coli during Cold Storage. Biocontrol Sci 2020; 25:55-62. [PMID: 32507791 DOI: 10.4265/bio.25.55] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Escherichia coli cells were suspended in phosphate-buffered saline solutions (pH 7.4) at physiological (0.9 %) and hyperosmotic (3.5, 5.0, and 10.0 %) concentrations of sodium chloride (NaCl) and stored at 5, 10, 15, 20, and 25 °C up to 48 d. During storage at 5 and 10 °C, viable cell counts decreased approximately from 9 log CFU/ml to 6-7 log CFU/ml, and NaCl showed slight protective effect on the decrease. When stored at 15, 20, and 25 °C, the counts decreased with increases in NaCl concentration and/or storage temperature. The cells in 10.0 % NaCl suspension became nondetectable after storage at 25 °C for 28 d. Under some storage conditions (NaCl ≤ 5 %, 20 and 25 °C), the counts approached constant values, indicating possible adaptation to NaCl. Injured cells were observed at 5.0 and 10.0 % NaCl. However, recovery was observed only at 5.0 % NaCl during storage at 20 °C. In addition, more cells were detected on nonselective medium when incubated at 37 °C than at 25 °C. Higher hyperosmotic NaCl solutions at higher storage temperatures reduced more viable cells of E. coli.
Collapse
Affiliation(s)
- Xue Zhang
- Graduate School of Life and Environmental Sciences, University of Tsukuba.,Food Research Institute, National Agriculture and Food Research Organization
| | - Yoshiko Nakaura
- Food Research Institute, National Agriculture and Food Research Organization
| | - Junzhang Zhu
- Graduate School of Life and Environmental Sciences, University of Tsukuba.,Food Research Institute, National Agriculture and Food Research Organization
| | - Zhenya Zhang
- Graduate School of Life and Environmental Sciences, University of Tsukuba
| | - Kazutaka Yamamoto
- Food Research Institute, National Agriculture and Food Research Organization
| |
Collapse
|
27
|
Wang X, Tang D, Wang W. Adaptation strategies of
Pseudomonas protegens
SN15‐2 to hyperosmotic growth environment. J Appl Microbiol 2020; 128:1720-1734. [DOI: 10.1111/jam.14582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/02/2020] [Accepted: 01/12/2020] [Indexed: 12/12/2022]
Affiliation(s)
- X. Wang
- State Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shanghai China
| | - D. Tang
- State Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shanghai China
| | - W. Wang
- State Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shanghai China
| |
Collapse
|
28
|
Improved tolerance of Escherichia coli to oxidative stress by expressing putative response regulator homologs from Antarctic bacteria. J Microbiol 2019; 58:131-141. [PMID: 31872373 DOI: 10.1007/s12275-020-9290-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 11/01/2019] [Accepted: 11/13/2019] [Indexed: 12/14/2022]
Abstract
Response regulator (RR) is known a protein that mediates cell's response to environmental changes. The effect of RR from extremophiles was still under investigation. In this study, response regulator homologs were mined from NGS data of Antarctic bacteria and overexpressed in Escherichia coli. Sixteen amino acid sequences were annotated corresponding to response regulators related to the two-component regulatory systems; of these, 3 amino acid sequences (DRH632, DRH1601 and DRH577) with high homology were selected. These genes were cloned in pRadGro and expressed in E. coli. The transformant strains were subjected to various abiotic stresses including oxidative, osmotic, thermal stress, and acidic stress. There was found that the robustness of E. coli to abiotic stress was increased in the presence of these response regulator homologs. Especially, recombinant E. coli overexpressing drh632 had the highest survival rate in oxidative, hypothermic, osmotic, and acidic conditions. Recombinant E. coli overexpressing drh1601 showed the highest tolerance level to osmotic stress. These results will be applicable for development of recombinant strains with high tolerance to abiotic stress.
Collapse
|
29
|
Yang B, Song H, An D, Zhang D, Raza SHA, Wang G, Shan X, Qian A, Kang Y, Wang C. Functional Analysis of preA in Aeromonas veronii TH0426 Reveals a Key Role in the Regulation of Virulence and Resistance to Oxidative Stress. Int J Mol Sci 2019; 21:ijms21010098. [PMID: 31877791 PMCID: PMC6981600 DOI: 10.3390/ijms21010098] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/14/2019] [Accepted: 12/18/2019] [Indexed: 01/12/2023] Open
Abstract
Aeromonas veronii is one of the main pathogens causing freshwater fish sepsis and ulcer syndrome. This bacterium has caused serious economic losses in the aquaculture industry worldwide, and it has become an important zoonotic and aquatic agent. However, little is known about the molecular mechanism of pathogenesis of A. veronii. In this study, we first constructed an unmarked mutant strain (ΔpreA) by generating an in-frame deletion of the preA gene, which encodes a periplasmic binding protein, to investigate its role in A. veronii TH0426. Our results showed that the motility and biofilm formation ability of ΔpreA were similar to those of the wild-type strain. However, the adhesion and invasion ability in epithelioma papulosum cyprini (EPC) cells were significantly enhanced (2.0-fold). Furthermore, the median lethal dose (LD50) of ΔpreA was 7.6-fold higher than that of the wild-type strain, which illustrates that the virulence of the mutant was significantly enhanced. This finding is also supported by the cytotoxicity test results, which showed that the toxicity of ΔpreA to EPC cells was enhanced 1.3-fold relative to the wild type. Conversely, tolerance test results showed that oxidative stress resistance of ΔpreA decreased 5.9-fold compared to with the wild-type strain. The results suggest that preA may negatively regulate the virulence of A. veronii TH0426 through the regulation of resistance to oxidative stress. These insights will help to further elucidate the function of preA and understand the pathogenesis of A. veronii.
Collapse
Affiliation(s)
- Bintong Yang
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
- College of Life Science, Changchun Sci-Tech University, Shuangyang District, Changchun 130600, China
| | - Haichao Song
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
| | - Dingjie An
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
| | - Dongxing Zhang
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
| | | | - Guiqin Wang
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
| | - Xiaofeng Shan
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
| | - Aidong Qian
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
| | - Yuanhuan Kang
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
- Correspondence: (Y.K.); (C.W.); Tel.: +86-0431-84533426 (Y.K. & C.W.)
| | - Chunfeng Wang
- College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (B.Y.); (H.S.); (D.A.); (D.Z.); (G.W.); (X.S.); (A.Q.)
- Correspondence: (Y.K.); (C.W.); Tel.: +86-0431-84533426 (Y.K. & C.W.)
| |
Collapse
|
30
|
Evaluation of adaptive response in E. coli O157:H7 to UV light and gallic acid based antimicrobial treatments. Food Control 2019. [DOI: 10.1016/j.foodcont.2019.106723] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
31
|
Xiong W, Luo W, Zhang X, Pan X, Zeng X, Yao C, Jing K, Shen L, Chen C, Ling X, Lu Y. High expression of toxic
Streptomyces
phospholipase D in
Escherichia coli
under salt stress and its mechanism. AIChE J 2019. [DOI: 10.1002/aic.16856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Weide Xiong
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
| | - Weiyi Luo
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
| | - Xueliang Zhang
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
| | - Xueshan Pan
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
| | - Xianhai Zeng
- College of EnergyXiamen University Xiamen People's Republic of China
| | - Chuanyi Yao
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
| | - Keju Jing
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
| | - Liang Shen
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
| | - Cuixue Chen
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
| | - Xueping Ling
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
- The Key Lab for Synthetic Biotechnology of Xiamen CityXiamen University Xiamen People's Republic of China
| | - Yinghua Lu
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical EngineeringXiamen University Xiamen People's Republic of China
- The Key Lab for Synthetic Biotechnology of Xiamen CityXiamen University Xiamen People's Republic of China
- Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological ResourcesXiamen University Xiamen People's Republic of China
| |
Collapse
|
32
|
Sun Z, Cagliero C, Izard J, Chen Y, Zhou YN, Heinz WF, Schneider TD, Jin DJ. Density of σ70 promoter-like sites in the intergenic regions dictates the redistribution of RNA polymerase during osmotic stress in Escherichia coli. Nucleic Acids Res 2019; 47:3970-3985. [PMID: 30843055 DOI: 10.1093/nar/gkz159] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 02/26/2019] [Accepted: 03/01/2019] [Indexed: 11/14/2022] Open
Abstract
RNA polymerase (RNAP), the transcription machinery, shows dynamic binding across the genomic DNA under different growth conditions. The genomic features that selectively redistribute the limited RNAP molecules to dictate genome-wide transcription in response to environmental cues remain largely unknown. We chose the bacterial osmotic stress response model to determine genomic features that direct genome-wide redistribution of RNAP during the stress. Genomic mapping of RNAP and transcriptome profiles corresponding to the different temporal states after salt shock were determined. We found rapid redistribution of RNAP across the genome, primarily at σ70 promoters. Three subsets of genes exhibiting differential salt sensitivities were identified. Sequence analysis using an information-theory based σ70 model indicates that the intergenic regions of salt-responsive genes are enriched with a higher density of σ70 promoter-like sites than those of salt-sensitive genes. In addition, the density of promoter-like sites has a positive linear correlation with RNAP binding at different salt concentrations. The RNAP binding contributed by the non-initiating promoter-like sites is important for gene transcription at high salt concentration. Our study demonstrates that hyperdensity of σ70 promoter-like sites in the intergenic regions of salt-responsive genes drives the RNAP redistribution for reprograming the transcriptome to counter osmotic stress.
Collapse
Affiliation(s)
- Zhe Sun
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Cedric Cagliero
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Jerome Izard
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Yixiong Chen
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Yan Ning Zhou
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - William F Heinz
- Optical Microscopy and Analysis Laboratory, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, MD 21702, USA
| | - Thomas D Schneider
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Ding Jun Jin
- RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| |
Collapse
|
33
|
Chiok KLR, Shah DH. Identification of common highly expressed genes of Salmonella Enteritidis by in silico prediction of gene expression and in vitro transcriptomic analysis. Poult Sci 2019; 98:2948-2963. [PMID: 30953073 DOI: 10.3382/ps/pez119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 02/27/2019] [Indexed: 01/02/2023] Open
Abstract
Chickens are the reservoir host of Salmonella Enteritidis. Salmonella Enteritidis colonizes the gastro-intestinal tract of chickens and replicates within macrophages without causing clinically discernable illness. Persistence of S. Enteritidis in the hostile environments of intestinal tract and macrophages allows it to disseminate extra-intestinally to liver, spleen, and reproductive tract. Extra-intestinal dissemination into reproductive tract leads to contamination of internal contents of eggs, which is a major risk factor for human infection. Understanding the genes that contribute to S. Enteritidis persistence in the chicken host is central to elucidate the genetic basis of the unique pathobiology of this public health pathogen. The aim of this study was to identify a succinct set of genes associated with infection-relevant in vitro environments to provide a rational foundation for subsequent biologically-relevant research. We used in silico prediction of gene expression and RNA-seq technology to identify a core set of 73 S. Enteritidis genes that are consistently highly expressed in multiple S. Enteritidis strains cultured at avian physiologic temperature under conditions that represent intestinal and intracellular environments. These common highly expressed (CHX) genes encode proteins involved in bacterial metabolism, protein synthesis, cell-envelope biogenesis, stress response, and a few proteins with uncharacterized functions. Further studies are needed to dissect the contribution of these CHX genes to the pathobiology of S. Enteritidis in the avian host. Several of the CHX genes could serve as promising targets for studies towards the development of immunoprophylactic and novel therapeutic strategies to prevent colonization of chickens and their environment with S. Enteritidis.
Collapse
Affiliation(s)
- Kim Lam R Chiok
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040
| | - Devendra H Shah
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040
| |
Collapse
|
34
|
Gao L, Ma X, Hu J, Zhang X, Chai T. Proteomic analysis of ESBL-producing Escherichia coli under bentonite condition. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:22305-22311. [PMID: 31154643 DOI: 10.1007/s11356-019-05429-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 05/08/2019] [Indexed: 06/09/2023]
Abstract
The dissemination of extended spectrum beta-lactamases (ESBL) genes through gene transfer attracts wide attention. Bentonite is widely used as a feed additive in an animal-breeding environment. In order to obtain a better understanding of the effect of bentonite on Escherichia coli carrying ESBL gene, proteomic analysis was carried out to screen the key proteins. The results showed that a total of 31 proteins were differentially expressed, including 21 up-regulated proteins and 10 down-regulated proteins. These proteins were involved in biosynthetic process, metabolic process, stress response, transport, anaerobic respiration, proteolysis, hydrolase, protein folding, transcription, salvage, and other. The transcriptional level of four genes (mipA, gntY, tldD, and arcA) was in consensus with proteomic results. This study revealed the differentially expressed proteins involved when E. coli was incubated under bentonite and PBS condition, which implied the possibility that bentonite may promote the transfer of ESBL gene between E. coli.
Collapse
Affiliation(s)
- Lili Gao
- Department of Microbiology, College of Basic Medicine, Zunyi Medical University, Huichuan District, Zunyi, 563003, Guizhou, China.
| | - Xiaochun Ma
- Department of Microbiology, College of Basic Medicine, Zunyi Medical University, Huichuan District, Zunyi, 563003, Guizhou, China
| | - Jiaqing Hu
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an, China
| | - Xiaodan Zhang
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an, China
| | - Tongjie Chai
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an, China.
| |
Collapse
|
35
|
Cui X, Hu C, Ou L, Kuramitsu Y, Masuda Y, Honjoh KI, Miyamoto T. Transcriptional analysis on heat resistance and recovery from thermal damage in Salmonella under high salt condition. Lebensm Wiss Technol 2019. [DOI: 10.1016/j.lwt.2019.02.056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
36
|
|
37
|
Zhu M, Dai X. Growth suppression by altered (p)ppGpp levels results from non-optimal resource allocation in Escherichia coli. Nucleic Acids Res 2019; 47:4684-4693. [PMID: 30916318 PMCID: PMC6511861 DOI: 10.1093/nar/gkz211] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 03/12/2019] [Accepted: 03/18/2019] [Indexed: 11/23/2022] Open
Abstract
Understanding how bacteria coordinate gene expression with biomass growth to adapt to various stress conditions remains a grand challenge in biology. Stress response is often associated with dramatic accumulation of cellular guanosine tetra- or penta-phosphate (p)ppGpp (also known as 'magic spot'), which is a key second messenger participating in regulating various biochemical and physiological processes of bacteria. Despite of the extensive studies on the mechanism of gene regulation by (p)ppGpp during stringent response, the connection between (p)ppGpp and bacterial steady-state exponential growth remains elusive. Here, we establish a versatile genetic approach to systematically perturb the (p)ppGpp level of Escherichia coli through titrating either the single-function (p)ppGpp synthetase or the singe-function (p)ppGpp hydrolase and quantitatively characterize cell growth and gene expression. Strikingly, increased and decreased (p)ppGpp levels both cause remarkable growth suppression of E. coli. From a coarse-grained insight, we demonstrate that increased (p)ppGpp levels limit ribosome synthesis while decreased (p)ppGpp levels limit the expression of metabolic proteins, both resulting in non-optimal resource allocation. Our study reveals a profound role of (p)ppGpp in regulating bacterial growth through governing global resource allocation. Moreover, we highlight the Mesh1 (p)ppGpp hydrolase from Drosophila melanogaster as a powerful genetic tool for interrogating bacterial (p)ppGpp physiology.
Collapse
Affiliation(s)
- Manlu Zhu
- School of life sciences, Central China Normal University, Wuhan, Hubei Province, China
| | - Xiongfeng Dai
- School of life sciences, Central China Normal University, Wuhan, Hubei Province, China
| |
Collapse
|
38
|
Quantitative microbial assessment for Escherichia coli after treatment by high voltage gas phase plasma. INNOV FOOD SCI EMERG 2019. [DOI: 10.1016/j.ifset.2018.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
39
|
A binding cooperativity switch driven by synergistic structural swelling of an osmo-regulatory protein pair. Nat Commun 2019; 10:1995. [PMID: 31040281 PMCID: PMC6491433 DOI: 10.1038/s41467-019-10002-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 04/12/2019] [Indexed: 02/07/2023] Open
Abstract
Uropathogenic E. coli experience a wide range of osmolarity conditions before and after successful infection. Stress-responsive regulatory proteins in bacteria, particularly proteins of the Hha family and H-NS, a transcription repressor, sense such osmolarity changes and regulate transcription through unknown mechanisms. Here we use an array of experimental probes complemented by molecular simulations to show that Cnu, a member of the Hha protein family, acts as an exquisite molecular sensor of solvent ionic strength. The osmosensory behavior of Cnu involves a fine-tuned modulation of disorder in the fourth helix and the three-dimensional structure in a graded manner. Order-disorder transitions in H-NS act synergistically with molecular swelling of Cnu contributing to a salt-driven switch in binding cooperativity. Thus, sensitivity to ambient conditions can be imprinted at the molecular level by tuning not just the degree of order in the protein conformational ensemble but also through population redistributions of higher-order molecular complexes. The bacterial protein Cnu together with the transcription repressor H-NS regulate expression of virulence factors in an osmo-sensitive manner. Here authors show that the structure of Cnu swells with decreasing ionic strength driving the oligomerization of H-NS and regulating osmo-sensory response.
Collapse
|
40
|
Deng CY, Zhang H, Wu Y, Ding LL, Pan Y, Sun ST, Li YJ, Wang L, Qian W. Proteolysis of histidine kinase VgrS inhibits its autophosphorylation and promotes osmostress resistance in Xanthomonas campestris. Nat Commun 2018; 9:4791. [PMID: 30442885 PMCID: PMC6237974 DOI: 10.1038/s41467-018-07228-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 10/18/2018] [Indexed: 11/16/2022] Open
Abstract
In bacterial cells, histidine kinases (HKs) are receptors that monitor environmental and intracellular stimuli. HKs and their cognate response regulators constitute two-component signalling systems (TCSs) that modulate cellular homeostasis through reversible protein phosphorylation. Here the authors show that the plant pathogen Xanthomonas campestris pv. campestris responds to osmostress conditions by regulating the activity of a HK (VgrS) via irreversible, proteolytic modification. This regulation is mediated by a periplasmic, PDZ-domain-containing protease (Prc) that cleaves the N-terminal sensor region of VgrS. Cleavage of VgrS inhibits its autokinase activity and regulates the ability of the cognate response regulator (VgrR) to bind promoters of downstream genes, thus promoting bacterial adaptation to osmostress. Bacterial histidine kinases (HKs) play key roles in the response to stimuli and are regulated by reversible phosphorylation. Here, the authors show that the activity of a HK in the plant pathogen Xanthomonas campestris is modulated by irreversible, proteolytic modification in response to osmostress.
Collapse
Affiliation(s)
- Chao-Ying Deng
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Huan Zhang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yao Wu
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Li-Li Ding
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yue Pan
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shu-Tao Sun
- Department of Core Facility, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ya-Jun Li
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,The College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Li Wang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Wei Qian
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
| |
Collapse
|
41
|
Lensmire JM, Pratt ZL, Wong ACL, Kaspar CW. Phosphate and carbohydrate facilitate the formation of filamentous Salmonella enterica during osmotic stress. MICROBIOLOGY-SGM 2018; 164:1503-1513. [PMID: 30325297 DOI: 10.1099/mic.0.000731] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Salmonella enterica is a human pathogen that can produce filamentous cells in response to environmental stress. The molecular mediators and biosynthetic pathways that contribute to the formation of filamentous cells (>10 µm in length) during osmotic stress are mostly unknown. The comparison of filamentous and non-filamentous cells in this study was aided by the use of a filtration step to separate cell types. Osmotic stress caused an efflux of phosphate from cells, and the addition of phosphate and a carbohydrate to Luria broth with 7 % NaCl (LB-7NaCl) significantly increased the proportion of filamentous cells in the population (58 %). In addition to direct measurements of intracellular and extracellular phosphate concentrations, the relative abundance of the iraP transcript that is induced by phosphate limitation was monitored. Non-filamentous cells had a greater relative abundance of iraP transcript than filamentous cells. IraP also affects the stability of RpoS, which regulates the general stress regulon, and was detected in non-filamentous cells but not filamentous cells. Markers of metabolic pathways for the production of acetyl-CoA (pflB, encoding for pyruvate formate lyase) and fatty acids (fabH) that are essential to membrane biosynthesis were found in greater abundance in filamentous cells than non-filamentous cells. There were no differences in the DNA, protein and biomass levels in filamentous and non-filamentous cells after 48 h of incubation, although the filamentous cells produced significantly (P<0.05) more acetate. This study found that phosphate and carbohydrate enhanced the formation of filamentous cells during osmotic stress, and there were differences in key regulatory elements and markers of metabolic pathways in filamentous and non-filamentous S. enterica.
Collapse
Affiliation(s)
- Joshua M Lensmire
- 1Department of Bacteriology, University of Wisconsin - Madison, Madison, WI, USA
| | | | - Amy C L Wong
- 1Department of Bacteriology, University of Wisconsin - Madison, Madison, WI, USA.,3Food Research Institute, University of Wisconsin - Madison, Madison, WI, USA
| | - Charles W Kaspar
- 3Food Research Institute, University of Wisconsin - Madison, Madison, WI, USA.,1Department of Bacteriology, University of Wisconsin - Madison, Madison, WI, USA
| |
Collapse
|
42
|
In Vivo Titration of Folate Pathway Enzymes. Appl Environ Microbiol 2018; 84:AEM.01139-18. [PMID: 30030232 DOI: 10.1128/aem.01139-18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 07/18/2018] [Indexed: 12/12/2022] Open
Abstract
How enzymes behave in cells is likely different from how they behave in the test tube. Previous in vitro studies find that osmolytes interact weakly with folate. Removal of the osmolyte from the solvation shell of folate is more difficult than removal of water, which weakens binding of folate to its enzyme partners. To examine if this phenomenon occurs in vivo, osmotic stress titrations were performed with Escherichia coli Two strategies were employed: resistance to an antibacterial drug and complementation of a knockout strain by the appropriate gene cloned into a plasmid that allows tight control of expression levels as well as labeling by a degradation tag. The abilities of the knockout and complemented strains to grow under osmotic stress were compared. Typically, the knockout strain could grow to high osmolalities on supplemented medium, while the complemented strain stopped growing at lower osmolalities on minimal medium. This pattern was observed for an R67 dihydrofolate reductase clone rescuing a ΔfolA strain, for a methylenetetrahydrofolate reductase clone rescuing a ΔmetF strain, and for a serine hydroxymethyltransferase clone rescuing a ΔglyA strain. Additionally, an R67 dihydrofolate reductase clone allowed E. coli DH5α to grow in the presence of trimethoprim until an osmolality of ∼0.81 is reached, while cells in a control titration lacking antibiotic could grow to 1.90 osmol.IMPORTANCEE. coli can survive in drought and flooding conditions and can tolerate large changes in osmolality. However, the cell processes that limit bacterial growth under high osmotic stress conditions are not known. In this study, the dose of four different enzymes in E. coli was decreased by using deletion strains complemented by the gene carried in a tunable plasmid. Under conditions of limiting enzyme concentration (lower than that achieved by chromosomal gene expression), cell growth can be blocked by osmotic stress conditions that are normally tolerated. These observations indicate that E. coli has evolved to deal with variations in its osmotic environment and that normal protein levels are sufficient to buffer the cell from environmental changes. Additional factors involved in the osmotic pressure response may include altered protein concentration/activity levels, weak solute interactions with ligands which can make it more difficult for proteins to bind their substrates/inhibitors/cofactors in vivo, and/or viscosity effects.
Collapse
|
43
|
Rani A, Babu S. Environmental proteomic studies: closer step to understand bacterial biofilms. World J Microbiol Biotechnol 2018; 34:120. [PMID: 30022302 DOI: 10.1007/s11274-018-2504-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 07/16/2018] [Indexed: 01/15/2023]
Abstract
Advancement in proteome analytical techniques and the development of protein databases have been helping to understand the physiology and subtle molecular mechanisms behind biofilm formation in bacteria. This review is to highlight how the evolving proteomic approaches have revealed fundamental molecular processes underlying the formation and regulation of bacterial biofilms. Based on the survey of research reports available on differential expression of proteins in biofilms of bacterial from wide range of environments, four important cellular processes viz. metabolism, motility, transport and stress response that contribute to formation of bacterial biofilms are discussed. This review might answer how proteins related to these cellular processes contribute significantly in stabilizing biofilms of different bacteria in diverse environmental conditions.
Collapse
Affiliation(s)
- Anupama Rani
- School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu, 632014, India
| | - Subramanian Babu
- School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu, 632014, India.
| |
Collapse
|
44
|
13-Docosenamide release by bacteria in response to glucose during growth-fluorescein quenching and clinical application. Appl Microbiol Biotechnol 2018; 102:6673-6685. [PMID: 29860593 DOI: 10.1007/s00253-018-9127-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 05/10/2018] [Accepted: 05/28/2018] [Indexed: 12/21/2022]
Abstract
Our investigations on extracellular biochemical events to find readily and sensitively detectable/measurable molecular targets for developing easier, simpler, and quicker diagnostic methods and tools for bacterial pathogens led to the observation that bacteria grown in the presence of glucose produced a compound capable of quenching fluorescein. Under the experimental conditions, among various sugars, glucose was found to induce maximum amount of the quencher when Escherichia coli was grown in presence of 50 mM glucose in rarified LB. The release of quencher closely following bacterial growth significantly from fourth hour after moderate inoculation. This fluorescein-quencher was purified using TLC and HPLC and identified using GC-MS as 13-docosenamide or erucamide, originally known as plant lipid, is a neuroactive compound in human and animals. Fluorescence and UV-absorption spectral analysis showed that the compound formed stable adduct with fluorescein in the ground state. Commercial 13-docosonamide enabled quantitation of the compound produced in micromolar quantities during glucose utilization from the medium. Twenty-seven different commonly encountered bacteria, pathogens or otherwise, could produce the quencher. A simple microplate-based growth monitoring method was developed exploiting quenching as an easily and readily measurable signal, either using a reader or an imager. While 13-docosenamide release by bacteria may be relevant in host-bacteria interactions, especially when growing under conditions that provide glucose, the new approach with inexpensive reagents can provide a new antibiogram technique.
Collapse
|
45
|
High Salt Cross-Protects Escherichia coli from Antibiotic Treatment through Increasing Efflux Pump Expression. mSphere 2018; 3:3/2/e00095-18. [PMID: 29643076 PMCID: PMC5909119 DOI: 10.1128/msphere.00095-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 03/24/2018] [Indexed: 02/02/2023] Open
Abstract
Environmental stresses often co-occur when bacteria confront antibiotic treatment. We provide a clear example that a natural stress condition (high salt) can cross-protect bacteria from antibiotic treatment by triggering the bacterial stress response program (elevated AcrAB-TolC efflux pump expression). Our study highlights the importance of taking the co-occurrence of bacterial environmental stresses into consideration when investigating antibiotic susceptibility and applying antimicrobial treatment. Environmental stresses often co-occur when bacteria encounter antibiotic treatment inside the human body. The cellular response to environmental stressors can alter the global gene expression pattern of bacteria. However, the relationship between the cellular stress response and antibiotic susceptibility remains poorly understood. Here we studied the effect of high salt, an important environmental stress condition inside the human body, on bacterial susceptibility to antibiotics. We found that high salt reduces the susceptibility of Escherichia coli to tetracycline and chloramphenicol, leading to a cross-protection effect. The cross-protection effect originates from the increased AcrAB-TolC efflux pump expression level under high-salt conditions. Our study demonstrates that stress-induced gene expression alterations can cross-protect bacteria from antibiotic treatment and should thus be considered when investigating antibiotic susceptibility and applying antimicrobial treatment. IMPORTANCE Environmental stresses often co-occur when bacteria confront antibiotic treatment. We provide a clear example that a natural stress condition (high salt) can cross-protect bacteria from antibiotic treatment by triggering the bacterial stress response program (elevated AcrAB-TolC efflux pump expression). Our study highlights the importance of taking the co-occurrence of bacterial environmental stresses into consideration when investigating antibiotic susceptibility and applying antimicrobial treatment.
Collapse
|
46
|
Calcines-Cruz C, Olvera A, Castro-Acosta RM, Zavala G, Alagón A, Trujillo-Roldán MA, Valdez-Cruz NA. Recombinant-phospholipase A2 production and architecture of inclusion bodies are affected by pH in Escherichia coli. Int J Biol Macromol 2018; 108:826-836. [DOI: 10.1016/j.ijbiomac.2017.10.178] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Revised: 10/30/2017] [Accepted: 10/30/2017] [Indexed: 12/20/2022]
|
47
|
Romantsov T, Gonzalez K, Sahtout N, Culham DE, Coumoundouros C, Garner J, Kerr CH, Chang L, Turner RJ, Wood JM. Cardiolipin synthase A colocalizes with cardiolipin and osmosensing transporter ProP at the poles of Escherichia coli cells. Mol Microbiol 2018; 107:623-638. [PMID: 29280215 DOI: 10.1111/mmi.13904] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 11/09/2017] [Accepted: 12/19/2017] [Indexed: 11/29/2022]
Abstract
Osmosensing by transporter ProP is modulated by its cardiolipin (CL)-dependent concentration at the poles of Escherichia coli cells. Other contributors to this phenomenon were sought with the BACterial Two-Hybrid System (BACTH). The BACTH-tagged variants T18-ProP and T25-ProP retained ProP function and localization. Their interaction confirmed the ProP homo-dimerization previously established by protein crosslinking. YdhP, YjbJ and ClsA were prominent among the putative ProP interactors identified by the BACTH system. The functions of YdhP and YjbJ are unknown, although YjbJ is an abundant, osmotically induced, soluble protein. ClsA (CL Synthase A) had been shown to determine ProP localization by mediating CL synthesis. Unlike a deletion of clsA, deletion of ydhP or yjbJ had no effect on ProP localization or function. All three proteins were concentrated at the cell poles, but only ClsA localization was CL-dependent. ClsA was shown to be N-terminally processed and membrane-anchored, with dual, cytoplasmic, catalytic domains. Active site amino acid replacements (H224A plus H404A) inactivated ClsA and compromised ProP localization. YdhP and YjbJ may be ClsA effectors, and interactions of YdhP, YjbJ and ClsA with ProP may reflect their colocalization at the cell poles. Targeted CL synthesis may contribute to the polar localization of CL, ClsA and ProP.
Collapse
Affiliation(s)
- Tatyana Romantsov
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Karen Gonzalez
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Naheda Sahtout
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Doreen E Culham
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Chelsea Coumoundouros
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Jennifer Garner
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Craig H Kerr
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Limei Chang
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, AB T2N 1N4, Canada
| | - Raymond J Turner
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, AB T2N 1N4, Canada
| | - Janet M Wood
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| |
Collapse
|
48
|
Fang KY, Lieblich SA, Tirrell DA. Incorporation of Non-Canonical Amino Acids into Proteins by Global Reassignment of Sense Codons. Methods Mol Biol 2018; 1798:173-186. [PMID: 29868959 DOI: 10.1007/978-1-4939-7893-9_13] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Non-canonical amino acids are finding increasing use in basic and applied research. Proteins that evolved naturally for biological function did so by exploiting the chemistries of the canonical amino acids; however, when proteins are repurposed for biomedical and pharmacological applications, they are often subject to conditions different from those characteristic of their original biological environments. Non-canonical amino acids can impart properties that are inaccessible within canonical protein sequence space, and can thereby lead to improved or new functionality. We describe simple methods for global replacement of canonical amino acids by their non-canonical counterparts in recombinant proteins made in high yield in bacterial expression hosts. These methods can be used to engineer both chemical and physical properties of recombinant proteins.
Collapse
Affiliation(s)
- Katharine Y Fang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Seth A Lieblich
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - David A Tirrell
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA.
| |
Collapse
|
49
|
Sarkar P, Switzer A, Peters C, Pogliano J, Wigneshweraraj S. Phenotypic consequences of RNA polymerase dysregulation in Escherichia coli. Nucleic Acids Res 2017; 45:11131-11143. [PMID: 28977482 PMCID: PMC5737641 DOI: 10.1093/nar/gkx733] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 08/09/2017] [Indexed: 01/25/2023] Open
Abstract
Many bacterial adaptive responses to changes in growth conditions due to biotic and abiotic factors involve reprogramming of gene expression at the transcription level. The bacterial RNA polymerase (RNAP), which catalyzes transcription, can thus be considered as the major mediator of cellular adaptive strategies. But how do bacteria respond if a stress factor directly compromises the activity of the RNAP? We used a phage-derived small protein to specifically perturb bacterial RNAP activity in exponentially growing Escherichia coli. Using cytological profiling, tracking RNAP behavior at single-molecule level and transcriptome analysis, we reveal that adaptation to conditions that directly perturb bacterial RNAP performance can result in a biphasic growth behavior and thereby confer the 'adapted' bacterial cells an enhanced ability to tolerate diverse antibacterial stresses. The results imply that while synthetic transcriptional rewiring may confer bacteria with the intended desirable properties, such approaches may also collaterally allow them to acquire undesirable traits.
Collapse
Affiliation(s)
- Paramita Sarkar
- MRC Centre for Molecular Bateriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Amy Switzer
- MRC Centre for Molecular Bateriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Christine Peters
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Joe Pogliano
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | | |
Collapse
|
50
|
Bae YM, Yoon JH, Kim JY, Lee SY. Identifying the mechanism ofEscherichia coliO157:H7 survival by the addition of salt in the treatment with organic acids. J Appl Microbiol 2017; 124:241-253. [DOI: 10.1111/jam.13613] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 07/30/2017] [Accepted: 08/03/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Y.-M. Bae
- Department of Food Science and Technology; Chung-Ang University; Anseong-si Gyeonggi-do Korea
| | - J.-H. Yoon
- Department of Food Science and Technology; Chung-Ang University; Anseong-si Gyeonggi-do Korea
| | - J.-Y. Kim
- Department of Food Science and Technology; Chung-Ang University; Anseong-si Gyeonggi-do Korea
| | - S.-Y. Lee
- Department of Food Science and Technology; Chung-Ang University; Anseong-si Gyeonggi-do Korea
| |
Collapse
|