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Peoples LM, Isanta-Navarro J, Bras B, Hand BK, Rosenzweig F, Elser JJ, Church MJ. Physiology, fast and slow: bacterial response to variable resource stoichiometry and dilution rate. mSystems 2024; 9:e0077024. [PMID: 38980051 PMCID: PMC11334502 DOI: 10.1128/msystems.00770-24] [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: 06/06/2024] [Accepted: 06/19/2024] [Indexed: 07/10/2024] Open
Abstract
Microorganisms grow despite imbalances in the availability of nutrients and energy. The biochemical and elemental adjustments that bacteria employ to sustain growth when these resources are suboptimal are not well understood. We assessed how Pseudomonas putida KT2440 adjusts its physiology at differing dilution rates (to approximate growth rates) in response to carbon (C), nitrogen (N), and phosphorus (P) stress using chemostats. Cellular elemental and biomolecular pools were variable in response to different limiting resources at a slow dilution rate of 0.12 h-1, but these pools were more similar across treatments at a faster rate of 0.48 h-1. At slow dilution rates, limitation by P and C appeared to alter cell growth efficiencies as reflected by changes in cellular C quotas and rates of oxygen consumption, both of which were highest under P- and lowest under C- stress. Underlying these phenotypic changes was differential gene expression of terminal oxidases used for ATP generation that allows for increased energy generation efficiency. In all treatments under fast dilution rates, KT2440 formed aggregates and biofilms, a physiological response that hindered an accurate assessment of growth rate, but which could serve as a mechanism that allows cells to remain in conditions where growth is favorable. Our findings highlight the ways that microorganisms dynamically adjust their physiology under different resource supply conditions, with distinct mechanisms depending on the limiting resource at slow growth and convergence toward an aggregative phenotype with similar compositions under conditions that attempt to force fast growth. IMPORTANCE All organisms experience suboptimal growth conditions due to low nutrient and energy availability. Their ability to survive and reproduce under such conditions determines their evolutionary fitness. By imposing suboptimal resource ratios under different dilution rates on the model organism Pseudomonas putida KT2440, we show that this bacterium dynamically adjusts its elemental composition, morphology, pools of biomolecules, and levels of gene expression. By examining the ability of bacteria to respond to C:N:P imbalance, we can begin to understand how stoichiometric flexibility manifests at the cellular level and impacts the flow of energy and elements through ecosystems.
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Affiliation(s)
- Logan M. Peoples
- Flathead Lake Biological Station, University of Montana, Polson, Montana, USA
| | - Jana Isanta-Navarro
- Flathead Lake Biological Station, University of Montana, Polson, Montana, USA
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Benedicta Bras
- Flathead Lake Biological Station, University of Montana, Polson, Montana, USA
| | - Brian K. Hand
- Flathead Lake Biological Station, University of Montana, Polson, Montana, USA
| | - Frank Rosenzweig
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - James J. Elser
- Flathead Lake Biological Station, University of Montana, Polson, Montana, USA
| | - Matthew J. Church
- Flathead Lake Biological Station, University of Montana, Polson, Montana, USA
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2
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Ezeduru V, Shao ARQ, Venegas FA, McKay G, Rich J, Nguyen D, Thibodeaux CJ. Defining the functional properties of cyclopropane fatty acid synthase from Pseudomonas aeruginosa PAO1. J Biol Chem 2024; 300:107618. [PMID: 39095026 PMCID: PMC11387697 DOI: 10.1016/j.jbc.2024.107618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Revised: 07/20/2024] [Accepted: 07/22/2024] [Indexed: 08/04/2024] Open
Abstract
Cyclopropane fatty acid synthases (CFAS) catalyze the conversion of unsaturated fatty acids to cyclopropane fatty acids (CFAs) within bacterial membranes. This modification alters the biophysical properties of membranes and has been correlated with virulence in several human pathogens. Despite the central role played by CFAS enzymes in regulating bacterial stress responses, the mechanistic properties of the CFAS enzyme family and the consequences of CFA biosynthesis remain largely uncharacterized in most bacteria. We report the first characterization of the CFAS enzyme from Pseudomonas aeruginosa (PA), an opportunistic human pathogen with complex membrane biology that is frequently associated with antimicrobial resistance and high tolerance to various external stressors. We demonstrate that CFAs are produced by a single enzyme in PA and that cfas gene expression is upregulated during the transition to stationary phase and in response to oxidative stress. Analysis of PA lipid extracts reveal a massive increase in CFA production as PA cells enter stationary phase and help define the optimal membrane composition for in vitro assays. The purified PA-CFAS enzyme forms a stable homodimer and preferentially modifies phosphatidylglycerol lipid substrates and membranes with a higher content of unsaturated acyl chains. Bioinformatic analysis across bacterial phyla shows highly divergent amino acid sequences within the lipid-binding domain of CFAS enzymes, perhaps suggesting distinct membrane-binding properties among different orthologs. This work lays an important foundation for further characterization of CFAS in P. aeruginosa and for examining the functional differences between CFAS enzymes from different bacteria.
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Affiliation(s)
- Vivian Ezeduru
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Annie R Q Shao
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Felipe A Venegas
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Geoffrey McKay
- Research Institute of the McGill University Health Center, McGill University, Montreal, Quebec, Canada
| | - Jacquelyn Rich
- Research Institute of the McGill University Health Center, McGill University, Montreal, Quebec, Canada; Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
| | - Dao Nguyen
- Research Institute of the McGill University Health Center, McGill University, Montreal, Quebec, Canada; Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Christopher J Thibodeaux
- Department of Chemistry, McGill University, Montreal, Quebec, Canada; Centre de Recherche en Biologie Structurale, McGill University, Montreal, Quebec, Canada.
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3
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Omar I, Crotti M, Li C, Pisak K, Czemerys B, Ferla S, van Noord A, Paul CE, Karu K, Ozbalci C, Eggert U, Lloyd R, Barry SM, Castagnolo D. Insights into E. coli Cyclopropane Fatty Acid Synthase (CFAS) Towards Enantioselective Carbene Free Biocatalytic Cyclopropanation. Angew Chem Int Ed Engl 2024; 63:e202403493. [PMID: 38662909 DOI: 10.1002/anie.202403493] [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: 02/19/2024] [Indexed: 06/16/2024]
Abstract
Cyclopropane fatty acid synthases (CFAS) are a class of S-adenosylmethionine (SAM) dependent methyltransferase enzymes able to catalyse the cyclopropanation of unsaturated phospholipids. Since CFAS enzymes employ SAM as a methylene source to cyclopropanate alkene substrates, they have the potential to be mild and more sustainable biocatalysts for cyclopropanation transformations than current carbene-based approaches. This work describes the characterisation of E. coli CFAS (ecCFAS) and its exploitation in the stereoselective biocatalytic synthesis of cyclopropyl lipids. ecCFAS was found to convert phosphatidylglycerol (PG) to methyl dihydrosterculate 1 with up to 58 % conversion and 73 % ee and the absolute configuration (9S,10R) was established. Substrate tolerance of ecCFAS was found to be correlated with the electronic properties of phospholipid headgroups and for the first time ecCFAS was found to catalyse cyclopropanation of both phospholipid chains to form dicyclopropanated products. In addition, mutagenesis and in silico experiments were carried out to identify the enzyme residues with key roles in catalysis and to provide structural insights into the lipid substrate preference of ecCFAS. Finally, the biocatalytic synthesis of methyl dihydrosterculate 1 and its deuterated analogue was also accomplished combining recombinant ecCFAS with the SAM regenerating AtHMT enzyme in the presence of CH3I and CD3I respectively.
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Affiliation(s)
- Iman Omar
- Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ, London, United Kingdom
- Department of Chemistry, Faculty of Natural, Mathematical and Engineering Sciences, King's College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
| | - Michele Crotti
- Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ, London, United Kingdom
- Department of Chemistry, Faculty of Natural, Mathematical and Engineering Sciences, King's College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
| | - Chuhan Li
- Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ, London, United Kingdom
| | - Krisztina Pisak
- Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ, London, United Kingdom
| | - Blazej Czemerys
- Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ, London, United Kingdom
- Department of Chemistry, Faculty of Natural, Mathematical and Engineering Sciences, King's College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
| | - Salvatore Ferla
- Medical School, Faculty of Medicine, Health and Life Science, Swansea University, Swansea, SA2 8PP
| | - Aster van Noord
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629HZ, Delft, The, Netherlands
| | - Caroline E Paul
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629HZ, Delft, The, Netherlands
| | - Kersti Karu
- Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ, London, United Kingdom
| | - Cagakan Ozbalci
- Department of Chemistry, Faculty of Natural, Mathematical and Engineering Sciences, King's College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
- Randall Centre for Cell and Molecular Biophysics, Faculty of Life Sciences and Medicine, King's College London, London, SE1 1UL, United Kingdom
| | - Ulrike Eggert
- Department of Chemistry, Faculty of Natural, Mathematical and Engineering Sciences, King's College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
- Randall Centre for Cell and Molecular Biophysics, Faculty of Life Sciences and Medicine, King's College London, London, SE1 1UL, United Kingdom
| | - Richard Lloyd
- DSD Chemistry, GSK Medicines Research Centre, Gunnels, Wood Road, Stevenage, SG1 2NY
| | - Sarah M Barry
- Department of Chemistry, Faculty of Natural, Mathematical and Engineering Sciences, King's College London, 7 Trinity Street, SE1 1DB, London, United Kingdom
| | - Daniele Castagnolo
- Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ, London, United Kingdom
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Rahn HP, Sun J, Li Z, Waymouth RM, Levy R, Wender PA. Isoprenoid CARTs: In Vitro and In Vivo mRNA Delivery by Charge-Altering Releasable Transporters Functionalized with Archaea-inspired Branched Lipids. Biomacromolecules 2024; 25:4305-4316. [PMID: 38814265 DOI: 10.1021/acs.biomac.4c00373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
The delivery of oligonucleotides across biological barriers is a challenge of unsurpassed significance at the interface of materials science and medicine, with emerging clinical utility in prophylactic and therapeutic vaccinations, immunotherapies, genome editing, and cell rejuvenation. Here, we address the role of readily available branched lipids in the design, synthesis, and evaluation of isoprenoid charge-altering releasable transporters (CARTs), a pH-responsive oligomeric nanoparticle delivery system for RNA. Systematic variation of the lipid block reveals an emergent relationship between the lipid block and the neutralization kinetics of the polycationic block. Unexpectedly, iA21A11, a CART with the smallest lipid side chain, isoamyl-, was identified as the lead isoprenoid CART for the in vitro transfection of immortalized lymphoblastic cell lines. When administered intramuscularly in a murine model, iA21A11-mRNA complexes induce higher protein expression levels than our previous lead CART, ONA. Isoprenoid CARTs represent a new delivery platform for RNA vaccines and other polyanion-based therapeutics.
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Affiliation(s)
- Harrison P Rahn
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Jiuzhi Sun
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Zhijian Li
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Robert M Waymouth
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Ronald Levy
- Stanford Cancer Institute, Division of Oncology, Department of Medicine, Stanford University, Stanford, California 94305, United States
| | - Paul A Wender
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
- Department of Chemical and Systems Biology, Stanford University, Stanford, California 94305, United States
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5
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Nsiah ST, Fabijanczuk KC, McLuckey SA. Structural characterization of fatty acid anions via gas-phase charge inversion using Mg(tri-butyl-terpyridine) 2 2+ reagent ions. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2024; 38:e9741. [PMID: 38567638 DOI: 10.1002/rcm.9741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 02/23/2024] [Accepted: 02/27/2024] [Indexed: 04/04/2024]
Abstract
RATIONALE Free fatty acids and lipid classes containing fatty acid esters are major components of lipidome. In the absence of a chemical derivatization step, FA anions do not yield all of the structural information that may be of interest under commonly used collision-induced dissociation (CID) conditions. A line of work that avoids condensed-phase derivatization takes advantage of gas-phase ion/ion chemistry to charge invert FA anions to an ion type that provides the structural information of interest using conventional CID. This work was motivated by the potential for significant improvement in overall efficiency for obtaining FA chain structural information. METHODS A hybrid triple quadrupole/linear ion-trap tandem mass spectrometer that has been modified to enable the execution of ion/ion reaction experiments was used to evaluate the use of 4,4',4″-tri-tert-butyl-2,2':6',2″-terpyridine (ttb-Terpy) as the ligand in divalent magnesium complexes for charge inversion of FA anions. RESULTS Mg(ttb-Terpy)2 2+ complexes provide significantly improved efficiency in producing structurally informative products from FA ions relative to Mg(Terpy)2 2+ complexes, as demonstrated for straight-chain FAs, branched-chain FAs, unsaturated FAs, and cyclopropane-containing FAs. It was discovered that most of the structurally informative fragmentation from [FA-H + Mg(ttb-Terpy)]+ results from the loss of a methyl radical from the ligand followed by radical-directed dissociation (RDD), which stands in contrast to the charge-remote fragmentation (CRF) believed to be operative with the [FA-H + Mg(Terpy)]+ ions. CONCLUSIONS This work demonstrates that a large fraction of product ions from the CID of ions of the form [FA-H + Mg(ttb-Terpy)]+ are derived from RDD of the FA backbone, with a very minor fraction arising from structurally uninformative dissociation channels. This ligand provides an alternative to previously used ligands for the structural characterization of FAs via CRF.
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Affiliation(s)
- Sarah T Nsiah
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
| | | | - Scott A McLuckey
- Department of Chemistry, Purdue University, West Lafayette, Indiana, USA
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6
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Yeboah J, Metott ZJ, Butch CM, Hillesheim PC, Mirjafari A. Are nature's strategies the solutions to the rational design of low-melting, lipophilic ionic liquids? Chem Commun (Camb) 2024; 60:3891-3909. [PMID: 38420843 PMCID: PMC10994746 DOI: 10.1039/d3cc06066g] [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] [Indexed: 03/02/2024]
Abstract
Ionic liquids (ILs) have emerged as a new class of materials, displaying a unique capability to self-assemble into micelles, liposomes, liquid crystals, and microemulsions. Despite evident interest, advancements in the controlled formation of amphiphilic ILs remain in the early stages. Taking inspiration from nature, we introduced the concept of lipid-like (or lipid-inspired) ILs more than a decade ago, aiming to create very low-melting, highly lipophilic ILs that are potentially bio-innocuous - a combination of attributes that is frequently antithetical but highly desirable from several application-specific standpoints. Lipid-like ILs are a subclass of functional organic liquid salts that include a range of lipidic side chains such as saturated, unsaturated, linear, branched, and thioether while retaining melting points below room temperature. It was observed in several homologous series of [Cnmim] ILs that elongation of N-appended alkyl chains to greater than seven carbons leads to a substantial increase in melting point (Tm) - which is the most characteristic feature of ILs. Accordingly, it is challenging to develop ILs with low Tm values while preserving their hydrophobicity and self-organizing properties. We found that two alternative Tm depressive approaches are useful. One of these is the replacement of the double bonds with thioether moieties in the alkyl chains, as detailed in several published papers detailing the chemistry of these ILs. Employing thiol-ene and thiol-yne click reactions is a facile, robust, and orthogonal method to overcome the challenges associated with the synthesis of alkyl thioether-functionalized ILs. The second approach involves replacing the double bonds with the cisoid cyclopropyl motif, mimicking the strategy used by certain organisms to modulate cell membrane fluidity. This discovery has the potential to greatly impact the utilization of lipid-like ILs in various applications, including gene delivery, lubricants, heat transfer fluids, and haloalkane separations, among others. This feature article presents a concise, historical overview, highlighting key findings from our work while offering speculation about the future trajectory of this de novo class of soft organic-ion materials.
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Affiliation(s)
- John Yeboah
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, USA.
| | - Zachary J Metott
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, USA.
| | - Christopher M Butch
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, USA.
| | - Patrick C Hillesheim
- Department of Chemistry and Physics, Ave Maria University, Ave Maria, Florida, 34142, USA.
| | - Arsalan Mirjafari
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, USA.
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Lee TH, Charchar P, Separovic F, Reid GE, Yarovsky I, Aguilar MI. The intricate link between membrane lipid structure and composition and membrane structural properties in bacterial membranes. Chem Sci 2024; 15:3408-3427. [PMID: 38455013 PMCID: PMC10915831 DOI: 10.1039/d3sc04523d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 01/26/2024] [Indexed: 03/09/2024] Open
Abstract
It is now evident that the cell manipulates lipid composition to regulate different processes such as membrane protein insertion, assembly and function. Moreover, changes in membrane structure and properties, lipid homeostasis during growth and differentiation with associated changes in cell size and shape, and responses to external stress have been related to drug resistance across mammalian species and a range of microorganisms. While it is well known that the biomembrane is a fluid self-assembled nanostructure, the link between the lipid components and the structural properties of the lipid bilayer are not well understood. This perspective aims to address this topic with a view to a more detailed understanding of the factors that regulate bilayer structure and flexibility. We describe a selection of recent studies that address the dynamic nature of bacterial lipid diversity and membrane properties in response to stress conditions. This emerging area has important implications for a broad range of cellular processes and may open new avenues of drug design for selective cell targeting.
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Affiliation(s)
- Tzong-Hsien Lee
- Department of Biochemistry and Molecular Biology, Monash University Clayton VIC 3800 Australia
| | - Patrick Charchar
- School of Engineering, RMIT University Melbourne Victoria 3001 Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne VIC 3010 Australia
| | - Gavin E Reid
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne VIC 3010 Australia
- Department of Biochemistry and Pharmacology, University of Melbourne Parkville VIC 3010 Australia
| | - Irene Yarovsky
- School of Engineering, RMIT University Melbourne Victoria 3001 Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology, Monash University Clayton VIC 3800 Australia
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8
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Yoon JH, Bae YM, Shin Y, Lee SY. Escherichia coli O157:H7 had a high degree of acid resistance in the presence of osmolytes (glycerol, glycine or fructose) by altering its lipid membrane composition. Food Microbiol 2024; 117:104388. [PMID: 37919012 DOI: 10.1016/j.fm.2023.104388] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 09/12/2023] [Accepted: 09/17/2023] [Indexed: 11/04/2023]
Abstract
This study aims to investigate the resistance of E. coli O157:H7 to acetic acid (AA) or malic acid (MA) by adding osmolytes, such as glycerol, glycine, glucose, and fructose, in Luria-Bertani broth without NaCl (LBW/S) or phosphate buffer (PB) stored at 25 °C. In LBW/S, a significantly (p < 0.05) higher D-value of E. coli O157:H7 was observed when treated with AA and 20% glycine (D-value: 1.18-3.44) or 40% glucose (D-value: 1.05-2.52) compared to that of AA alone (D-value: 0.40-0.47). In contrast, the addition of osmolytes (i.e. 3-40% glucose, 3-40% fructose or 20% glycine) to LBW/S acidified by MA significantly decreased D-values of E. coli O157:H7, which was enumerated by using a selective medium. Furthermore, when E. coli O157:H7 was incubated in LBW/S containing AA and osmolytes at 25 °C for 3 d, this bacterium had an increased proportion of C16:0 and C17:0 cyclo (cyclopropane acid) compared to its AA-treated counterparts. Along with the altered shift in membrane phospholipids, the addition of osmolytes into a laboratory medium in the presence of nutritive substrates may increase the resistance of E. coli O157:H7 to AA.
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Affiliation(s)
- Jae-Hyun Yoon
- Department of Food and Nutrition, Sunchon National University, 235 Jungang-ro, Suncheon-si, Jeollanam-do, 57922, Republic of Korea
| | - Young-Min Bae
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-dearo, Anseong-si, Gyeonggi-do, 17546, Republic of Korea
| | - Yooncheol Shin
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-dearo, Anseong-si, Gyeonggi-do, 17546, Republic of Korea
| | - Sun-Young Lee
- Department of Food and Nutrition, Chung-Ang University, 4726 Seodong-dearo, Anseong-si, Gyeonggi-do, 17546, Republic of Korea.
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9
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Rivera Vazquez J, Trujillo E, Williams J, She F, Getahun F, Callaghan MM, Coon JJ, Amador-Noguez D. Lipid membrane remodeling and metabolic response during isobutanol and ethanol exposure in Zymomonas mobilis. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:14. [PMID: 38281959 PMCID: PMC10823705 DOI: 10.1186/s13068-023-02450-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 12/16/2023] [Indexed: 01/30/2024]
Abstract
BACKGROUND Recent engineering efforts have targeted the ethanologenic bacterium Zymomonas mobilis for isobutanol production. However, significant hurdles remain due this organism's vulnerability to isobutanol toxicity, adversely affecting its growth and productivity. The limited understanding of the physiological impacts of isobutanol on Z. mobilis constrains our ability to overcome these production barriers. RESULTS We utilized a systems-level approach comprising LC-MS/MS-based lipidomics, metabolomics, and shotgun proteomics, to investigate how exposure to ethanol and isobutanol impact the lipid membrane composition and overall physiology of Z. mobilis. Our analysis revealed significant and distinct alterations in membrane phospholipid and fatty acid composition resulting from ethanol and isobutanol exposure. Notably, ethanol exposure increased membrane cyclopropane fatty acid content and expression of cyclopropane fatty acid (CFA) synthase. Surprisingly, isobutanol decreased cyclopropane fatty acid content despite robust upregulation of CFA synthase. Overexpression of the native Z. mobilis' CFA synthase increased cyclopropane fatty acid content in all phospholipid classes and was associated with a significant improvement in growth rates in the presence of added ethanol and isobutanol. Heterologous expression of CFA synthase from Clostridium acetobutylicum resulted in a near complete replacement of unsaturated fatty acids with cyclopropane fatty acids, affecting all lipid classes. However, this did not translate to improved growth rates under isobutanol exposure. Correlating with its greater susceptibility to isobutanol, Z. mobilis exhibited more pronounced alterations in its proteome, metabolome, and overall cell morphology-including cell swelling and formation of intracellular protein aggregates -when exposed to isobutanol compared to ethanol. Isobutanol triggered a broad stress response marked by the upregulation of heat shock proteins, efflux transporters, DNA repair systems, and the downregulation of cell motility proteins. Isobutanol also elicited widespread dysregulation of Z. mobilis' primary metabolism evidenced by increased levels of nucleotide degradation intermediates and the depletion of biosynthetic and glycolytic intermediates. CONCLUSIONS This study provides a comprehensive, systems-level evaluation of the impact of ethanol and isobutanol exposure on the lipid membrane composition and overall physiology of Z. mobilis. These findings will guide engineering of Z. mobilis towards the creation of isobutanol-tolerant strains that can serve as robust platforms for the industrial production of isobutanol from lignocellulosic sugars.
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Affiliation(s)
- Julio Rivera Vazquez
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - Edna Trujillo
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Genome Center of Wisconsin, Madison, WI, USA
| | - Jonathan Williams
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - Fukang She
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - Fitsum Getahun
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - Melanie M Callaghan
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - Joshua J Coon
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Morgridge Institute for Research, Madison, WI, USA
- National Center for Quantitative Biology of Complex Systems, University of Wisconsin-Madison, Madison, WI, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Daniel Amador-Noguez
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, 53726, USA.
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA.
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10
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Möllerke A, Bello J, Leinaas HP, Schulz S. Cyclopropane Hydrocarbons from the Springtail Vertagopus sarekensis─A New Class of Cuticular Lipids from Arthropods. JOURNAL OF NATURAL PRODUCTS 2024; 87:85-97. [PMID: 37957119 PMCID: PMC10825826 DOI: 10.1021/acs.jnatprod.3c00789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/27/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023]
Abstract
The epicuticle of insects is usually coated with a complex mixture of hydrocarbons, primarily straight-chain and methyl-branched alkanes and alkenes. We were interested in whether springtails (Collembola), a sister class of the insects, also use such compounds. We focused here on Vertagopus sarekensis, an abundant Isotomidae species in European high alpine regions, exhibiting coordinated group behavior and migration. This coordination, suggesting chemical communication, made the species interesting for our study on epicuticular hydrocarbons in springtails with different degrees of group behavior. We isolated a single hydrocarbon from its surface, which is the major epicuticular lipid. The structure was deduced by NMR analysis and GC/MS including derivatization. Total synthesis confirmed the structure as cis,cis-3,4,13,14-bismethylene-24-methyldotriacontane (4, sarekensane). The GC/MS analyses of some other cyclopropane hydrocarbons also synthesized showed the close similarity of both mass spectra and gas chromatographic retention indices of alkenes and cyclopropanes. Therefore, analyses of cuticular alkenes must be performed with appropriate derivatization to distinguish these two types of cuticular hydrocarbons. Sarekensane (4) is the first nonterpenoid cuticular hydrocarbon from Collembola that is biosynthesized via the fatty acid pathway, as are insect hydrocarbons, and contains unprecedented cyclopropane rings in the chain, not previously reported from arthropods.
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Affiliation(s)
- Anton Möllerke
- TU
Braunschweig, Institute of Organic Chemistry, Hagenring 30, 38106 Braunschweig, Germany
| | - Jan Bello
- TU
Braunschweig, Institute of Organic Chemistry, Hagenring 30, 38106 Braunschweig, Germany
| | | | - Stefan Schulz
- TU
Braunschweig, Institute of Organic Chemistry, Hagenring 30, 38106 Braunschweig, Germany
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11
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Kim YY, Kim JC, Kim S, Yang JE, Kim HM, Park HW. Heterotypic stress-induced adaptive evolution enhances freeze-drying tolerance and storage stability of Leuconostoc mesenteroides WiKim33. Food Res Int 2024; 175:113731. [PMID: 38128991 DOI: 10.1016/j.foodres.2023.113731] [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: 08/31/2023] [Revised: 11/15/2023] [Accepted: 11/22/2023] [Indexed: 12/23/2023]
Abstract
Lactic acid bacteria (LAB) are currently being investigated for their potential use as probiotics and starter cultures. Researchers have developed powdering processes for the commercialization of LAB. Previous studies have focused on identifying innovative cryoprotective agents and freeze-drying (FD) techniques to enhance the stability of LAB. In this study, adaptive laboratory evolution (ALE) was employed to develop a strain with high FD tolerance and enhanced storage stability. Leuconostoc mesenteroids WiKim33 was subjected to heterotypic shock (heat and osmosis shock) to induce the desired phenotype and genotype. An FD-tolerant enhanced Leu. mesenteroides WiKim33 strain (ALE50) was obtained, which harbored a modified fatty acid composition and cell envelope characteristics. Specifically, ALE50 showed a lower unsaturated fatty acid (UFA)/saturated fatty acid (SFA) ratio and a higher cyclic fatty acid (CFA) composition. Moreover, the exopolysaccharide (EPS) thickness increased significantly by 331% compared to that of the wild type (WT). FD tolerance, which was evaluated using viability testing after FD, was enhanced by 33.4%. Overall, we demonstrated the feasibility of ALE to achieve desirable characteristics and provided insights into the mechanisms underlying increased FD tolerance.
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Affiliation(s)
- Yeong Yeol Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju 61755, Republic of Korea; Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jong-Cheol Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju 61755, Republic of Korea
| | - Seulbi Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju 61755, Republic of Korea; Division of Applied Bioscience & Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jung Eun Yang
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju 61755, Republic of Korea
| | - Ho Myeong Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju 61755, Republic of Korea.
| | - Hae Woong Park
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju 61755, Republic of Korea.
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12
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Brown T, Chavent M, Im W. Molecular Modeling and Simulation of the Mycobacterial Cell Envelope: From Individual Components to Cell Envelope Assemblies. J Phys Chem B 2023; 127:10941-10949. [PMID: 38091517 PMCID: PMC10758119 DOI: 10.1021/acs.jpcb.3c06136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/14/2023] [Accepted: 11/16/2023] [Indexed: 12/29/2023]
Abstract
Unlike typical Gram-positive bacteria, the cell envelope of mycobacteria is unique and composed of a mycobacterial outer membrane, also known as the mycomembrane, a peptidoglycan layer, and a mycobacterial inner membrane, which is analogous to that of Gram-negative bacteria. Despite its importance, however, our understanding of this complex cell envelope is rudimentary at best. Thus, molecular modeling and simulation of such an envelope can benefit the scientific community by proposing new hypotheses about the biophysical properties of its different layers. In this Perspective, we present recent advances in molecular modeling and simulation of the mycobacterial cell envelope from individual components to cell envelope assemblies. We also show how modeling other types of cell envelopes, such as that of Escherichia coli, may help modeling part of the mycobacterial envelopes. We hope that the studies presented here are just the beginning of the road and more and more new modeling and simulation studies help us to understand crucial questions related to mycobacteria such as antibiotic resistance or bacterial survival in the host.
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Affiliation(s)
- Turner Brown
- Department
of Bioengineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Matthieu Chavent
- Institut
de Pharmacologie et Biologie Structurale, CNRS, Université
de Toulouse, 205 Route de Narbonne, 31400 Toulouse, France
| | - Wonpil Im
- Department
of Bioengineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
- Departments
of Biological Sciences and Chemistry, Lehigh
University, Bethlehem, Pennsylvania 18015, United States
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13
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Carrasco V, Roldán DM, Valenzuela-Ibaceta F, Lagos-Moraga S, Dietz-Vargas C, Menes RJ, Pérez-Donoso JM. Pseudomonas violetae sp. nov. and Pseudomonas emilianonis sp. nov., two new species with the ability to degrade TNT isolated from soil samples at Deception Island, maritime Antarctica. Arch Microbiol 2023; 206:39. [PMID: 38142428 DOI: 10.1007/s00203-023-03768-6] [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: 09/22/2023] [Revised: 11/13/2023] [Accepted: 11/23/2023] [Indexed: 12/26/2023]
Abstract
Two motile, rod-shaped, Gram-stain-negative bacterial strains, TNT11T and TNT19T, were isolated from soil samples collected at Deception Island, Antarctica. According to the 16S rRNA gene sequence similarity, both strains belong to the genus Pseudomonas. Further genomic analyses based on ANI and dDDH suggested that these strains were new species. Growth of strain TNT11T is observed at 0-30 ℃ (optimum, 20 ℃), pH 4.0-9.0 (optimum, pH 6.0) and in the presence of 0-5.0% NaCl (optimum, 1% NaCl), while for TNT19T is observed at 0-30 ℃ (optimum between 15 and 20 ℃), pH 5.0-9.0 (optimum, pH 6.0) and in the presence of 0-5.0% NaCl (optimum between 0 and 1% NaCl). The fatty acid profile consists of the major compounds; C16:0 and C16:1 ω6 for TNT11T, and C16:0 and C12:0 for TNT19T. Based on the draft genome sequences, the DNA G + C content for TNT11T is 60.43 mol% and 58.60 mol% for TNT19T. Based on this polyphasic study, TNT11T and TNT19T represent two novel species of the genus Pseudomonas, for which the proposed names are Pseudomonas violetae sp. nov. and Pseudomonas emilianonis sp. nov., respectively. The type strains are Pseudomonas violetae TNT11T (= RGM 3443T = LMG 32959T) and Pseudomonas emilianonis TNT19T (= RGM 3442T = LMG 32960T). Strains TNT11T and TNT19T were deposited to CChRGM and BCCM/LMG with entry numbers RGM 3443/LMG 32959 and RGM 3442/LMG 32960, respectively.
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Affiliation(s)
- Valentina Carrasco
- BioNanotechnology and Microbiology Laboratory, Center for Bioinformatics and Integrative Biology (CBIB), Facultad de Ciencias Biológicas, Universidad Andres Bello, Av. República 330, Santiago, Chile
| | - Diego M Roldán
- Laboratorio de Microbiología, Unidad Asociada del Instituto de Química Biológica, Facultad de Ciencias, Universidad de La República, Montevideo, Uruguay
- Laboratorio de Ecología Microbiana Medioambiental, Facultad de Química, Universidad de La República, Montevideo, Uruguay
| | - Felipe Valenzuela-Ibaceta
- BioNanotechnology and Microbiology Laboratory, Center for Bioinformatics and Integrative Biology (CBIB), Facultad de Ciencias Biológicas, Universidad Andres Bello, Av. República 330, Santiago, Chile
| | - Sebastián Lagos-Moraga
- BioNanotechnology and Microbiology Laboratory, Center for Bioinformatics and Integrative Biology (CBIB), Facultad de Ciencias Biológicas, Universidad Andres Bello, Av. República 330, Santiago, Chile
| | - Claudio Dietz-Vargas
- BioNanotechnology and Microbiology Laboratory, Center for Bioinformatics and Integrative Biology (CBIB), Facultad de Ciencias Biológicas, Universidad Andres Bello, Av. República 330, Santiago, Chile
| | - Rodolfo Javier Menes
- Laboratorio de Microbiología, Unidad Asociada del Instituto de Química Biológica, Facultad de Ciencias, Universidad de La República, Montevideo, Uruguay
- Laboratorio de Ecología Microbiana Medioambiental, Facultad de Química, Universidad de La República, Montevideo, Uruguay
| | - José M Pérez-Donoso
- BioNanotechnology and Microbiology Laboratory, Center for Bioinformatics and Integrative Biology (CBIB), Facultad de Ciencias Biológicas, Universidad Andres Bello, Av. República 330, Santiago, Chile.
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14
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Linney JA, Routledge SJ, Connell SD, Larson TR, Pitt AR, Jenkinson ER, Goddard AD. Identification of membrane engineering targets for increased butanol tolerance in Clostridium saccharoperbutylacetonicum. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184217. [PMID: 37648011 DOI: 10.1016/j.bbamem.2023.184217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 07/17/2023] [Accepted: 08/17/2023] [Indexed: 09/01/2023]
Abstract
There is a growing interest in the use of microbial cell factories to produce butanol, an industrial solvent and platform chemical. Biobutanol can also be used as a biofuel and represents a cleaner and more sustainable alternative to the use of conventional fossil fuels. Solventogenic Clostridia are the most popular microorganisms used due to the native expression of butanol synthesis pathways. A major drawback to the wide scale implementation and development of these technologies is the toxicity of butanol. Various membrane properties and related functions are perturbed by the interaction of butanol with the cell membrane, causing lower yields and higher purification costs. This is ultimately why the technology remains underemployed. This study aimed to develop a deeper understanding of butanol toxicity at the membrane to determine future targets for membrane engineering. Changes to the lipidome in Clostridium saccharoperbutylacetonicum N1-4 (HMT) throughout butanol fermentation were investigated with thin layer chromatography and mass spectrometry. By the end of fermentation, levels of phosphatidylglycerol lipids had increased significantly, suggesting an important role of these lipid species in tolerance to butanol. Using membrane models and in vitro assays to investigate characteristics such as permeability, fluidity, and swelling, it was found that altering the composition of membrane models can convey tolerance to butanol, and that modulating membrane fluidity appears to be a key factor. Data presented here will ultimately help to inform rational strain engineering efforts to produce more robust strains capable of producing higher butanol titres.
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Affiliation(s)
- John A Linney
- School of Health and Life Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
| | - Sarah J Routledge
- School of Health and Life Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
| | - Simon D Connell
- School of Physics and Astronomy and The Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Tony R Larson
- Department of Biology, University of York, York YO10 5DD, UK
| | - Andrew R Pitt
- Manchester Institute of Biotechnology, University of Manchester, Manchester M1 7DN, UK
| | | | - Alan D Goddard
- School of Health and Life Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK.
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15
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Fordjour E, Bai Z, Li S, Li S, Sackey I, Yang Y, Liu CL. Improved Membrane Permeability via Hypervesiculation for In Situ Recovery of Lycopene in Escherichia coli. ACS Synth Biol 2023; 12:2725-2739. [PMID: 37607052 DOI: 10.1021/acssynbio.3c00306] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Lycopene biosynthesis is frequently hampered by downstream processing hugely due to its inability to be secreted out from the producing chassis. Engineering cell factories can resolve this issue by secreting this hydrophobic compound. A highly permeable E. coli strain was developed for a better release rate of lycopene. Specifically, the heterologous mevalonate pathway and crtEBI genes from Corynebacterium glutamicum were overexpressed in Escherichia coli BL21 (DE3) for lycopene synthesis. To ensure in situ lycopene production, murein lipoprotein, lipoprotein NlpI, inner membrane permease protein, and membrane-anchored protein in TolA-TolQ-TolR were deleted for improved membrane permeability. The final strain, LYC-8, produced 438.44 ± 8.11 and 136.94 ± 1.94 mg/L of extracellular and intracellular lycopene in fed-batch fermentation. Both proteomics and lipidomics analyses of secreted outer membrane vesicles were perfect indicators of hypervesiculation. Changes in the ratio of saturated fatty acids, unsaturated fatty acids, and cyclopropane fatty acids coupled with the branching and acyl chain lengths altered the membrane fatty acid composition. This ensured membrane fluidity and permeability for in situ lycopene release. The combinatorial deletion of these genes altered the cellular morphology. The structural and morphological changes in cell shape, size, and length were associated with changes in the mechanical strength of the cell envelope. The enhanced lycopene production and secretion mediated by improved membrane permeability established a cell lysis-free system for an efficient releasing rate and downstream processing, demonstrating the importance of vesicle-associated membrane permeability in efficient lycopene production.
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Affiliation(s)
- Eric Fordjour
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center of Cereal Fermentation, and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
- Jiangsu Provincial Research Centre for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Zhonghu Bai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center of Cereal Fermentation, and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
- Jiangsu Provincial Research Centre for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Sihan Li
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center of Cereal Fermentation, and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
- Jiangsu Provincial Research Centre for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Shijie Li
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center of Cereal Fermentation, and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
- Jiangsu Provincial Research Centre for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Isaac Sackey
- Department of Biological Sciences, Faculty of Biosciences, University for Development Studies, P.O. Box TL1350, NT-0272-1946 Tamale, Ghana
| | - Yankun Yang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center of Cereal Fermentation, and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
- Jiangsu Provincial Research Centre for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
| | - Chun-Li Liu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- National Engineering Research Center of Cereal Fermentation, and Food Biomanufacturing, Jiangnan University, Wuxi 214122, China
- Jiangsu Provincial Research Centre for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, China
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16
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Pan Z, Guo J, Zhong Y, Fan L, Su Y. Gentamicin resistance to Escherichia coli related to fatty acid metabolism based on transcriptome analysis. Can J Microbiol 2023; 69:328-338. [PMID: 37224563 DOI: 10.1139/cjm-2023-0036] [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] [Indexed: 05/26/2023]
Abstract
Antibiotic overuse and misuse have promoted the emergence and spread of antibiotic-resistant bacteria. Increasing bacterial resistance to antibiotics is a major healthcare problem, necessitating elucidation of antibiotic resistance mechanisms. In this study, we explored the mechanism of gentamicin resistance by comparing the transcriptomes of antibiotic-sensitive and -resistant Escherichia coli. A total of 410 differentially expressed genes were identified, of which 233 (56.83%) were up-regulated and 177 (43.17%) were down-regulated in the resistant strain compared with the sensitive strain. Gene Ontology (GO) analysis classifies differential gene expression into three main categories: biological processes, cellular components, and molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that the up-regulated genes were enriched in eight metabolic pathways, including fatty acid metabolism, which suggests that fatty acid metabolism may be involved in the development of gentamicin resistance in E. coli. This was demonstrated by measuring the acetyl-CoA carboxylase activity, plays a fundamental role in fatty acid metabolism, was increased in gentamicin-resistant E. coli. Treatment of fatty acid synthesis inhibitor, triclosan, promoted gentamicin-mediated killing efficacy to antibiotic-resistant bacteria. We also found that exogenous addition of oleic acid, which involved in fatty acid metabolism, reduced E. coli sensitivity to gentamicin. Overall, our results provide insight into the molecular mechanism of gentamicin resistance development in E. coli.
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Affiliation(s)
- Zhiyu Pan
- Department of Cell Biology & Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, MOE Key Laboratory of Tumor Molecular Biology, Guangdong Provincial Key Laboratory of Bioengineering Medicine, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Juan Guo
- Department of Cell Biology & Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, MOE Key Laboratory of Tumor Molecular Biology, Guangdong Provincial Key Laboratory of Bioengineering Medicine, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Yilin Zhong
- Department of Cell Biology & Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, MOE Key Laboratory of Tumor Molecular Biology, Guangdong Provincial Key Laboratory of Bioengineering Medicine, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Lvyuan Fan
- Department of Cell Biology & Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, MOE Key Laboratory of Tumor Molecular Biology, Guangdong Provincial Key Laboratory of Bioengineering Medicine, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Yubin Su
- Department of Cell Biology & Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, MOE Key Laboratory of Tumor Molecular Biology, Guangdong Provincial Key Laboratory of Bioengineering Medicine, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
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17
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Zhu X, Guo Z, Wang N, Liu J, Zuo Y, Li K, Song C, Song Y, Gong C, Xu X, Yuan F, Zhang L. Environmental stress stimulates microbial activities as indicated by cyclopropane fatty acid enhancement. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 873:162338. [PMID: 36813189 DOI: 10.1016/j.scitotenv.2023.162338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/24/2023] [Accepted: 02/15/2023] [Indexed: 06/18/2023]
Abstract
Soil microbial responses to environmental stress remain a critical question in microbial ecology. The content of cyclopropane fatty acid (CFA) in cytomembrane has been widely used to evaluate environmental stress on microorganisms. Here, we used CFA to investigate the ecological suitability of microbial communities and found a stimulating impact of CFA on microbial activities during wetland reclamation in Sanjiang Plain, Northeastern China. The seasonality of environmental stress resulted in the fluctuation of CFA content in the soil, which suppressed microbial activities due to nutrient loss upon wetland reclamation. After land conversion, the aggravation of temperature stress to microbes increased the CFA content by 5 % (autumn) to 163 % (winter), which led to the suppression of microbial activities by 7 %-47 %. By contrast, the warmer soil temperature and permeability decreased the CFA content by 3 % to 41 % and consequently aggravated the microbial reduction by 15 %-72 % in spring and summer. Complex microbial communities of 1300 CFA-produced species were identified using a sequencing approach, suggesting that soil nutrients dominated the differentiation in these microbial community structures. Further analysis with structural equation modeling highlighted the important function of CFA content to environmental stress and the stimulating influence of CFA induced by environmental stress on microbial activities. Our study shows the biological mechanisms of seasonal CFA content for microbial adaption to environmental stress under wetland reclamation. It advances our knowledge of microbial physiology affecting soil element cycling caused by anthropogenic activities.
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Affiliation(s)
- Xinhao Zhu
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China; Biology Department, San Diego State University, San Diego, CA 92182, USA
| | - Ziyu Guo
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Nannan Wang
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China
| | - Jianzhao Liu
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunjiang Zuo
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kexin Li
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Changchun Song
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China
| | - Yanyu Song
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China
| | - Chao Gong
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China
| | - Xiaofeng Xu
- Biology Department, San Diego State University, San Diego, CA 92182, USA
| | - Fenghui Yuan
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China; Department of Soil, Water, and Climate, University of Minnesota, Saint Paul, MN 55108, USA.
| | - Lihua Zhang
- Key Laboratory of Ecology and Environment in Minority Areas, Minzu University of China, Beijing 100081, China.
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18
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Ramires T, Wilson R, Padilha da Silva W, Bowman JP. Identification of pH-specific protein expression responses by Campylobacter jejuni strain NCTC 11168. Res Microbiol 2023:104061. [PMID: 37055003 DOI: 10.1016/j.resmic.2023.104061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/21/2023] [Accepted: 04/06/2023] [Indexed: 04/15/2023]
Abstract
In this study a data dependent acquisition label-free based proteomics approach was used to identify pH-dependent proteins that respond in a growth phase independent manner in C. jejuni reference strain NCTC 11168. NCTC 11168 was grown within its pH physiological normal growth range (pH 5.8, 7.0 and 8.0, μ = ∼0.5 h-1) and exposed to pH 4.0 shock for 2 hours. It was discovered that gluconate 2-dehydrogenase GdhAB, NssR-regulated globins Cgb and Ctb, cupin domain protein Cj0761, cytochrome c protein CccC (Cj0037c), and phosphate-binding transporter protein PstB all show acidic pH dependent abundance increases but are not activated by sub-lethal acid shock. Glutamate synthase (GLtBD) and the MfrABC and NapAGL respiratory complexes were induced in cells grown at pH 8.0. The response to pH stress by C. jejuni is to bolster microaerobic respiration and at pH 8.0 this is assisted by accumulation of glutamate the conversion of which could bolster fumarate respiration. The pH dependent proteins linked to growth in C. jejuni NCTC 11168 aids cellular energy conservation maximising growth rate and thus competitiveness and fitness.
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Affiliation(s)
- Tassiana Ramires
- Departamento de Ciência e Tecnologia Agroindustrial, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Richard Wilson
- Central Science Laboratory, University of Tasmania, Hobart, Tasmania, Australia
| | - Wladimir Padilha da Silva
- Departamento de Ciência e Tecnologia Agroindustrial, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - John P Bowman
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tasmania, Australia.
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19
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Shenault DM, McLuckey SA, Franklin ET. Localization of cyclopropyl groups and alkenes within glycerophospholipids using gas-phase ion/ion chemistry. JOURNAL OF MASS SPECTROMETRY : JMS 2023; 58:e4913. [PMID: 36916143 PMCID: PMC10014902 DOI: 10.1002/jms.4913] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 02/07/2023] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
Shotgun lipid analysis using electrospray ionization tandem mass spectrometry (ESI-MS/MS) is a common approach for the identification and characterization of glycerophohspholipids GPs. ESI-MS/MS, with the aid of collision-induced dissociation (CID), enables the characterization of GP species at the headgroup and fatty acyl sum compositional levels. However, important structural features that are often present, such as carbon-carbon double bond(s) and cyclopropane ring(s), can be difficult to determine. Here, we report the use of gas-phase charge inversion reactions that, in combination with CID, allow for more detailed structural elucidation of GPs. CID of a singly deprotonated GP, [GP - H]- , generates FA anions, [FA - H]- . The fatty acid anions can then react with doubly charged cationic magnesium tris-phenanthroline complex, [Mg(Phen)3 ]2+ , to form charge inverted complex cations of the form [FA - H + MgPhen2 ]+ . CID of the complex generates product ion spectral patterns that allow for the identification of carbon-carbon double bond position(s) as well as the sites of cyclopropyl position(s) in unsaturated lipids. This approach to determining both double bond and cyclopropane positions is demonstrated with GPs for the first time using standards and is applied to lipids extracted from Escherichia coli.
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Affiliation(s)
- De’Shovon M. Shenault
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, United States, 47907-2084
| | - Scott A. McLuckey
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, United States, 47907-2084
| | - Elissia T. Franklin
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, United States, 47907-2084
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20
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Metryka O, Wasilkowski D, Adamczyk-Habrajska M, Mrozik A. Undesirable consequences of the metallic nanoparticles action on the properties and functioning of Escherichia coli, Bacillus cereus and Staphylococcus epidermidis membranes. JOURNAL OF HAZARDOUS MATERIALS 2023; 446:130728. [PMID: 36610340 DOI: 10.1016/j.jhazmat.2023.130728] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/03/2023] [Accepted: 01/03/2023] [Indexed: 06/17/2023]
Abstract
Controversial and inconsistent findings on the toxicity of metallic nanoparticles (NPs) against many bacteria are common in recorded studies; therefore, further advanced experimental work is needed to elucidate the mechanisms underlying nanotoxicity. This study deciphered the direct effects of Ag-NPs, Cu-NPs, ZnO-NPs and TiO2-NPs on membrane permeability, cytoplasmic leakage, ATP level, ATPase activity and fatty acid profiling of Escherichia coli, Bacillus cereus and Staphylococcus epidermidis as model microorganisms. A multifaceted analysis of all collected results indicated the different influences of individual NPs on the measured parameters depending on their type and concentration. Predominantly, membrane permeability was correlated with increased cytoplasmic leakage, reduced total ATP levels and ATPase activity. The established fatty acid profiles were unique and concerned various changes in the percentages of hydroxyl, cyclopropane, branched and unsaturated fatty acids. Decisively, E. coli was more susceptible to changes in measured parameters than B. cereus and S. epidermidis. Also, it was established that ZnO-NPs and Cu-NPs had a major differentiating impact on studied parameters. Additionally, bacterial cell imaging using scanning electron microscopy elucidated different NPs distributions on the cell surface. The presented results are believed to provide novel, valuable and accumulated knowledge in the understanding of NPs action on bacterial membranes.
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Affiliation(s)
- Oliwia Metryka
- Doctoral School, University of Silesia, Bankowa 14, Katowice 40-032, Poland.
| | - Daniel Wasilkowski
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, Jagiellońska 29, Katowice 40-032, Poland
| | - Małgorzata Adamczyk-Habrajska
- Institute of Materials Engineering, Faculty of Science and Technology, University of Silesia, Żytnia 12, Sosnowiec 41-200, Poland
| | - Agnieszka Mrozik
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, Jagiellońska 29, Katowice 40-032, Poland.
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21
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Maiti A, Kumar A, Daschakraborty S. How Do Cyclopropane Fatty Acids Protect the Cell Membrane of Escherichia coli in Cold Shock? J Phys Chem B 2023; 127:1607-1617. [PMID: 36790194 DOI: 10.1021/acs.jpcb.3c00541] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The cyclopropanation of unsaturated lipid acyl chains of some bacterial cell membranes is an important survival strategy to protect the same against drastic cooling. To elucidate the role of cyclopropane ring-containing lipids, we have simulated the lipid membrane of Escherichia coli (E. coli) and two modified membranes by replacing the cyclopropane rings with either single or double bonds at widely different temperatures. It has been observed that the cyclopropane rings provide more rigid kinks in the lipid acyl chain compared to the double bonds and therefore further reduce the packing density of the membrane and subsequently enhance the membrane fluidity at low temperatures. They also inhibit the close packing of other lipids and deleterious phase separation by strongly interacting with them. Therefore, this study has explained why E. coli bacterial strain, susceptible to freezing environments, relies on the cyclopropanation of an unsaturated chain.
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Affiliation(s)
- Archita Maiti
- Department of Chemistry, Indian Institute of Technology Patna, Patna, Bihar 801106, India
| | - Abhay Kumar
- Department of Chemistry, Indian Institute of Technology Patna, Patna, Bihar 801106, India
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22
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O'Brien RA, Hillesheim PC, Soltani M, Badilla-Nunez KJ, Siu B, Musozoda M, West KN, Davis JH, Mirjafari A. Cyclopropane as an Unsaturation "Effect Isostere": Lowering the Melting Points in Lipid-like Ionic Liquids. J Phys Chem B 2023; 127:1429-1442. [PMID: 36745872 DOI: 10.1021/acs.jpcb.2c07872] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The replacement of unsaturation with a cyclopropane motif as a (bio)isostere is a widespread strategy in bacteria to tune the fluidity of lipid bilayers and protect membranes when exposed to adverse environmental conditions, e.g., high temperature, low pH, etc. Inspired by this phenomenon, we herein address the relative effect of the cyclopropanation, both cis and trans configurations, on melting points, packing efficiency, and order of a series of lipid-like ionic liquids via a combination of thermophysical analysis, X-ray crystallography, and computational modeling. The data indicate there is considerable structural latitude possible when designing highly lipophilic ionic liquids that exhibit low melting points. While cyclopropanation of the lipid-like ionic liquids provides more resistance to aerobic degradation than their olefin analogs, the impact on the melting point decrease is not as pronounced. Our results demonstrate that incorporating one or more cyclopropyl moieties in long aliphatic chains of imidazolium-based ionic liquids is highly effective in lowering the melting points of such materials relative to their counterparts bearing linear, saturated, or thioether side chains. It is shown that the cyclopropane moiety effectively disrupts packing, favoring formation of gauche conformer in the side chains, resulting in enhancement of fluidity. This was irrespective of the configuration of the methylene bridge, although marked differences in the effect of cis- and trans-monocyclopropanated ILs on the melting points were observed.
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Affiliation(s)
- Richard A O'Brien
- Department of Chemistry, The University of South Alabama, Mobile, Alabama 36688, United States
| | - Patrick C Hillesheim
- Department of Chemistry and Physics, Ave Maria University, Ave Maria, Florida 34142, United States
| | - Mohammad Soltani
- Department of Chemistry, The University of South Alabama, Mobile, Alabama 36688, United States
| | - Kelly J Badilla-Nunez
- Department of Chemical and Biomolecular Engineering, The University of South Alabama, Mobile, Alabama 36688, United States
| | - Ben Siu
- Department of Chemical and Biomolecular Engineering, The University of South Alabama, Mobile, Alabama 36688, United States
| | - Muhammadiqboli Musozoda
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, United States
| | - Kevin N West
- Department of Chemical and Biomolecular Engineering, The University of South Alabama, Mobile, Alabama 36688, United States
| | - James H Davis
- Department of Chemistry, The University of South Alabama, Mobile, Alabama 36688, United States
| | - Arsalan Mirjafari
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, United States
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23
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Goudriaan M, Morales VH, van der Meer MTJ, Mets A, Ndhlovu RT, van Heerwaarden J, Simon S, Heuer VB, Hinrichs KU, Niemann H. A stable isotope assay with 13C-labeled polyethylene to investigate plastic mineralization mediated by Rhodococcus ruber. MARINE POLLUTION BULLETIN 2023; 186:114369. [PMID: 36462423 DOI: 10.1016/j.marpolbul.2022.114369] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 10/10/2022] [Accepted: 11/11/2022] [Indexed: 06/17/2023]
Abstract
Methods that unambiguously prove microbial plastic degradation and allow for quantification of degradation rates are necessary to constrain the influence of microbial degradation on the marine plastic budget. We developed an assay based on stable isotope tracer techniques to determine microbial plastic mineralization rates in liquid medium on a lab scale. For the experiments, 13C-labeled polyethylene (13C-PE) particles (irradiated with UV-light to mimic exposure of floating plastic to sunlight) were incubated in liquid medium with Rhodococcus ruber as a model organism for proof of principle. The transfer of 13C from 13C-PE into the gaseous and dissolved CO2 pools translated to microbially mediated mineralization rates of up to 1.2 % yr-1 of the added PE. After incubation, we also found highly 13C-enriched membrane fatty acids of R. ruber including compounds involved in cellular stress responses. We demonstrated that isotope tracer techniques are a valuable tool to detect and quantify microbial plastic degradation.
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Affiliation(s)
- Maaike Goudriaan
- Department of Marine Microbiology and Biogeochemistry (MMB), Royal Netherlands Institute of Sea Research (NIOZ), 1797 SZ 't Horntje, the Netherlands.
| | - Victor Hernando Morales
- Department of Marine Microbiology and Biogeochemistry (MMB), Royal Netherlands Institute of Sea Research (NIOZ), 1797 SZ 't Horntje, the Netherlands; Centro de Investigación Mariña, University of Vigo, Department of Ecology and Animal Biology, Biological Oceanography Group, 36319 Vigo, Spain
| | - Marcel T J van der Meer
- Department of Marine Microbiology and Biogeochemistry (MMB), Royal Netherlands Institute of Sea Research (NIOZ), 1797 SZ 't Horntje, the Netherlands
| | - Anchelique Mets
- Department of Marine Microbiology and Biogeochemistry (MMB), Royal Netherlands Institute of Sea Research (NIOZ), 1797 SZ 't Horntje, the Netherlands
| | - Rachel T Ndhlovu
- Department of Marine Microbiology and Biogeochemistry (MMB), Royal Netherlands Institute of Sea Research (NIOZ), 1797 SZ 't Horntje, the Netherlands
| | - Johan van Heerwaarden
- Department of Marine Microbiology and Biogeochemistry (MMB), Royal Netherlands Institute of Sea Research (NIOZ), 1797 SZ 't Horntje, the Netherlands
| | - Sina Simon
- MARUM-Center for Marine Environmental Sciences, University of Bremen, 28334 Bremen, Germany
| | - Verena B Heuer
- MARUM-Center for Marine Environmental Sciences, University of Bremen, 28334 Bremen, Germany
| | - Kai-Uwe Hinrichs
- MARUM-Center for Marine Environmental Sciences, University of Bremen, 28334 Bremen, Germany
| | - Helge Niemann
- Department of Marine Microbiology and Biogeochemistry (MMB), Royal Netherlands Institute of Sea Research (NIOZ), 1797 SZ 't Horntje, the Netherlands; Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584 CB Utrecht, the Netherlands; CAGE-Centre for Arctic Gas Hydrate, Environment and Climate, Department of Geosciences, UiT the Arctic University of Norway, 9037 Tromsø, Norway.
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24
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Transient Complexity of E. coli Lipidome Is Explained by Fatty Acyl Synthesis and Cyclopropanation. Metabolites 2022; 12:metabo12090784. [PMID: 36144187 PMCID: PMC9500627 DOI: 10.3390/metabo12090784] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 12/04/2022] Open
Abstract
In the case of many bacteria, such as Escherichia coli, the composition of lipid molecules, termed the lipidome, temporally adapts to different environmental conditions and thus modifies membrane properties to permit growth and survival. Details of the relationship between the environment and lipidome composition are lacking, particularly for growing cultures under either favourable or under stress conditions. Here, we highlight compositional lipidome changes by describing the dynamics of molecular species throughout culture-growth phases. We show a steady cyclopropanation of fatty acyl chains, which acts as a driver for lipid diversity. There is a bias for the cyclopropanation of shorter fatty acyl chains (FA 16:1) over longer ones (FA 18:1), which likely reflects a thermodynamic phenomenon. Additionally, we observe a nearly two-fold increase in saturated fatty acyl chains in response to the presence of ampicillin and chloramphenicol, with consequences for membrane fluidity and elasticity, and ultimately bacterial stress tolerance. Our study provides the detailed quantitative lipidome composition of three E. coli strains across culture-growth phases and at the level of the fatty acyl chains and provides a general reference for phospholipid composition changes in response to perturbations. Thus, lipidome diversity is largely transient and the consequence of lipid synthesis and cyclopropanation.
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25
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van Aalst EJ, Borcik CG, Wylie BJ. Spectroscopic signatures of bilayer ordering in native biological membranes. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183891. [PMID: 35217001 PMCID: PMC10793244 DOI: 10.1016/j.bbamem.2022.183891] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/08/2022] [Accepted: 02/09/2022] [Indexed: 06/14/2023]
Abstract
Membrane proteins and polycyclic lipids like cholesterol and hopanoids coordinate phospholipid bilayer ordering. This phenomenon manifests as partitioning of the liquid crystalline phase into liquid-ordered (Lo) and liquid-disordered (Ld) regions. In Eukaryotes, microdomains are rich in cholesterol and sphingolipids and serve as signal transduction scaffolds. In Prokaryotes, Lo microdomains increase pathogenicity and antimicrobial resistance. Previously, we identified spectroscopically distinct chemical shift signatures for all-trans (AT) and trans-gauche (TG) acyl chain conformations, cyclopropyl ring lipids (CPR), and hopanoids in prokaryotic lipid extracts and used Polarization Transfer (PT) SSNMR to investigate bilayer ordering. To investigate how these findings relate to native bilayer organization, we interrogate whole cell and whole membrane extract samples of Burkholderia thailendensis to investigate bilayer ordering in situ. In 13C-13C 2D SSNMR spectra, we assigned chemical shifts for lipid species in both samples, showing conservation of lipids of interest in our native membrane sample. A one-dimensional temperature series of PT SSNMR and transverse relaxation measurements of AT versus TG acyl conformations in the membrane sample confirm bilayer ordering and a broadened phase transition centered at a lower-than-expected temperature. Bulk protein backbone Cα dynamics and correlations consistent with lipid-protein contacts within are further indicative of microdomain formation and lipid ordering. In aggregate, these findings provide evidence for microdomain formation in vivo and provide insight into phase separation and transition mechanics in biological membranes.
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Affiliation(s)
- Evan J van Aalst
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79415, USA
| | - Collin G Borcik
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79415, USA
| | - Benjamin J Wylie
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79415, USA.
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26
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Zhang W, Jian R, Zhao J, Liu Y, Xia Y. Deep-lipidotyping by mass spectrometry: recent technical advances and applications. J Lipid Res 2022; 63:100219. [PMID: 35489417 PMCID: PMC9213770 DOI: 10.1016/j.jlr.2022.100219] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 12/18/2022] Open
Abstract
In-depth structural characterization of lipids is an essential component of lipidomics. There has been a rapid expansion of mass spectrometry methods that are capable of resolving lipid isomers at various structural levels over the past decade. These developments finally make deep-lipidotyping possible, which provides new means to study lipid metabolism and discover new lipid biomarkers. In this review, we discuss recent advancements in tandem mass spectrometry (MS/MS) methods for identification of complex lipids beyond the species (known headgroup information) and molecular species (known chain composition) levels. These include identification at the levels of carbon-carbon double bond (C=C) location and sn-position as well as characterization of acyl chain modifications. We also discuss the integration of isomer-resolving MS/MS methods with different lipid analysis workflows and their applications in lipidomics. The results showcase the distinct capabilities of deep-lipidotyping in untangling the metabolism of individual isomers and sensitive phenotyping by using relative fractional quantitation of the isomers.
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Affiliation(s)
- Wenpeng Zhang
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing 100084, P. R. China
| | - Ruijun Jian
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biological, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China
| | - Jing Zhao
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biological, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China
| | - Yikun Liu
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing 100084, P. R. China
| | - Yu Xia
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biological, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
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27
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Advances in the Structural Biology, Mechanism, and Physiology of Cyclopropane Fatty Acid Modifications of Bacterial Membranes. Microbiol Mol Biol Rev 2022; 86:e0001322. [PMID: 35435731 PMCID: PMC9199407 DOI: 10.1128/mmbr.00013-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cyclopropane fatty acid (CFA) synthase catalyzes a remarkable reaction. The
cis
double bonds of unsaturated fatty acyl chains of phospholipid bilayers are converted to cyclopropane rings by transfer of a methylene moiety from S-adenosyl-L-methionine (SAM).
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28
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Lin Q, Li P, Jian R, Xia Y. Localization of Intrachain Modifications in Bacterial Lipids Via Radical-Directed Dissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:714-721. [PMID: 35195000 DOI: 10.1021/jasms.2c00011] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Intrachain modifications of membrane glycerophospholipids (GPLs) due to formation of the carbon-carbon double bond (C═C), cyclopropane ring, and methyl branching are crucial for bacterial membrane homeostasis. Conventional collision-induced dissociation (CID) of even-electron ions of GPL favors charge-directed fragmentation channels, and thus little structurally informative fragments can be detected for locating intrachain modifications. In this study, we report a radical-directed dissociation (RDD) approach for characterization of the intrachain modifications within phosphoethanolamines (PEs), a major lipid component in bacterial membrane. In this method, a radical precursor that can produce benzyl or pyridine methyl radical upon low-energy CID at high efficiency is conjugated onto the amine group of PEs. The carbon-centered radical ions subsequently initiate RDD along the fatty acyl chain, producing fragment patterns key to the assignment and localization of intrachain modifications including C═C, cyclopropane rings, and methyl branching. Besides intrachain fragmentation, RDD on the glycerol backbone produces fatty acyl loss as radicals, allowing one to identify the fatty acyl chain composition of PE. Moreover, RDD of lyso-PEs produces radical losses for distinguishing the sn-isomers. The above RDD approach has been incorporated onto a liquid chromatography-mass spectrometry workflow and applied for the analysis of lipid extracts from Escherichia coli and Bacillus subtilis.
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Affiliation(s)
- Qiaohong Lin
- Department of Chemistry, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing 10084, China
| | - Pengyun Li
- National Engineering Research Center for the Emergency Drug, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China
| | - Ruijun Jian
- Department of Chemistry, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing 10084, China
| | - Yu Xia
- Department of Chemistry, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing 10084, China
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29
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Multi-Omic Analysis to Characterize Metabolic Adaptation of the E. coli Lipidome in Response to Environmental Stress. Metabolites 2022; 12:metabo12020171. [PMID: 35208246 PMCID: PMC8880424 DOI: 10.3390/metabo12020171] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/08/2022] [Accepted: 02/09/2022] [Indexed: 12/17/2022] Open
Abstract
As an adaptive survival response to exogenous stress, bacteria undergo dynamic remodelling of their lipid metabolism pathways to alter the composition of their cellular membranes. Here, using Escherichia coli as a well characterised model system, we report the development and application of a ‘multi-omics’ strategy for comprehensive quantitative analysis of the temporal changes in the lipidome and proteome profiles that occur under exponential growth phase versus stationary growth phase conditions i.e., nutrient depletion stress. Lipidome analysis performed using ‘shotgun’ direct infusion-based ultra-high resolution accurate mass spectrometry revealed a quantitative decrease in total lipid content under stationary growth phase conditions, along with a significant increase in the mol% composition of total cardiolipin, and an increase in ‘odd-numbered’ acyl-chain length containing glycerophospholipids. The inclusion of field asymmetry ion mobility spectrometry was shown to enable the enrichment and improved depth of coverage of low-abundance cardiolipins, while ultraviolet photodissociation-tandem mass spectrometry facilitated more complete lipid structural characterisation compared with conventional collision-induced dissociation, including unambiguous assignment of the odd-numbered acyl-chains as containing cyclopropyl modifications. Proteome analysis using data-dependent acquisition nano-liquid chromatography mass spectrometry and tandem mass spectrometry analysis identified 83% of the predicted E. coli lipid metabolism enzymes, which enabled the temporal dependence associated with the expression of key enzymes responsible for the observed adaptive lipid metabolism to be determined, including those involved in phospholipid metabolism (e.g., ClsB and Cfa), fatty acid synthesis (e.g., FabH) and degradation (e.g., FadA/B,D,E,I,J and M), and proteins involved in the oxidative stress response resulting from the generation of reactive oxygen species during β-oxidation or lipid degradation.
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30
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Mechanisms of Acetoin Toxicity and Adaptive Responses in an Acetoin-Producing Species, Lactococcus lactis. Appl Environ Microbiol 2021; 87:e0107921. [PMID: 34613757 PMCID: PMC8612267 DOI: 10.1128/aem.01079-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Acetoin, 3-hydroxyl,2-butanone, is extensively used as a flavor additive in food products. This volatile compound is produced by the dairy bacterium Lactococcus lactis when aerobic respiration is activated by haem addition, and comprises ∼70% of carbohydrate degradation products. Here we investigate the targets of acetoin toxicity, and determine how acetoin impacts L. lactis physiology and survival. Acetoin caused damage to DNA and proteins, which related to reactivity of its keto group. Acetoin stress was reflected in proteome profiles, which revealed changes in lipid metabolic proteins. Acetoin provoked marked changes in fatty acid composition, with massive accumulation of cycC19:0 cyclopropane fatty acid at the expense of its unsaturated C18:1 fatty acid precursor. Deletion of the cfa gene, encoding the cycC19:0 synthase, sensitized cells to acetoin stress. Acetoin-resistant transposon mutagenesis revealed a hot spot in the high affinity phosphate transporter operon pstABCDEF, which is known to increase resistance to multiple stresses. This work reveals the causes and consequences of acetoin stress on L. lactis, and may facilitate control of lactic acid bacteria production in technological processes. IMPORTANCE Acetoin, 3-hydroxyl,2-butanone, has diverse uses in chemical industry, agriculture, and dairy industries as a volatile compound that generates aromas. In bacteria, it can be produced in high amount by Lactococcus lactis when it grows under aerobic respiration. However, acetoin production can be toxic and detrimental for growth and/or survival. Our results showed that it damages DNA and proteins via its keto group. We also showed that acetoin modifies membrane fatty acid composition with the production of cyclopropane C19:0 fatty acid at the expense of an unsaturated C18:1. We isolated mutants more resistant to acetoin than the wild-type strain. All of them mapped to a single locus pstABCDEF operon, suggesting a simple means to limit acetoin toxicity in dairy bacteria and to improve its production.
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31
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Metabolomic profiling of Burkholderia cenocepacia in synthetic cystic fibrosis sputum medium reveals nutrient environment-specific production of virulence factors. Sci Rep 2021; 11:21419. [PMID: 34725378 PMCID: PMC8560942 DOI: 10.1038/s41598-021-00421-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 10/12/2021] [Indexed: 12/13/2022] Open
Abstract
Infections by Burkholderia cenocepacia lead to life-threatening disease in immunocompromised individuals, including those living with cystic fibrosis (CF). While genetic variation in various B. cenocepacia strains has been reported, it remains unclear how the chemical environment of CF lung influences the production of small molecule virulence factors by these strains. Here we compare metabolomes of three clinical B. cenocepacia strains in synthetic CF sputum medium (SCFM2) and in a routine laboratory medium (LB), in the presence and absence of the antibiotic trimethoprim. Using a mass spectrometry-based untargeted metabolomics approach, we identify several compound classes which are differentially produced in SCFM2 compared to LB media, including siderophores, antimicrobials, quorum sensing signals, and various lipids. Furthermore, we describe that specific metabolites are induced in the presence of the antibiotic trimethoprim only in SCFM2 when compared to LB. Herein, C13-acyl-homoserine lactone, a quorum sensing signal previously not known to be produced by B. cenocepacia as well as pyochelin-type siderophores were exclusively detected during growth in SCFM2 in the presence of trimethoprim. The comparative metabolomics approach described in this study provides insight into environment-dependent production of secondary metabolites by B. cenocepacia strains and suggests future work which could identify personalized strain-specific regulatory mechanisms involved in production of secondary metabolites. Investigations into whether antibiotics with different mechanisms of action induce similar metabolic alterations will inform development of combination treatments aimed at effective clearance of Burkholderia spp. pathogens.
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32
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Cyclopropane Fatty Acids are Important for Salmonella enterica serovar Typhimurium Virulence. Infect Immun 2021; 90:e0047921. [PMID: 34662213 DOI: 10.1128/iai.00479-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A variety of eubacteria, plants and protozoa can modify membrane lipids by cyclopropanation, which is reported to modulate membrane permeability and fluidity. The ability to cyclopropanate membrane lipids has been associated with resistance to oxidative stress in Mycobacterium tuberculosis, organic solvent stress in Escherichia coli, and acid stress in E. coli and Salmonella. In bacteria, the cfa gene encoding cyclopropane fatty acid (CFA) synthase is induced during the stationary phase of growth. In the present study we constructed a cfa mutant of Salmonella enterica serovar Typhimurium 14028s (S. Typhimurium) and determined the contribution of CFA-modified lipids to stress resistance and virulence in mice. Cyclopropane fatty acid content was quantified in wild-type and cfa mutant S. Typhimurium. CFA levels in a cfa mutant were greatly reduced compared to wild-type, indicating that CFA synthase is the major enzyme responsible for cyclopropane modification of lipids in Salmonella. S. Typhimurium cfa mutants were more sensitive to extreme acid pH, the protonophore CCCP, and hydrogen peroxide, compared to wild-type. In addition, cfa mutants exhibited reduced viability in murine macrophages and could be rescued by addition of the NADPH phagocyte oxidase inhibitor diphenyleneiodonium (DPI) chloride. S. Typhimurium lacking cfa was also attenuated for virulence in mice. These observations indicate that CFA modification of lipids makes an important contribution to Salmonella virulence.
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The challenges and prospects of Escherichia coli as an organic acid production host under acid stress. Appl Microbiol Biotechnol 2021; 105:8091-8107. [PMID: 34617140 DOI: 10.1007/s00253-021-11577-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 09/07/2021] [Accepted: 09/08/2021] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Organic acids have a wide range of applications and have attracted the attention of many industries, and their large-scale applications have led fermentation production to low-cost development. Among them, the microbial fermentation method, especially using Escherichia coli as the production host, has the advantages of fast growth and low energy consumption, and has gradually shown better advantages and prospects in organic acid fermentation production. IMPORTANCE However, when the opportunity comes, the acidified environment caused by the acid products accumulated during the fermentation process also challenges E. coli. The acid sensitivity of E. coli is a core problem that needs to be solved urgently. The addition of neutralizers in traditional operations led to the emergence of osmotic stress inadvertently, the addition of strong acid substances to recover products in the salt state not only increases production costs, but the discharged sewage is also harmful to the environment. ELABORATION This article summarizes the current status of the application of E. coli in the production of organic acids, and based on the impact of acid stress on the physiological state of cells and the impact of industrial production profits, put forward some new conjectures that can make up for the deficiencies in existing research and application. IMPLICATION At this point, the diversified transformation of E. coli has become a chassis microbe that is more suitable for industrial fermentation, enhancing industrial application value. KEY POINTS • E. coli is a potential host for high value-added organic acids production. • Classify the damage mechanism and coping strategies of E. coli when stimulated by acid molecules. • Multi-dimensional expansion tools are needed to create acid-resistant E. coli chassis.
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Lolli V, Caligiani A, Gachiuta O, Pizzamiglio V, Bani P. Study on the Effect of Ensiling Process and Ruminal Digestion on the Synthesis and Release of Cyclopropane Fatty Acids in Cow Feeding. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:11026-11032. [PMID: 34498864 DOI: 10.1021/acs.jafc.1c03204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Cyclopropane fatty acids (CPFA) were found in milk fat from cows fed maize silage and suggested to be synthesized by lactic acid bacteria during ensiling. This study aimed to elucidate some gaps of knowledge about the microbial synthesis of CPFA, to strengthen the current authentication method based on their detection in cheese fat and performed for Parmigiano Reggiano (UNI11650), whose Specifications forbid the use of silage. CPFA were screened in different ensiled cows' feeding by gas chromatography-mass spectrometry, and the effect of feed ingredients and ruminal digestion on CPFA microbial production were further examined by in vitro tests. Results showed that solely the environmental conditions developed in silos for specific plant materials (e.g., maize) are essential for the bacterial synthesis of CPFA, whereas rumen activity did not affect CPFA levels in feeds. This supports the suitability of using CPFA as biomarkers of a crop silage-based diet forbidden by certain PDO feedstock regulations.
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Affiliation(s)
- Veronica Lolli
- Department of Food and Drug, University of Parma, Parco Area delle Scienze 17/A, 43123 Parma, Italy
| | - Augusta Caligiani
- Department of Food and Drug, University of Parma, Parco Area delle Scienze 17/A, 43123 Parma, Italy
| | - Olga Gachiuta
- Department of Animal Science, Food and Nutrition, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, 29122 Piacenza, Italy
| | - Valentina Pizzamiglio
- Consorzio del formaggio Parmigiano Reggiano, Via J.F. Kennedy 18, 42124 Reggio Emilia, Italy
| | - Paolo Bani
- Department of Animal Science, Food and Nutrition, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, 29122 Piacenza, Italy
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Type II fatty acid synthesis pathway and cyclopropane ring formation are dispensable during Enterococcus faecalis systemic infection. J Bacteriol 2021; 203:e0022121. [PMID: 34309397 DOI: 10.1128/jb.00221-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterococcus faecalis, a multi-antibiotic-resistant Gram-positive bacterium, has emerged as a serious nosocomial pathogen. Here, we used a genetic approach to characterize the strategies used by E. faecalis to fulfill its requirements for endogenous fatty acid (FA) synthesis in vitro and in vivo. The FA synthesis (FASII) pathway is encoded by two operons and two monocistronic genes. Expression of all these genes is repressed by exogenous FAs, which are incorporated in the E. faecalis membrane and modify its composition. Deletion of nine genes of the 12-gene operon abolished growth in a FA-free medium. Addition of serum, which is lipid-rich, restored growth. Interestingly, the E. faecalis membrane contains cyclic fatty acids that modify membrane properties, but are unavailable in host serum. The cfa gene that encodes the cyclopropanation process, is located in a locus independent of the FASII genes. Its deletion did not alter growth under the conditions tested, but yielded bacteria devoid of cyclic FAs. No differences were observed between mice infected with wild-type, or FASII or cyclopropanation mutant strains, in terms of bacterial loads in blood, liver, spleen or kidneys. We conclude that in E. faecalis, neither FASII nor cyclopropanation enzymes are suitable antibiotic targets. Importance Membrane lipid homeostasis is crucial for bacterial physiology, adaptation, and virulence. Fatty acids are constituents of the phospholipids that are essential membrane components. Most bacteria incorporate exogenous fatty acids into their membranes. Enterococcus faecalis has emerged as a serious nosocomial pathogen, which is responsible for urinary tract infections, bacteremia and endocarditis, and is intrinsically resistant to numerous antibiotics. E. faecalis synthesizes saturated and unsaturated fatty acids, but also cyclic fatty acids that are not found in the human host. We characterized mutant strains deficient in fatty acid synthesis and modification using genetic, biochemical, and in vivo approaches. We conclude that neither the fatty acid synthesis pathway nor the cyclopropanation enzyme are suitable targets for E. faecalis antibiotic development.
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Velázquez-Sánchez C, Vences-Guzmán MÁ, Moreno S, Tinoco-Valencia R, Espín G, Guzmán J, Sahonero-Canavesi DX, Sohlenkamp C, Segura D. PsrA positively regulates the unsaturated fatty acid synthesis operon fabAB in Azotobacter vinelandii. Microbiol Res 2021; 249:126775. [PMID: 33964629 DOI: 10.1016/j.micres.2021.126775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 03/12/2021] [Accepted: 04/27/2021] [Indexed: 10/21/2022]
Abstract
In Pseudomonas spp. PsrA, a transcriptional activator of the rpoS gene, regulates fatty acid catabolism by repressing the fadBA5 β-oxidation operon. In Azotobacter vinelandii, a soil bacterium closely related to Pseudomonas species, PsrA is also an activator of rpoS expression, although its participation in the regulation of lipid metabolism has not been analyzed. In this work we found that inactivation of psrA had no effect on the expression of β-oxidation genes in this bacterium, but instead decreased expression of the unsaturated fatty acid biosynthetic operon fabAB (3-hydroxydecanoyl-ACP dehydratase/isomerase and 3-ketoacyl-ACP synthase I). This inactivation also reduced the unsaturated fatty acid content, as revealed by the thin-layer chromatographic analysis, and confirmed by gas chromatography; notably, there was also a lower content of cyclopropane fatty acids, which are synthesized from unsaturated fatty acids. The absence of PsrA has no effect on the growth rate, but showed loss of cell viability during long-term growth, in accordance with the role of these unsaturated and cyclopropane fatty acids in the protection of membranes. Finally, an electrophoretic mobility shift assay revealed specific binding of PsrA to the fabA promoter region, where a putative binding site for this regulator was located. Taken together, our data show that PsrA plays an important role in the regulation of unsaturated fatty acids metabolism in A. vinelandii by positively regulating fabAB.
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Affiliation(s)
- Claudia Velázquez-Sánchez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | | | - Soledad Moreno
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Raunel Tinoco-Valencia
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Guadalupe Espín
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Josefina Guzmán
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | | | - Christian Sohlenkamp
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Daniel Segura
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México.
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Jeucken A, Zhou M, Wösten MMSM, Brouwers JF. Control of n-Butanol Induced Lipidome Adaptations in E. coli. Metabolites 2021; 11:metabo11050286. [PMID: 33947169 PMCID: PMC8145963 DOI: 10.3390/metabo11050286] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/21/2021] [Accepted: 04/28/2021] [Indexed: 11/16/2022] Open
Abstract
The versatile compound n-butanol is one of the most promising biofuels for use in existing internal combustion engines, contributing to a smooth transition towards a clean energy society. Furthermore, n-butanol is a valuable resource to produce more complex molecules such as bioplastics. Microbial production of n-butanol from waste materials is hampered by the biotoxicity of n-butanol as it interferes with the proper functioning of lipid membranes. In this study we perform a large-scale investigation of the complete lipid-related enzyme machinery and its response to exposure to a sublethal concentration of n-butanol. We profiled, in triplicate, the growth characteristics and phospholipidomes of 116 different genetic constructs of E. coli, both in the presence and absence of 0.5% n-butanol (v/v). This led to the identification of 230 lipid species and subsequently to the reconstruction of the network of metabolites, enzymes and lipid properties driving the homeostasis of the E. coli lipidome. We were able to identify key lipids and biochemical pathways leading to altered n-butanol tolerance. The data led to new conceptual insights into the bacterial lipid metabolism which are discussed.
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Affiliation(s)
- Aike Jeucken
- Membrane Enzymology, Groningen Biomolecular and Biotechnology Institute (GBB), University of Groningen, 9747 AG Groningen, The Netherlands;
| | - Miaomiao Zhou
- Research Group Analysis Techniques in the Life Sciences, School of Life Sciences and Environmental Technology ATGM, Avans University of Applied Sciences, 4818 AJ Breda, The Netherlands;
| | - Marc M. S. M. Wösten
- Infection Biology, Department of Biomolecular Health Sciences, Utrecht University, 3584 CL Utrecht, The Netherlands;
| | - Jos F. Brouwers
- Research Group Analysis Techniques in the Life Sciences, School of Life Sciences and Environmental Technology ATGM, Avans University of Applied Sciences, 4818 AJ Breda, The Netherlands;
- Center for Molecular Medicine, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
- Correspondence: or
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Santoscoy MC, Jarboe LR. A systematic framework for using membrane metrics for strain engineering. Metab Eng 2021; 66:98-113. [PMID: 33813035 DOI: 10.1016/j.ymben.2021.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 03/14/2021] [Accepted: 03/15/2021] [Indexed: 11/20/2022]
Abstract
The cell membrane plays a central role in the fitness and performance of microbial cell factories and therefore it is an attractive engineering target. The goal of this work is to develop a systematic framework for identifying membrane features for use as engineering targets. The metrics that describe the composition of the membrane can be visualized as "knobs" that modulate various "outcomes", such as physical properties of the membrane and metabolic activity in the form of growth and productivity, with these relationships varying depending on the condition. We generated a set of strains with altered membrane lipid composition via expression of des, fabA and fabB and performed a rigorous characterization of these knobs and outcomes across several individual inhibitory conditions. Here, the knobs are the relative abundance of unsaturated lipids and lipids containing cyclic rings; the average lipid length, and the ratio of linear and non-linear lipids (L/nL ratio). The outcomes are membrane permeability, hydrophobicity, fluidity, and specific growth rate. This characterization identified significant correlations between knobs and outcomes that were specific to individual inhibitors, but also were significant across all tested conditions. For example, across all conditions, the L/nL ratio is positively correlated with the cell surface hydrophobicity, and the average lipid length is positively correlated with specific growth rate. A subsequent analysis of the data with the individual inhibitors identified pairs of lipid metrics and membrane properties that were predicted to impact cell growth in seven modeled scenarios with two or more inhibitors. The L/nL ratio and the membrane hydrophobicity were predicted to impact cell growth with the highest frequency. We experimentally validated this prediction in the combined condition of 42 °C, 2.5 mM furfural and 2% v/v ethanol in minimal media. Membrane hydrophobicity was confirmed to be a significant predictor of ethanol production. This work demonstrates that membrane physical properties can be used to predict the performance of biocatalysts in single and multiple inhibitory conditions, and possibly as an engineering target. In this manner, membrane properties can possibly be used as screening or selection metrics for library- or evolution-based strain engineering.
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Affiliation(s)
- Miguel C Santoscoy
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Laura R Jarboe
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA.
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Schalck T, den Bergh BV, Michiels J. Increasing Solvent Tolerance to Improve Microbial Production of Alcohols, Terpenoids and Aromatics. Microorganisms 2021; 9:249. [PMID: 33530454 PMCID: PMC7912173 DOI: 10.3390/microorganisms9020249] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/14/2021] [Accepted: 01/20/2021] [Indexed: 12/16/2022] Open
Abstract
Fuels and polymer precursors are widely used in daily life and in many industrial processes. Although these compounds are mainly derived from petrol, bacteria and yeast can produce them in an environment-friendly way. However, these molecules exhibit toxic solvent properties and reduce cell viability of the microbial producer which inevitably impedes high product titers. Hence, studying how product accumulation affects microbes and understanding how microbial adaptive responses counteract these harmful defects helps to maximize yields. Here, we specifically focus on the mode of toxicity of industry-relevant alcohols, terpenoids and aromatics and the associated stress-response mechanisms, encountered in several relevant bacterial and yeast producers. In practice, integrating heterologous defense mechanisms, overexpressing native stress responses or triggering multiple protection pathways by modifying the transcription machinery or small RNAs (sRNAs) are suitable strategies to improve solvent tolerance. Therefore, tolerance engineering, in combination with metabolic pathway optimization, shows high potential in developing superior microbial producers.
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Affiliation(s)
- Thomas Schalck
- VIB Center for Microbiology, Flanders Institute for Biotechnology, B-3001 Leuven, Belgium; (T.S.); (B.V.d.B.)
- Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
| | - Bram Van den Bergh
- VIB Center for Microbiology, Flanders Institute for Biotechnology, B-3001 Leuven, Belgium; (T.S.); (B.V.d.B.)
- Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
| | - Jan Michiels
- VIB Center for Microbiology, Flanders Institute for Biotechnology, B-3001 Leuven, Belgium; (T.S.); (B.V.d.B.)
- Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
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Blitzblau HG, Consiglio AL, Teixeira P, Crabtree DV, Chen S, Konzock O, Chifamba G, Su A, Kamineni A, MacEwen K, Hamilton M, Tsakraklides V, Nielsen J, Siewers V, Shaw AJ. Production of 10-methyl branched fatty acids in yeast. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:12. [PMID: 33413611 PMCID: PMC7791843 DOI: 10.1186/s13068-020-01863-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 12/17/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND Despite the environmental value of biobased lubricants, they account for less than 2% of global lubricant use due to poor thermo-oxidative stability arising from the presence of unsaturated double bonds. Methyl branched fatty acids (BFAs), particularly those with branching near the acyl-chain mid-point, are a high-performance alternative to existing vegetable oils because of their low melting temperature and full saturation. RESULTS We cloned and characterized two pathways to produce 10-methyl BFAs isolated from actinomycetes and γ-proteobacteria. In the two-step bfa pathway of actinomycetes, BfaB methylates Δ9 unsaturated fatty acids to form 10-methylene BFAs, and subsequently, BfaA reduces the double bond to produce a fully saturated 10-methyl branched fatty acid. A BfaA-B fusion enzyme increased the conversion efficiency of 10-methyl BFAs. The ten-methyl palmitate production (tmp) pathway of γ-proteobacteria produces a 10-methylene intermediate, but the TmpA putative reductase was not active in E. coli or yeast. Comparison of BfaB and TmpB activities revealed a range of substrate specificities from C14-C20 fatty acids unsaturated at the Δ9, Δ10 or Δ11 position. We demonstrated efficient production of 10-methylene and 10-methyl BFAs in S. cerevisiae by secretion of free fatty acids and in Y. lipolytica as triacylglycerides, which accumulated to levels more than 35% of total cellular fatty acids. CONCLUSIONS We report here the characterization of a set of enzymes that can produce position-specific methylene and methyl branched fatty acids. Yeast expression of bfa enzymes can provide a platform for the large-scale production of branched fatty acids suitable for industrial and consumer applications.
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Affiliation(s)
- Hannah G Blitzblau
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA.
- Ginkgo BioWorks, 27 Drydock Ave., Boston, MA, 02210, USA.
| | - Andrew L Consiglio
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
- Ginkgo BioWorks, 27 Drydock Ave., Boston, MA, 02210, USA
| | - Paulo Teixeira
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden
| | | | - Shuyan Chen
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
- Ginkgo BioWorks, 27 Drydock Ave., Boston, MA, 02210, USA
| | - Oliver Konzock
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden
| | - Gamuchirai Chifamba
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
- Ginkgo BioWorks, 27 Drydock Ave., Boston, MA, 02210, USA
| | - Austin Su
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
| | - Annapurna Kamineni
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
- Ginkgo BioWorks, 27 Drydock Ave., Boston, MA, 02210, USA
| | - Kyle MacEwen
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
- Ginkgo BioWorks, 27 Drydock Ave., Boston, MA, 02210, USA
| | - Maureen Hamilton
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
- Ginkgo BioWorks, 27 Drydock Ave., Boston, MA, 02210, USA
| | - Vasiliki Tsakraklides
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
- Ginkgo BioWorks, 27 Drydock Ave., Boston, MA, 02210, USA
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden
- BioInnovation Institute, Ole Maaløes Vej 3, 2200, Copenhagen N, Denmark
| | - Verena Siewers
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden
| | - A Joe Shaw
- Novogy, Inc., 85 Bolton Street, Cambridge, MA, 02140, USA
- Manus Biosynthesis, 1030 Massachusetts Ave. #300, Cambridge, MA, 02138, USA
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Lee TH, Hofferek V, Sani MA, Separovic F, Reid GE, Aguilar MI. The impact of antibacterial peptides on bacterial lipid membranes depends on stage of growth. Faraday Discuss 2021; 232:399-418. [DOI: 10.1039/d0fd00052c] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Impact of maculatin 1.1 on supported lipid bilayers (SLBs) derived from early growth phase (EGP) or stationary growth phase (SGP) E. coli lipid extracts, monitored by atomic force microscopy which images bilayer morphology in real time.
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Affiliation(s)
- Tzong-Hsien Lee
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Vinzenz Hofferek
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3010, Australia
| | - Marc-Antoine Sani
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3010, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3010, Australia
| | - Gavin E. Reid
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3010, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
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Shi YG, Zhang RR, Zhu CM, Xu MF, Gu Q, Ettelaie R, Lin S, Wang YF, Leng XY. Antimicrobial mechanism of alkyl gallates against Escherichia coli and Staphylococcus aureus and its combined effect with electrospun nanofibers on Chinese Taihu icefish preservation. Food Chem 2020; 346:128949. [PMID: 33418419 DOI: 10.1016/j.foodchem.2020.128949] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 11/29/2020] [Accepted: 12/22/2020] [Indexed: 01/17/2023]
Abstract
The objective of this study was to investigate the antibacterial activity and potential mechanism of alkyl gallates against Escherichia coli and Staphylococcus aureus. Results show that the length of the alkyl chain plays a pivotal role in eliciting the activity and octyl gallate (OG) exerted excellent bactericidal activity through a multiple bactericidal mechanism. OG functions against both bacteria through damaging bacterial cell wall integrity, permeating into cells and then interacting with DNA, as well as disturbing the activity of the respiratory electron transport chain to induce a high-level toxic ROS (hydroxyl radicals) generation and up-regulation of the ROS genes. Also, electrospun nanofibers with OG have unique superiorities for maintaining the freshness of the icefish (4 °C). This research not only provides a more in-depth understanding of the interaction between OG and microorganisms but also highlights the great promise of using OG as a safe multi-functionalized food additive for food preservations.
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Affiliation(s)
- Yu-Gang Shi
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China; Key Laboratory for Food Microbial Technology of Zhejiang Province, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China.
| | - Run-Run Zhang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China
| | - Chen-Min Zhu
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China
| | - Ming-Feng Xu
- Key Laboratory for Quality and Safety of Agricultural Products of Hangzhou, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Qing Gu
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China; Key Laboratory for Food Microbial Technology of Zhejiang Province, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China
| | - Rammile Ettelaie
- School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK
| | - Shan Lin
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China
| | - Yi-Fan Wang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China
| | - Xin-Yi Leng
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang 310035, China
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Effects of a Δ-9-fatty acid desaturase and a cyclopropane-fatty acid synthase from the novel psychrophile Pseudomonas sp. B14-6 on bacterial membrane properties. J Ind Microbiol Biotechnol 2020; 47:1045-1057. [PMID: 33259029 DOI: 10.1007/s10295-020-02333-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 11/17/2020] [Indexed: 10/22/2022]
Abstract
Psychrophilic bacteria, living at low and mild temperatures, can contribute significantly to our understanding of microbial responses to temperature, markedly occurring in the bacterial membrane. Here, a newly isolated strain, Pseudomonas sp. B14-6, was found to dynamically change its unsaturated fatty acid and cyclic fatty acid content depending on temperature which was revealed by phospholipid fatty acid (PLFA) analysis. Genome sequencing yielded the sequences of the genes Δ-9-fatty acid desaturase (desA) and cyclopropane-fatty acid-acyl-phospholipid synthase (cfa). Overexpression of desA in Escherichia coli led to an increase in the levels of unsaturated fatty acids, resulting in decreased membrane hydrophobicity and increased fluidity. Cfa proteins from different species were all found to promote bacterial growth, despite their sequence diversity. In conclusion, PLFA analysis and genome sequencing unraveled the temperature-related behavior of Pseudomonas sp. B14-6 and the functions of two membrane-related enzymes. Our results shed new light on temperature-dependent microbial behaviors and might allow to predict the consequences of global warming on microbial communities.
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Arcari T, Feger ML, Guerreiro DN, Wu J, O’Byrne CP. Comparative Review of the Responses of Listeria monocytogenes and Escherichia coli to Low pH Stress. Genes (Basel) 2020; 11:genes11111330. [PMID: 33187233 PMCID: PMC7698193 DOI: 10.3390/genes11111330] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/03/2020] [Accepted: 11/09/2020] [Indexed: 02/07/2023] Open
Abstract
Acidity is one of the principal physicochemical factors that influence the behavior of microorganisms in any environment, and their response to it often determines their ability to grow and survive. Preventing the growth and survival of pathogenic bacteria or, conversely, promoting the growth of bacteria that are useful (in biotechnology and food production, for example), might be improved considerably by a deeper understanding of the protective responses that these microorganisms deploy in the face of acid stress. In this review, we survey the molecular mechanisms used by two unrelated bacterial species in their response to low pH stress. We chose to focus on two well-studied bacteria, Escherichia coli (phylum Proteobacteria) and Listeria monocytogenes (phylum Firmicutes), that have both evolved to be able to survive in the mammalian gastrointestinal tract. We review the mechanisms that these species use to maintain a functional intracellular pH as well as the protective mechanisms that they deploy to prevent acid damage to macromolecules in the cells. We discuss the mechanisms used to sense acid in the environment and the regulatory processes that are activated when acid is encountered. We also highlight the specific challenges presented by organic acids. Common themes emerge from this comparison as well as unique strategies that each species uses to cope with acid stress. We highlight some of the important research questions that still need to be addressed in this fascinating field.
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Lolli V, Dall’Asta M, Del Rio D, Caligiani A. Identification of Cyclopropane Fatty Acids in Human Plasma after Controlled Dietary Intake of Specific Foods. Nutrients 2020; 12:nu12113347. [PMID: 33143177 PMCID: PMC7693023 DOI: 10.3390/nu12113347] [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: 10/14/2020] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 11/21/2022] Open
Abstract
Cyclopropane fatty acids (CPFAs) are an investigated class of secondary fatty acids of microbial origin recently identified in foods. Even though the dietary daily intake of this class of compounds it has been recently estimated as not negligible, to date, no studies specifically have investigated their presence in human plasma after consumption of CPFA-rich sources. Therefore, the aims of this study were (i) to test CPFAs concentration in human plasma, thus demonstrating their in vivo bioaccessibility and potential bioavailability, (ii) to investigate a dose-response relationship between medium term chronic intake of CPFAs-rich foods and both CPFAs and plasma total fatty acid profiles in healthy subjects. Ten healthy normal weight adults were enrolled for conducting an in vivo study. Participants were asked to follow a CPFA-controlled diet for 3 weeks, consuming 50 g of Grana Padano cheese (GP) and 250 mL of whole cow milk, which correspond to a total of 22.1 mg of CPFAs. Fasting CPFAs concentration were monitored for eight timepoints during the whole study and plasma total fatty acids composition was determined by GC-MS. CPFAs, mainly dihydrosterculic acid (DHSA), were identified in plasma total fatty acids profile at the beginning of the study and after dietary treatment. A significant (p < 0.05) increase of CPFAs mean plasma concentration (n = 10) were observed at the end of the dietary intervention. Contrarily, the total fatty acids composition of the general plasma fatty acids profile did not significantly change (p ≥ 0.05) during the dietary intervention period. This is the first investigation demonstrating that CPFAs are bioaccessible in vivo and, as expected, their plasmatic concentration may be affected by consumption of CPFAs-rich foods. This research will open the door to further detailed research, which may better elucidate the role of these compounds in human health.
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Affiliation(s)
- Veronica Lolli
- Department of Food and Drug, University of Parma, 43124 Parma, Italy; (V.L.); (A.C.)
| | - Margherita Dall’Asta
- Department of Animal Science, Food and Nutrition, Università Cattolica del Sacro Cuore, 29122 Piacenza, Italy
- Correspondence:
| | - Daniele Del Rio
- Department of Veterinary Science, University of Parma, 43126 Parma, Italy;
- School of Advanced Studies on Food and Nutrition, University of Parma, 43124 Parma, Italy
| | - Augusta Caligiani
- Department of Food and Drug, University of Parma, 43124 Parma, Italy; (V.L.); (A.C.)
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46
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Rahman APH, Dash S, Mohanty PS, Mishra A, Lundborg CS, Tripathy SK. Sonophotocatalytic disinfection of Shigella species under visible light irradiation: Insights into its molecular mechanism, antibacterial resistance and biofilm formation. ENVIRONMENTAL RESEARCH 2020; 187:109620. [PMID: 32416355 DOI: 10.1016/j.envres.2020.109620] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 04/25/2020] [Accepted: 04/30/2020] [Indexed: 06/11/2023]
Abstract
Microbial contamination of water is one of the major sources of many diseases worldwide. Evolution of antibacterial resistance (ABR) alongside the caveats in most of the water treatment methods causes the severity of the current problem extremely vexing. This calls for an urgent need to develop new treatment methods aiming to reduce the microbial as well as ABR load in the environment. Herein, we successfully developed a visible light assisted sonophotocatalysis (SPC) using Fe/ZnO nanoparticles (NPs) for the disinfection of Shigella dysenteriae. A consortia containing S. dysenteriae and S. flexineri was also completely disinfected using SPC. Growth conditions of S. dysenteriae like growth phases and growth temperaturehad different outcomes on the overall efficacy of SPC. Compared with catalysts such as ZnO and TiO2, Fe/ZnO resulted in better disinfection. Multi-ROS production, mostly containing h+ and O2· radicals, due to the electron displacement in the catalyst and acoustic cavitation was identified as the factors behind bacterial lethality. The ROS produced was found to interfere with the metabolic activities of S. dysenteriae by causing membrane perturbation. We identified DNA damage inside the cells and the subsequent release of intracellular components. The compositional changes in the fatty acid makeup of the cells were altered as a result of SPC and few fatty acid markers indicating the stress posed by SPC were also identified. Loss of ABR in S. dysenteriae was also recorded post SPC treatment. Abatement in the biofilm forming ability of the injured bacterial cells was also recorded, proving the extremity of stress induced by SPC. Hence, the excellent efficacy of SPC in disinfecting bacteria is proposed for tertiary water treatment applications.
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Affiliation(s)
- A P Habeeb Rahman
- School of Chemical Technology, Kalinga Institute of Industrial Technology, Bhubaneswar, 751024, Odisha, India; School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, 751024, Odisha, India
| | - Swagatika Dash
- School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, 751024, Odisha, India
| | - Priti Sundar Mohanty
- School of Chemical Technology, Kalinga Institute of Industrial Technology, Bhubaneswar, 751024, Odisha, India
| | - Amrita Mishra
- School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, 751024, Odisha, India
| | | | - Suraj K Tripathy
- School of Chemical Technology, Kalinga Institute of Industrial Technology, Bhubaneswar, 751024, Odisha, India; School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, 751024, Odisha, India.
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47
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Cao X, Brouwers JFHM, van Dijk L, van de Lest CHA, Parker CT, Huynh S, van Putten JPM, Kelly DJ, Wösten MMSM. The Unique Phospholipidome of the Enteric Pathogen Campylobacter jejuni: Lysophosholipids Are Required for Motility at Low Oxygen Availability. J Mol Biol 2020; 432:5244-5258. [PMID: 32710984 DOI: 10.1016/j.jmb.2020.07.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/14/2020] [Accepted: 07/20/2020] [Indexed: 12/21/2022]
Abstract
In response to changes in their environment bacteria need to change both their protein and phospholipid repertoire to match environmental requirements, but the dynamics of bacterial phospholipid composition under different growth conditions is still largely unknown. In the present study, we investigated the phospholipidome of the bacterial pathogen Campylobacter jejuni. Transcription profiling on logarithmic and stationary phase grown cells of the microaerophilic human pathogen C. jejuni using RNA-seq revealed differential expression of putative phospholipid biosynthesis genes. By applying high-performance liquid chromatography tandem-mass spectrometry, we identified 203 phospholipid species representing the first determination of the phospholipidome of this pathogen. We identified nine different phospholipid classes carrying between one and three acyl chains. Phospholipidome analysis on bacteria of different ages (0-5 days) showed rapid changes in the ratio of phospholipids containing ethanolamine, or glycerol as phospholipid head group and in the number of cyclopropane bond containing fatty acids. Oxygen concentration influenced the percentage of lysophospholipids, and cyclo-propane bonds containing acyl chains. We show that large amounts of the phospholipids are lysophospholipids (30-45%), which mutant studies reveal are needed for normal C. jejuni motility at low oxygen conditions. C. jejuni possesses an unusual phospholipidome that is highly dynamic in response to environmental changes.
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Affiliation(s)
- Xuefeng Cao
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, the Netherlands
| | - Jos F H M Brouwers
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, the Netherlands
| | - Linda van Dijk
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, the Netherlands
| | - Chris H A van de Lest
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, the Netherlands
| | - Craig T Parker
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA 94710, USA
| | - Steven Huynh
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA 94710, USA
| | - Jos P M van Putten
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, the Netherlands
| | - David J Kelly
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Marc M S M Wösten
- Department Biomolecular Health Sciences, Utrecht University, Utrecht, the Netherlands.
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Blevins MS, James VK, Herrera CM, Purcell AB, Trent MS, Brodbelt JS. Unsaturation Elements and Other Modifications of Phospholipids in Bacteria: New Insight from Ultraviolet Photodissociation Mass Spectrometry. Anal Chem 2020; 92:9146-9155. [PMID: 32479092 PMCID: PMC7384744 DOI: 10.1021/acs.analchem.0c01449] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Glycerophospholipids (GPLs), one of the main components of bacterial cell membranes, exhibit high levels of structural complexity that are directly correlated with biophysical membrane properties such as permeability and fluidity. This structural complexity arises from the substantial variability in the individual GPL structural components such as the acyl chain length and headgroup type and is further amplified by the presence of modifications such as double bonds and cyclopropane rings. Here we use liquid chromatography coupled to high-resolution and high-mass-accuracy ultraviolet photodissociation mass spectrometry for the most in-depth study of bacterial GPL modifications to date. In doing so, we unravel a diverse array of unexplored GPL modifications, ranging from acyl chain hydroxyl groups to novel headgroup structures. Along with characterizing these modifications, we elucidate general trends in bacterial GPL unsaturation elements and thus aim to decipher some of the biochemical pathways of unsaturation incorporation in bacterial GPLs. Finally, we discover aminoacyl-PGs not only in Gram-positive bacteria but also in Gram-negative C. jejuni, advancing our knowledge of the methods of surface charge modulation that Gram-negative organisms may adopt for antibiotic resistance.
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Affiliation(s)
- Molly S Blevins
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Virginia K James
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Carmen M Herrera
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602, United States
| | - Alexandria B Purcell
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602, United States
| | - M Stephen Trent
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602, United States
- Department of Microbiology, College of Arts and Sciences, University of Georgia, Athens, Georgia 30602, United States
- Center for Vaccines and Immunology, University of Georgia, Athens, Georgia 30602, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
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Palyzová A, Marešová H, Novák J, Zahradník J, Řezanka T. Effect of the anti-inflammatory drug diclofenac on lipid composition of bacterial strain Raoultella sp. KDF8. Folia Microbiol (Praha) 2020; 65:763-773. [PMID: 32318987 DOI: 10.1007/s12223-020-00790-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 04/08/2020] [Indexed: 01/18/2023]
Abstract
The strain Raoultella sp. KDF8 was cultivated on three sources of carbon and energy, glycerol, ethanol and diclofenac, for periods of time ranging from 24 to 72 h. Using thin-layer chromatography, nine classes of phospholipids were detected and the amount of phosphatidylethanolamine (PtdEtn) decreased with increasing cultivation time. Conversely, the ratio of phospholipids having three or four acyls (acyl-phosphatidylglycerol (APtdGro), N-acyl-PtdEtn (NAPtdEtn) and cardiolipin (Ptd2Gro) increased during cultivation. GC-MS analysis showed that the percentage of fatty acids containing a cyclopropane ring increased almost tenfold whereas the amount of fatty acids bearing even-numbered chains dropped to less than one-third after 24 h and 72 h in cultures on glycerol and diclofenac, respectively. Shotgun analysis showed significant changes in the representation of molecular species of phospholipids. For instance, there was a 36-fold change in the ratio of 16:1/16:1/16:1-APtdGro to c17:0/c17:0/c17:0-APtdGro and a 12-fold ratio change for 16:1/16:1/16:1-NAPtdEtn to c17:0/c17:0/c17:0-NAPtdEtn; the Ptd2Gro ratio of 16:1 to c17:0 acids equalled 1750. Our results show that the bacteria overcome destabilization of the inner cytoplasmic cell membrane and a bacterial outer membrane by altering the geometric arrangement of acyl chains, i.e. switching from monounsaturated to cyclopropane fatty acids (16:1 versus c17:0).
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Affiliation(s)
- Andrea Palyzová
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Helena Marešová
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Jiří Novák
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Jiří Zahradník
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Tomáš Řezanka
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic.
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50
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Recent applications of mass spectrometry in bacterial lipidomics. Anal Bioanal Chem 2020; 412:5935-5943. [DOI: 10.1007/s00216-020-02541-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/14/2020] [Accepted: 02/21/2020] [Indexed: 12/11/2022]
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