1
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Barbotin A, Billaudeau C, Sezgin E, Carballido-López R. Quantification of membrane fluidity in bacteria using TIR-FCS. Biophys J 2024; 123:2484-2495. [PMID: 38877702 PMCID: PMC11365102 DOI: 10.1016/j.bpj.2024.06.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 05/28/2024] [Accepted: 06/10/2024] [Indexed: 06/16/2024] Open
Abstract
Plasma membrane fluidity is an important phenotypic feature that regulates the diffusion, function, and folding of transmembrane and membrane-associated proteins. In bacterial cells, variations in membrane fluidity are known to affect respiration, transport, and antibiotic resistance. Membrane fluidity must therefore be tightly regulated to adapt to environmental variations and stresses such as temperature fluctuations or osmotic shocks. Quantitative investigation of bacterial membrane fluidity has been, however, limited due to the lack of available tools, primarily due to the small size and membrane curvature of bacteria that preclude most conventional analysis methods used in eukaryotes. Here, we develop an assay based on total internal reflection-fluorescence correlation spectroscopy (TIR-FCS) to directly measure membrane fluidity in live bacteria via the diffusivity of fluorescent membrane markers. With simulations validated by experiments, we could determine how the small size, high curvature, and geometry of bacteria affect diffusion measurements and correct subsequent measurements for unbiased diffusion coefficient estimation. We used this assay to quantify the fluidity of the cytoplasmic membranes of the Gram-positive bacteria Bacillus subtilis (rod-shaped) and Staphylococcus aureus (coccus) at high (37°C) and low (20°C) temperatures in a steady state and in response to a cold shock, caused by a shift from high to low temperature. The steady-state fluidity was lower at 20°C than at 37°C, yet differed between B. subtilis and S. aureus at 37°C. Upon cold shock, the membrane fluidity decreased further below the steady-state fluidity at 20°C and recovered within 30 min in both bacterial species. Our minimally invasive assay opens up exciting perspectives for the study of a wide range of phenomena affecting the bacterial membrane, from disruption by chemicals or antibiotics to viral infection or change in nutrient availability.
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Affiliation(s)
- Aurélien Barbotin
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France.
| | - Cyrille Billaudeau
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Erdinc Sezgin
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Rut Carballido-López
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France.
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2
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Barbarek SC, Shah R, Paul S, Alvarado G, Appala K, Phillips C, Henderson EC, Strandquist ET, Pokorny A, Singh VK, Gatto C, Dahl JU, Hines KM, Wilkinson BJ. Lipidomics of homeoviscous adaptation to low temperatures in Staphylococcus aureus utilizing exogenous straight-chain unsaturated fatty acids. J Bacteriol 2024; 206:e0018724. [PMID: 38953643 PMCID: PMC11270863 DOI: 10.1128/jb.00187-24] [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: 05/16/2024] [Accepted: 06/09/2024] [Indexed: 07/04/2024] Open
Abstract
It is well established that Staphylococcus aureus can incorporate exogenous straight-chain unsaturated fatty acids (SCUFAs) into membrane phospho- and glyco-lipids from various sources in supplemented culture media and when growing in vivo during infection. Given the enhancement of membrane fluidity when oleic acid (C18:1Δ9) is incorporated into lipids, we were prompted to examine the effect of medium supplementation with C18:1Δ9 on growth at low temperatures. C18:1Δ9 supported the growth of a cold-sensitive, branched-chain fatty acid (BCFA)-deficient mutant at 12°C. Interestingly, we found similar results in the BCFA-sufficient parental strain, supported by the fact that the incorporation of C18:1Δ9 into the membrane increased membrane fluidity in both strains. We show that the incorporation of C18:1Δ9 and its elongation product C20:1Δ11 into membrane lipids was required for growth stimulation and relied on a functional FakAB incorporation system. Lipidomics analysis of the phosphatidylglycerol and diglycosyldiacylglycerol lipid classes revealed major impacts of C18:1Δ9 and temperature on lipid species. Growth at 12°C in the presence of C18:1Δ9 also led to increased production of the carotenoid pigment staphyloxanthin. The enhancement of growth by C18:1Δ9 is an example of homeoviscous adaptation to low temperatures utilizing an exogenous fatty acid. This may be significant in the growth of S. aureus at low temperatures in foods that commonly contain C18:1Δ9 and other SCUFAs in various forms. IMPORTANCE We show that Staphylococcus aureus can use its known ability to incorporate exogenous fatty acids to enhance its growth at low temperatures. Individual species of phosphatidylglycerols and diglycosyldiacylglycerols bearing one or two degrees of unsaturation derived from the incorporation of C18:1Δ9 at 12°C are described for the first time. In addition, enhanced production of the carotenoid staphyloxanthin occurs at low temperatures. The studies describe a biochemical reality underlying membrane biophysics. This is an example of homeoviscous adaptation to low temperatures utilizing exogenous fatty acids over the regulation of the biosynthesis of endogenous fatty acids. The studies have likely relevance to food safety in that unsaturated fatty acids may enhance the growth of S. aureus in the food environment.
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Affiliation(s)
- Shannon C. Barbarek
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Ritika Shah
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Sharanya Paul
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Gloria Alvarado
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Keerthi Appala
- Department of Chemistry, University of Georgia, Athens, Georgia, USA
| | - Caiden Phillips
- Department of Microbiology and Immunology, Kirksville College of Osteopathic Medicine, A. T. Still University of Health Sciences, Kirksville, Missouri, USA
| | - Emma C. Henderson
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Evan T. Strandquist
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Antje Pokorny
- Department of Chemistry and Biochemistry, University of North Carolina-Wilmington, Wilmington, North Carolina, USA
| | - Vineet K. Singh
- Department of Microbiology and Immunology, Kirksville College of Osteopathic Medicine, A. T. Still University of Health Sciences, Kirksville, Missouri, USA
| | - Craig Gatto
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Jan-Ulrik Dahl
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Kelly M. Hines
- Department of Chemistry, University of Georgia, Athens, Georgia, USA
| | - Brian J. Wilkinson
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
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3
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Barbarek SC, Shah R, Paul S, Alvarado G, Appala K, Henderson EC, Strandquist ET, Pokorny A, Singh VK, Gatto C, Dahl JU, Hines KM, Wilkinson BJ. Lipidomics of homeoviscous adaptation to low temperatures in Staphylococcus aureus utilizing exogenous straight-chain unsaturated fatty acids over biosynthesized endogenous branched-chain fatty acids. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.02.578686. [PMID: 38352554 PMCID: PMC10862916 DOI: 10.1101/2024.02.02.578686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
It is well established that Staphylococcus aureus can incorporate exogenous straight-chain unsaturated fatty acids (SCUFAs) into membrane phospho- and glyco-lipids from various sources in supplemented culture media, and when growing in vivo in an infection. Given the enhancement of membrane fluidity when oleic acid (C18:1Δ9) is incorporated into lipids, we were prompted to examine the effect of medium supplementation with C18:1Δ9 on growth at low temperatures. C18:1Δ9 supported the growth of a cold-sensitive, branched-chain fatty acid (BCFA)-deficient mutant at 12°C. Interestingly, we found similar results in the BCFA-sufficient parental strain. We show that incorporation of C18:1Δ9 and its elongation product C20:1Δ9 into membrane lipids was required for growth stimulation and relied on a functional FakAB incorporation system. Lipidomics analysis of the phosphatidylglycerol (PG) and diglycosyldiacylglycerol (DGDG) lipid classes revealed major impacts of C18:1Δ9 and temperature on lipid species. Growth at 12°C in the presence of C18:1Δ9 also led to increased production of the carotenoid pigment staphyloxanthin; however, this was not an obligatory requirement for cold adaptation. Enhancement of growth by C18:1Δ9 is an example of homeoviscous adaptation to low temperatures utilizing an exogenous fatty acid. This may be significant in the growth of S. aureus at low temperatures in foods that commonly contain C18:1Δ9 and other SCUFAs in various forms.
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Affiliation(s)
| | - Ritika Shah
- School of Biological Sciences, Illinois State University, Normal, IL
| | - Sharanya Paul
- School of Biological Sciences, Illinois State University, Normal, IL
| | - Gloria Alvarado
- School of Biological Sciences, Illinois State University, Normal, IL
| | - Keerthi Appala
- Department of Chemistry, University of Georgia, Athens, GA
| | - Emma C. Henderson
- School of Biological Sciences, Illinois State University, Normal, IL
| | | | - Antje Pokorny
- Department of Chemistry and Biochemistry, University of North Carolina-Wilmington, Wilmington, NC
| | - Vineet K. Singh
- Department of Microbiology and Immunology, Kirksville College of Osteopathic Medicine, A. T. Still University of Health Sciences, Kirksville, MO
| | - Craig Gatto
- School of Biological Sciences, Illinois State University, Normal, IL
| | - Jan-Ulrik Dahl
- School of Biological Sciences, Illinois State University, Normal, IL
| | - Kelly M. Hines
- Department of Chemistry, University of Georgia, Athens, GA
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4
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Itoh H, Inoue M. Development of a High-Throughput Strategy for Functional Enhancement and Alteration of Antibacterial Natural Products. J SYN ORG CHEM JPN 2021. [DOI: 10.5059/yukigoseikyokaishi.79.996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - Masayuki Inoue
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
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5
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Development of a high-throughput strategy for discovery of potent analogues of antibiotic lysocin E. Nat Commun 2019; 10:2992. [PMID: 31278250 PMCID: PMC6611794 DOI: 10.1038/s41467-019-10754-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 05/30/2019] [Indexed: 12/13/2022] Open
Abstract
Lysocin E, a 37-membered natural depsipeptide, induces rapid bacteriolysis in methicillin-resistant Staphylococcus aureus via a unique menaquinone-dependent mechanism, presenting a promising therapeutic lead. Despite the great medical importance, exploring the potential utility of its derivatives as new platform structures for antibiotic development has remained a significant challenge. Here, we report a high-throughput strategy that enabled the preparation of thousands of analogues of lysocin E and large-scale structure-activity relationship analyses. We integrate 26-step total synthesis of 2401 cyclic peptides, tandem mass spectrometry-sequencing, and two microscale activity assays to identify 23 candidate compounds. Re-synthesis of these candidates shows that 11 of them (A1-A11) exhibit antimicrobial activity superior or comparable to that of lysocin E, and that lysocin E and A1-A11 share L-Leu-6 and L-Ile-11. Therefore, the present strategy allows us to efficiently decipher biologically crucial residues and identify potentially useful agents for the treatment of infectious diseases.
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6
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Gaglione R, Cesaro A, Dell'Olmo E, Della Ventura B, Casillo A, Di Girolamo R, Velotta R, Notomista E, Veldhuizen EJA, Corsaro MM, De Rosa C, Arciello A. Effects of human antimicrobial cryptides identified in apolipoprotein B depend on specific features of bacterial strains. Sci Rep 2019; 9:6728. [PMID: 31040323 PMCID: PMC6491590 DOI: 10.1038/s41598-019-43063-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 04/12/2019] [Indexed: 12/03/2022] Open
Abstract
Cationic Host Defense Peptides (HDPs) are endowed with a broad variety of activities, including direct antimicrobial properties and modulatory roles in the innate immune response. Even if it has been widely demonstrated that bacterial membrane represents the main target of peptide antimicrobial activity, the molecular mechanisms underlying membrane perturbation by HDPs have not been fully clarified yet. Recently, two cryptic HDPs have been identified in human apolipoprotein B and found to be endowed with a broad-spectrum antimicrobial activity, and with anti-biofilm, wound healing and immunomodulatory properties. Moreover, ApoB derived HDPs are able to synergistically act in combination with conventional antibiotics, while being not toxic for eukaryotic cells. Here, by using a multidisciplinary approach, including time killing curves, Zeta potential measurements, membrane permeabilization assays, electron microscopy analyses, and isothermal titration calorimetry studies, the antimicrobial effects of ApoB cryptides have been analysed on bacterial strains either susceptible or resistant to peptide toxicity. Intriguingly, it emerged that even if electrostatic interactions between negatively charged bacterial membranes and positively charged HDPs play a key role in mediating peptide toxicity, they are strongly influenced by the composition of negatively charged bacterial surfaces and by defined extracellular microenvironments.
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Affiliation(s)
- Rosa Gaglione
- Department of Chemical Sciences, University of Naples Federico II, 80126, Naples, Italy
| | - Angela Cesaro
- Department of Chemical Sciences, University of Naples Federico II, 80126, Naples, Italy
| | - Eliana Dell'Olmo
- Department of Chemical Sciences, University of Naples Federico II, 80126, Naples, Italy
| | | | - Angela Casillo
- Department of Chemical Sciences, University of Naples Federico II, 80126, Naples, Italy
| | - Rocco Di Girolamo
- Department of Chemical Sciences, University of Naples Federico II, 80126, Naples, Italy
| | - Raffaele Velotta
- Department of Physics, University of Naples Federico II, 80126, Naples, Italy
| | - Eugenio Notomista
- Department of Biology, University of Naples Federico II, 80126, Naples, Italy
| | - Edwin J A Veldhuizen
- Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Maria Michela Corsaro
- Department of Chemical Sciences, University of Naples Federico II, 80126, Naples, Italy
| | - Claudio De Rosa
- Department of Chemical Sciences, University of Naples Federico II, 80126, Naples, Italy
| | - Angela Arciello
- Department of Chemical Sciences, University of Naples Federico II, 80126, Naples, Italy. .,Istituto Nazionale di Biostrutture e Biosistemi (INBB), Rome, Italy.
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7
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Perez-Lopez MI, Mendez-Reina R, Trier S, Herrfurth C, Feussner I, Bernal A, Forero-Shelton M, Leidy C. Variations in carotenoid content and acyl chain composition in exponential, stationary and biofilm states of Staphylococcus aureus, and their influence on membrane biophysical properties. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:978-987. [PMID: 30771288 DOI: 10.1016/j.bbamem.2019.02.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 01/01/2023]
Abstract
Bacteria are often found in close association with surfaces, resulting in the formation of biofilms. In Staphylococcus aureus (S. aureus), biofilms are implicated in the resilience of chronic infections, presenting a serious clinical problem world-wide. Here, S. aureus biofilms are grown under flow within clinical catheters at 37 °C. The lipid composition and biophysical properties of lipid extracts from these biofilms are compared with those from exponential growth and stationary phase cells. Biofilms show a reduction in iso and anteiso branching compensated by an increase in saturated fatty acids compared to stationary phase. A drastic reduction in carotenoid levels is also observed during biofilm formation. Thermotropic measurements of Laurdan GP and DPH polarization, show a reduction of lipid packing at 37 °C for biofilms compared to stationary phase. We studied the effects of carotenoid content on DMPG and DPPG model membranes showing trends in thermotropic behavior consistent with those observed in bacterial isolates, indicating that carotenoids participate in modulating lipid packing. Additionally, bending elastic constant (kc) measurements using vesicle fluctuation analysis (VFA) show that the presence of carotenoids can increase membrane bending rigidity. The antimicrobial peptide Magainin H2 was less activity on liposomes composed of stationary phase compared to biofilms or exponential growth isolates. This study contributes to an understanding of how Staphylococcus aureus modulates the composition of its membrane lipids, and how those changes affect the biophysical properties of membranes, which in turn may play a role in its virulence and its resistance to different membrane-active antimicrobial agents.
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Affiliation(s)
- Maria Isabel Perez-Lopez
- Department of Physics, Universidad de los Andes, Bogotá, Colombia; Biological Sciences Department, Universidad de los Andes, Bogotá, Colombia
| | | | - Steve Trier
- Department of Physics, Universidad de los Andes, Bogotá, Colombia
| | - Cornelia Herrfurth
- Department of Plant Biochemistry, Albrecht-von-Haller Institute for Plant Sciences, University of Goettingen, Goettingen, Germany
| | - Ivo Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller Institute for Plant Sciences, University of Goettingen, Goettingen, Germany; Department of Plant Biochemistry, Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goettingen, Germany
| | - Adriana Bernal
- Biological Sciences Department, Universidad de los Andes, Bogotá, Colombia
| | | | - Chad Leidy
- Department of Physics, Universidad de los Andes, Bogotá, Colombia.
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8
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Effect of interactions of plant phenolics with bovine meat proteins on their antibacterial activity. Food Control 2018. [DOI: 10.1016/j.foodcont.2018.03.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Effect of Polyvalence on the Antibacterial Activity of a Synthetic Peptide Derived from Bovine Lactoferricin against Healthcare-Associated Infectious Pathogens. BIOMED RESEARCH INTERNATIONAL 2018; 2018:5252891. [PMID: 29984236 PMCID: PMC6015718 DOI: 10.1155/2018/5252891] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/07/2018] [Accepted: 04/11/2018] [Indexed: 11/29/2022]
Abstract
Antimicrobial peptides (AMPs) are gaining interest as potential therapeutic agents. Peptides derived from bovine lactoferricin B (LfcinB) have been reported to exhibit antimicrobial activity, and the LfcinB RRWQWR sequence is the smallest known motif that exhibits antibacterial and cytotoxic activity. Our goal was to examine the effect of multicopy arrangements of the RRWQWR motif, on its antibacterial activity against healthcare-associated infections (HCAIs). Linear and branched peptides containing the RRWQWR motif were generated using solid phase peptide synthesis-Fmoc/tBu methodology, purified, and characterized using reverse phase-high performance liquid chromatography and matrix-assisted laser desorption/ionization time of flight mass spectrometry. For each peptide, the antibacterial activity against Staphylococcus aureus (ATCC 25923 and 33591 strains) and Klebsiella pneumoniae (ATCC 13883 and 700603 strains) was assessed by measuring the minimum inhibitory and the minimum bactericidal concentrations, in the exponential phase. Cells were observed by scanning electron microscopy, and the hemolytic activity of the peptides was assessed. The overall results demonstrate that, compared to linear analogues, polyvalent presentation of the RRWQWR motif enhances its antibacterial activity against both Gram-negative and Gram-positive bacteria even on resistant strain.
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10
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Crompton MJ, Dunstan RH. Evaluation of in-situ fatty acid extraction protocols for the analysis of staphylococcal cell membrane associated fatty acids by gas chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2018; 1084:80-88. [DOI: 10.1016/j.jchromb.2018.03.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/25/2018] [Accepted: 03/09/2018] [Indexed: 11/25/2022]
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11
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Itoh H, Tokumoto K, Kaji T, Paudel A, Panthee S, Hamamoto H, Sekimizu K, Inoue M. Total Synthesis and Biological Mode of Action of WAP-8294A2: A Menaquinone-Targeting Antibiotic. J Org Chem 2017; 83:6924-6935. [PMID: 29019678 DOI: 10.1021/acs.joc.7b02318] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
WAP-8294A2 (lotilibcin, 1) is a potent antibiotic with superior in vivo efficacy to vancomycin against methicillin-resistant Staphylococcus aureus (MRSA). Despite the great medical importance, its molecular mode of action remains unknown. Here we report the total synthesis of complex macrocyclic peptide 1 comprised of 12 amino acids with a β-hydroxy fatty-acid chain, and its deoxy analogue 2. A full solid-phase synthesis of 1 and 2 enabled their rapid assembly and the first detailed investigation of their functions. Compounds 1 and 2 were equipotent against various strains of Gram-positive bacteria including MRSA. We present evidence that the antimicrobial activities of 1 and 2 are due to lysis of the bacterial membrane, and their membrane-disrupting effects depend on the presence of menaquinone, an essential factor for the bacterial respiratory chain. The established synthetic routes and the menaquinone-targeting mechanisms provide valuable information for designing and developing new antibiotics based on their structures.
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Affiliation(s)
- Hiroaki Itoh
- Graduate School of Pharmaceutical Sciences , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-0033 , Japan
| | - Kotaro Tokumoto
- Graduate School of Pharmaceutical Sciences , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-0033 , Japan
| | - Takuya Kaji
- Graduate School of Pharmaceutical Sciences , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-0033 , Japan
| | - Atmika Paudel
- Teikyo University Institute of Medical Mycology , 359 Otsuka , Hachioji , Tokyo 192-0395 , Japan
| | - Suresh Panthee
- Teikyo University Institute of Medical Mycology , 359 Otsuka , Hachioji , Tokyo 192-0395 , Japan
| | - Hiroshi Hamamoto
- Teikyo University Institute of Medical Mycology , 359 Otsuka , Hachioji , Tokyo 192-0395 , Japan
| | - Kazuhisa Sekimizu
- Teikyo University Institute of Medical Mycology , 359 Otsuka , Hachioji , Tokyo 192-0395 , Japan
| | - Masayuki Inoue
- Graduate School of Pharmaceutical Sciences , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-0033 , Japan
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12
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Kaji T, Murai M, Itoh H, Yasukawa J, Hamamoto H, Sekimizu K, Inoue M. Total Synthesis and Functional Evaluation of Fourteen Derivatives of Lysocin E: Importance of Cationic, Hydrophobic, and Aromatic Moieties for Antibacterial Activity. Chemistry 2016; 22:16912-16919. [PMID: 27739191 DOI: 10.1002/chem.201604022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Indexed: 12/22/2022]
Abstract
Lysocin E (1) is a structurally complex 37-membered depsipeptide comprising 12 amino-acid residues with an N-methylated amide and an ester linkage. Compound 1 binds to menaquinone (MK) in the bacterial membrane to exert its potent bactericidal activity. To decipher the biologically important functionalities within this unique antibiotic, we performed a comprehensive structure-activity relationship (SAR) study by systematically changing the side-chain structures of l-Thr-1, d-Arg-2, N-Me-d-Phe-5, d-Arg-7, l-Glu-8, and d-Trp-10. First, we achieved total synthesis of the 14 new side-chain analogues of 1 by employing a solid-phase strategy. We then evaluated the MK-dependent liposomal disruption and antimicrobial activity against Staphylococcus aureus by 1 and its analogues. Correlating data between the liposome and bacteria experiments revealed that membrane lysis was mainly responsible for the antibacterial functions. Altering the cationic guanidine moiety of d-Arg-2/7 to a neutral amide, and the C7-acyl group of l-Thr-1 to the C2 or C11 counterpart decreased the antimicrobial activities four- or eight-fold. More drastically, chemical mutation of d-Trp-10 to d-Ala-10 totally abolished the bioactivities. These important findings led us to propose the biological roles of the side-chain functionalities.
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Affiliation(s)
- Takuya Kaji
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Motoki Murai
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Hiroaki Itoh
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Jyunichiro Yasukawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.,Faculty of Pharmaceutical Sciences, Doshisha Women's College of Liberal Arts, Kohdo, Kyotanabe, Kyoto, 610-0395, Japan
| | - Hiroshi Hamamoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.,Teikyo University Institute of Medical Mycology, 359 Otsuka, Hachioji, Tokyo, 192-0395, Japan
| | - Kazuhisa Sekimizu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.,Teikyo University Institute of Medical Mycology, 359 Otsuka, Hachioji, Tokyo, 192-0395, Japan
| | - Masayuki Inoue
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
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13
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The importance of cyclic structure for Labaditin on its antimicrobial activity against Staphylococcus aureus. Colloids Surf B Biointerfaces 2016; 148:453-459. [PMID: 27665378 DOI: 10.1016/j.colsurfb.2016.09.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 09/04/2016] [Accepted: 09/11/2016] [Indexed: 01/24/2023]
Abstract
Antimicrobial resistance has reached alarming levels in many countries, thus leading to a search for new classes of antibiotics, such as antimicrobial peptides whose activity is exerted by interacting specifically with the microorganism membrane. In this study, we investigate the molecular-level mechanism of action for Labaditin (Lo), a 10-amino acid residue cyclic peptide from Jatropha multifida with known bactericidal activity against Streptococcus mutans. We show that Lo is also effective against Staphylococcus aureus (S. aureus) but this does not apply to its linear analogue (L1). Using polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS), we observed with that the secondary structure of Lo was preserved upon interacting with Langmuir monolayers from a phospholipid mixture mimicking S. aureus membrane, in contrast to L1. This structure preservation for the rigid, cyclic Lo is key for the self-assembly of peptide nanotubes that induce pore formation in large unilamellar vesicles (LUVs), according to permeability assays and dynamic light scattering measurements. In summary, the comparison between Labaditin (Lo) and its linear analogue L1 allowed us to infer that the bactericidal activity of Lo is more related to its interaction with the membrane. It does not require specific metabolic targets, which makes cyclic peptides promising for antibiotics without bacteria resistance.
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14
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Hewelt-Belka W, Nakonieczna J, Belka M, Bączek T, Namieśnik J, Kot-Wasik A. Untargeted Lipidomics Reveals Differences in the Lipid Pattern among Clinical Isolates of Staphylococcus aureus Resistant and Sensitive to Antibiotics. J Proteome Res 2016; 15:914-22. [DOI: 10.1021/acs.jproteome.5b00915] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Weronika Hewelt-Belka
- Department
of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Joanna Nakonieczna
- Department
of Biotechnology, Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Kładki
24, 80-822 Gdańsk, Poland
| | - Mariusz Belka
- Department
of Pharmaceutical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, Al. Gen. J. Hallera 107, 80-416 Gdańsk, Poland
| | - Tomasz Bączek
- Department
of Pharmaceutical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, Al. Gen. J. Hallera 107, 80-416 Gdańsk, Poland
| | - Jacek Namieśnik
- Department
of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland
| | - Agata Kot-Wasik
- Department
of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk, Poland
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15
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Gonçalves FDA, de Carvalho CCCR. Phenotypic Modifications in Staphylococcus aureus Cells Exposed to High Concentrations of Vancomycin and Teicoplanin. Front Microbiol 2016; 7:13. [PMID: 26834731 PMCID: PMC4724715 DOI: 10.3389/fmicb.2016.00013] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 01/08/2016] [Indexed: 12/31/2022] Open
Abstract
Bacterial cells are known to change the fatty acid (FA) composition of the phospholipids as a phenotypic response to environmental conditions and to the presence of toxic compounds such as antibiotics. In the present study, Staphylococcus aureus cells collected during the exponential growth phase were challenged with 50 and 100 mg/L of vancomycin and teicoplanin, which are concentrations high enough to kill the large majority of the cell population. Colony-forming unit counts showed biphasic killing kinetics, typical for persister cell enrichment, in both antibiotics and concentrations tested. However, fluorescence microscopy showed the existence of viable but non-culturable (VBNC) cells in a larger number than that of possible persister cells. The analysis of the FA composition of the cells showed that, following antibiotic exposure up to 6 h, the survivor cells have an increased percentage of saturated FAs, a significant reduced percentage of branched FAs and an increased iso/anteiso branched FA ratio when compared to cells exhibiting a regular phenotype. This should result in lower membrane fluidity. However, cells exposed for 8-24 h presented an increased branched/saturated and lower iso/anteiso branched FA ratios, and thus increased membrane fluidity. Furthermore, the phenotypic changes were transmitted to daughter cells grown in drug-free media. The fact that VBNC cells presented nearly the same FA composition as those obtained after cell growth in drug-free media, which could only be the result of growth of persister cells, suggest that VBNC and persister phenotypes share the same type of response to antibiotics at the lipid level.
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Affiliation(s)
- Fábio D A Gonçalves
- iBB-Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa Lisbon, Portugal
| | - Carla C C R de Carvalho
- iBB-Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa Lisbon, Portugal
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16
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17
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Gustafson JE, Muthaiyan A, Dupre JM, Ricke SC. WITHDRAWN: Staphylococcus aureus and understanding the factors that impact enterotoxin production in foods: A review. Food Control 2014. [DOI: 10.1016/j.foodcont.2014.10.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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18
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Johnson GA, Ellis EA, Kim H, Muthukrishnan N, Snavely T, Pellois JP. Photoinduced membrane damage of E. coli and S. aureus by the photosensitizer-antimicrobial peptide conjugate eosin-(KLAKLAK)2. PLoS One 2014; 9:e91220. [PMID: 24608860 PMCID: PMC3946741 DOI: 10.1371/journal.pone.0091220] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 02/07/2014] [Indexed: 01/17/2023] Open
Abstract
Background/Objectives Upon irradiation with visible light, the photosensitizer-peptide conjugate eosin-(KLAKLAK)2 kills a broad spectrum of bacteria without damaging human cells. Eosin-(KLAKLAK)2 therefore represents an interesting lead compound for the treatment of local infection by photodynamic bacterial inactivation. The mechanisms of cellular killing by eosin-(KLAKLAK)2, however, remain unclear and this lack of knowledge hampers the development of optimized therapeutic agents. Herein, we investigate the localization of eosin-(KLAKLAK)2 in bacteria prior to light treatment and examine the molecular basis for the photodynamic activity of this conjugate. Methodology/Principal Findings By employing photooxidation of 3,3-diaminobenzidine (DAB), (scanning) transmission electron microscopy ((S)TEM), and energy dispersive X-ray spectroscopy (EDS) methodologies, eosin-(KLAKLAK)2 is visualized at the surface of E. coli and S. aureus prior to photodynamic irradiation. Subsequent irradiation leads to severe membrane damage. Consistent with these observations, eosin-(KLAKLAK)2 binds to liposomes of bacterial lipid composition and causes liposomal leakage upon irradiation. The eosin moiety of the conjugate mediates bacterial killing and lipid bilayer leakage by generating the reactive oxygen species singlet oxygen and superoxide. In contrast, the (KLAKLAK)2 moiety targets the photosensitizer to bacterial lipid bilayers. In addition, while (KLAKLAK)2 does not disrupt intact liposomes, the peptide accelerates the leakage of photo-oxidized liposomes. Conclusions/Significance Together, our results suggest that (KLAKLAK)2 promotes the binding of eosin Y to bacteria cell walls and lipid bilayers. Subsequent light irradiation results in membrane damage from the production of both Type I & II photodynamic products. Membrane damage by oxidation is then further aggravated by the (KLAKLAK)2 moiety and membrane lysis is accelerated by the peptide. These results therefore establish how photosensitizer and peptide act in synergy to achieve bacterial photo-inactivation. Learning how to exploit and optimize this synergy should lead to the development of future bacterial photoinactivation agents that are effective at low concentrations and at low light doses.
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Affiliation(s)
- Gregory A. Johnson
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - E. Ann Ellis
- Microscopy & Imaging Center, Texas A&M University, College Station, Texas, United States of America
| | - Hansoo Kim
- Microscopy & Imaging Center, Texas A&M University, College Station, Texas, United States of America
| | - Nandhini Muthukrishnan
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Thomas Snavely
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Jean-Philippe Pellois
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
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Duarte A, Slutsky M, Hanrahan G, Mello CM, Bazan GC. Supramolecular Electrostatic Nanoassemblies for Bacterial Forensics. Chemistry 2011; 18:756-9. [DOI: 10.1002/chem.201103237] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Indexed: 11/06/2022]
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20
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Characterization of Staphylococcus aureus cardiolipin synthases 1 and 2 and their contribution to accumulation of cardiolipin in stationary phase and within phagocytes. J Bacteriol 2011; 193:4134-42. [PMID: 21665977 DOI: 10.1128/jb.00288-11] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In many bacteria, including Staphylococcus aureus, progression from the logarithmic to the stationary phase is accompanied by conversion of most of bacterial membrane phosphatidylglycerol (PG) to cardiolipin (CL). Phagocytosis of S. aureus by human neutrophils also induces the conversion of most bacterial PG to CL. The genome of all sequenced strains of S. aureus contains two open reading frames (ORFs) predicting proteins encoded with ∼30% identity to the principal CL synthase (cls) of Escherichia coli. To test whether these ORFs (cls1 and cls2) encode cardiolipin synthases and contribute to CL accumulation in S. aureus, we expressed these proteins in a cls strain of E. coli and created isogenic single and double mutants in S. aureus. The expression of either Cls1 or Cls2 in CL-deficient E. coli resulted in CL accumulation in the stationary phase. S. aureus with deletion of both cls1 and cls2 showed no detectable CL accumulation in the stationary phase or after phagocytosis by neutrophils. CL accumulation in the stationary phase was due almost solely to Cls2, whereas both Cls1 and Cls2 contributed to CL accumulation following phagocytosis by neutrophils. Differences in the relative contributions of Cls1 and Cls2 to CL accumulation under different triggering conditions suggest differences in the role and regulation of these two enzymes.
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21
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Brinch-Iversen J, King GM. Effects of substrate concentration, growth state, and oxygen availability on relationships among bacterial carbon, nitrogen and phospholipid phosphorus content*. FEMS Microbiol Ecol 2011. [DOI: 10.1111/j.1574-6941.1990.tb01701.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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22
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Bieser AM, Tiller JC. Mechanistic considerations on contact-active antimicrobial surfaces with controlled functional group densities. Macromol Biosci 2011; 11:526-34. [PMID: 21229579 DOI: 10.1002/mabi.201000398] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 11/15/2010] [Indexed: 11/05/2022]
Abstract
A series of N-alkyl-N,N-dimethyldeoxyammonium celluloses is synthesized by converting tosyl celluloses with DBA and DDA, respectively. Surface coatings with these water-insoluble derivatives contain well-defined densities of quaternary ammonium functions and nonactive hydrophobic and hydrophilic groups. It is shown that the antimicrobial activity of such surfaces against S. aureus requires a delicate balance between DDA, BDA, and hydrophobic groups. A mechanism is proposed that involves the selective adhesion of anionic phospholipids from the bacterial cell membrane. This so-called phospholipid sponge effect is supported by the fact that all coatings could be deactivated by treatment with SDS or negatively charged phospholipids, but not with neutral phospholipids.
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Affiliation(s)
- Arno M Bieser
- Freiburg Material Research Center and Institute for Macromolecular Chemistry, Department of Chemistry, University of Freiburg, Stefan-Meier-Str. 21, D-79104 Freiburg, Germany
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23
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Cheng JTJ, Hale JD, Elliott M, Hancock REW, Straus SK. The importance of bacterial membrane composition in the structure and function of aurein 2.2 and selected variants. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1808:622-33. [PMID: 21144817 DOI: 10.1016/j.bbamem.2010.11.025] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Revised: 10/08/2010] [Accepted: 11/20/2010] [Indexed: 11/29/2022]
Abstract
For cationic antimicrobial peptides to become useful therapeutic agents, it is important to understand their mechanism of action. To obtain high resolution data, this involves studying the structure and membrane interaction of these peptides in tractable model bacterial membranes rather than directly utilizing more complex bacterial surfaces. A number of lipid mixtures have been used as bacterial mimetics, including a range of lipid headgroups, and different ratios of neutral to negatively charged headgroups. Here we examine how the structure and membrane interaction of aurein 2.2 and some of its variants depend on the choice of lipids, and how these models correlate with activity data in intact bacteria (MICs, membrane depolarization). Specifically, we investigated the structure and membrane interaction of aurein 2.2 and aurein 2.3 in 1:1 cardiolipin/1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (CL/POPG) (mol/mol), as an alternative to 1:1 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine(POPC)/POPG and a potential model for Gram positive bacteria such as S. aureus. The structure and membrane interaction of aurein 2.2, aurein 2.3, and five variants of aurein 2.2 were also investigated in 1:1 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE)/POPG (mol/mol) lipids as a possible model for other Gram positive bacteria, such as Bacillus cereus. Solution circular dichroism (CD) results demonstrated that the aurein peptides adopted α-helical structure in all lipid membranes examined, but demonstrated a greater helical content in the presence of POPE/POPG membranes. Oriented CD and ³¹P NMR results showed that the aurein peptides had similar membrane insertion profiles and headgroup disordering effects on POPC/POPG and CL/POPG bilayers, but demonstrated reduced membrane insertion and decreased headgroup disordering on mixing with POPE/POPG bilayers at low peptide concentrations. Since the aurein peptides behaved very differently in POPE/POPG membrane, minimal inhibitory concentrations (MICs) of the aurein peptides in B. cereus strain C737 were determined. The MIC results indicated that all aurein peptides are significantly less active against B. cereus than against S. aureus and S. epidermidis. Overall, the data suggest that it is important to use a relevant model for bacterial membranes to gain insight into the mode of action of a given antimicrobial peptide in specific bacteria.
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Affiliation(s)
- John T J Cheng
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T1Z1, Canada
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24
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Carotenoid-related alteration of cell membrane fluidity impacts Staphylococcus aureus susceptibility to host defense peptides. Antimicrob Agents Chemother 2010; 55:526-31. [PMID: 21115796 DOI: 10.1128/aac.00680-10] [Citation(s) in RCA: 156] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Carotenoid pigments of Staphylococcus aureus provide integrity to its cell membrane (CM) and limit oxidative host defense mechanisms. However, the role of carotenoids in staphylococcal resistance to nonoxidative host defenses has not been characterized. The current study examined the relationship among CM carotenoid content, membrane order, and in vitro susceptibility to daptomycin or to prototypic neutrophil-derived, platelet-derived, or bacterium-derived cationic antimicrobial peptides (human neutrophil defensin-1 [hNP-1], platelet microbicidal proteins [PMPs], or polymyxin B, respectively). A previously characterized methicillin-susceptible Staphylococcus aureus (MSSA) isogenic clinical strain set was used, including a parental isolate with an intact carotenoid biosynthetic operon (crtOPQMN) containing the crtM gene encoding early steps in staphyloxanthin biosynthesis, a crtM deletion mutant, and a crtMN multicopy plasmid-complemented variant. Compared to the parental and crtM knockout strains, the crtMN-complemented strain exhibited (i) increased carotenoid production, (ii) increased CM rigidity (P < 0.001), and (iii) uniformly reduced susceptibility to killing by the above-mentioned range of cationic peptides (statistically significant for hNP-1 [20 μg/ml]; P = 0.0037). There were no significant differences in phospholipid composition and asymmetry, fatty acid profiles, surface charge, or cell wall thickness among the strain set. Collectively, these data support the concept that carotenoid biosynthesis can contribute to the ability of S. aureus to subvert nonoxidative host defenses mediated by cationic peptides, potentially by increasing target membrane rigidity.
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25
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Singh AK, Zhang YM, Zhu K, Subramanian C, Li Z, Jayaswal RK, Gatto C, Rock CO, Wilkinson BJ. FabH selectivity for anteiso branched-chain fatty acid precursors in low-temperature adaptation in Listeria monocytogenes. FEMS Microbiol Lett 2009; 301:188-92. [PMID: 19863661 PMCID: PMC2818224 DOI: 10.1111/j.1574-6968.2009.01814.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Gram-positive bacteria, including Listeria monocytogenes, adjust membrane fluidity by shortening the fatty acid chain length and increasing the proportional production of anteiso fatty acids at lower growth temperatures. The first condensation reaction in fatty acid biosynthesis is carried out by beta-ketoacyl-acyl carrier protein synthase III (FabH), which determines the type of fatty acid produced in bacteria. Here, we measured the initial rates of FabH-catalyzed condensation of malonyl-acyl carrier protein and alternate branched-chain precursor acyl-CoAs utilizing affinity-purified His-tagged L. monocytogenes FabH heterologously expressed in Escherichia coli. Listeria monocytogenes FabH showed a preference for 2-methylbutyryl-CoA, the precursor of odd-numbered anteiso fatty acids, at 30 degrees C, which was further increased at a low temperature (10 degrees C), suggesting that temperature-dependent substrate selectivity of FabH underlies the increased formation of anteiso branched-chain fatty acids during low-temperature adaptation. The increased FabH preferential condensation of 2-methylbutyryl-CoA could not be attributed to a significantly higher availability of this fatty acid precursor as acyl-CoA pool levels were reduced similarly for all fatty acid precursors at low temperatures.
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Affiliation(s)
- Atul K Singh
- Microbiology Group, School of Biological Sciences, Illinois State University, Normal, IL 61790-4120, USA
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26
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Cheng JTJ, Hale JD, Elliot M, Hancock REW, Straus SK. Effect of membrane composition on antimicrobial peptides aurein 2.2 and 2.3 from Australian southern bell frogs. Biophys J 2009; 96:552-65. [PMID: 19167304 DOI: 10.1016/j.bpj.2008.10.012] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Accepted: 10/09/2008] [Indexed: 12/25/2022] Open
Abstract
The effects of hydrophobic thickness and the molar phosphatidylglycerol (PG) content of lipid bilayers on the structure and membrane interaction of three cationic antimicrobial peptides were examined: aurein 2.2, aurein 2.3 (almost identical to aurein 2.2, except for a point mutation at residue 13), and a carboxy C-terminal analog of aurein 2.3. Circular dichroism results indicated that all three peptides adopt an alpha-helical structure in the presence of a 3:1 molar mixture of 1,2-dimyristoyl-sn-glycero-3-phosphocholine/1,2-dimyristoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (DMPC/DMPG), and 1:1 and 3:1 molar mixtures of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine/1-palmitoyl-2-oleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (POPC/POPG). Oriented circular dichroism data for three different lipid compositions showed that all three peptides were surface-adsorbed at low peptide concentrations, but were inserted into the membrane at higher peptide concentrations. The (31)P solid-state NMR data of the three peptides in the DMPC/DMPG and POPC/POPG bilayers showed that all three peptides significantly perturbed lipid headgroups, in a peptide or lipid composition-dependent manner. Differential scanning calorimetry results demonstrated that both amidated aurein peptides perturbed the overall phase structure of DMPC/DMPG bilayers, but perturbed the POPC/POPG chains less. The nature of the perturbation of DMPC/DMPG bilayers was most likely micellization, and for the POPC/POPG bilayers, distorted toroidal pores or localized membrane aggregate formation. Calcein release assay results showed that aurein peptide-induced membrane leakage was more severe in DMPC/DMPG liposomes than in POPC/POPG liposomes, and that aurein 2.2 induced higher calcein release than aurein 2.3 and aurein 2.3-COOH from 1:1 and 3:1 POPC/POPG liposomes. Finally, DiSC(3)5 assay data further delineated aurein 2.2 from the others by showing that it perturbed the lipid membranes of intact S. aureus C622 most efficiently, whereas aurein 2.3 had the same efficiency as gramicidin S, and aurein 2.3-COOH was the least efficient. Taken together, these data show that the membrane interactions of aurein peptides are affected by the hydrophobic thickness of the lipid bilayers and the PG content.
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Affiliation(s)
- John T J Cheng
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
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27
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Insertional inactivation of branched-chain alpha-keto acid dehydrogenase in Staphylococcus aureus leads to decreased branched-chain membrane fatty acid content and increased susceptibility to certain stresses. Appl Environ Microbiol 2008; 74:5882-90. [PMID: 18689519 DOI: 10.1128/aem.00882-08] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus is a major community and nosocomial pathogen. Its ability to withstand multiple stress conditions and quickly develop resistance to antibiotics complicates the control of staphylococcal infections. Adaptation to lower temperatures is a key for the survival of bacterial species outside the host. Branched-chain alpha-keto acid dehydrogenase (BKD) is an enzyme complex that catalyzes the early stages of branched-chain fatty acid (BCFA) production. In this study, BKD was inactivated, resulting in reduced levels of BCFAs in the membrane of S. aureus. Growth of the BKD-inactivated mutant was progressively more impaired than that of wild-type S. aureus with decreasing temperature, to the point that the mutant could not grow at 12 degrees C. The growth of the mutant was markedly stimulated by the inclusion of 2-methylbutyrate in the growth medium at all temperatures tested. 2-Methylbutyrate is a precursor of odd-numbered anteiso fatty acids and bypasses BKD. Interestingly, growth of wild-type S. aureus was also stimulated by including 2-methylbutyrate in the medium, especially at lower temperatures. The anteiso fatty acid content of the BKD-inactivated mutant was restored by the inclusion of 2-methylbutyrate in the medium. Fluorescence polarization measurements indicated that the membrane of the BKD-inactivated mutant was significantly less fluid than that of wild-type S. aureus. Consistent with this result, the mutant showed decreased toluene tolerance that could be increased by the inclusion of 2-methylbutyrate in the medium. The BKD-inactivated mutant was more susceptible to alkaline pH and oxidative stress conditions. Inactivation of the BKD enzyme complex in S. aureus also led to a reduction in adherence of the mutant to eukaryotic cells and its survival in a mouse host. In addition, the mutant offers a tool to study the role of membrane fluidity in the interaction of S. aureus with antimicrobial substances.
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Structure and thermotropic behavior of the Staphylococcus aureus lipid lysyl-dipalmitoylphosphatidylglycerol. Biophys J 2007; 94:2150-9. [PMID: 18055539 DOI: 10.1529/biophysj.107.123422] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We have characterized the structural and thermotropic properties of one of the most important lipids in the cell membrane of Staphylococcus aureus, lysyl-dipalmitoylphosphatidylglycerol (lysyl-DPPG). applying differential scanning calorimetry and small- and wide-angle x-ray scattering. Microcalorimetry revealed that under physiological conditions (phosphate buffer, 20 mM NaPi, 130 mM NaCl, pH 7.4), the synthetic lysyl-DPPG resembles the features of the parent dipalmitoylphosphatidylglycerol (DPPG) with respect to its melting behavior. However, in contrast to DPPG, lowering the pH did not significantly affect the main transition temperature ( approximately 40 degrees C) of lysyl-DPPG, which can be explained by its difference in protonization because of the lysine group. X-ray experiments yielded the first information on chain packing and morphology of lysyl-DPPG. We found that lysyl-DPPG forms an interdigitated lamellar phase below the chain-melting transition. This can be explained by the large headgroup area of lysyl-DPPG as a result of its charged lysine group, especially if the headgroup is arranged parallel to the bilayer plane. Additionally, lysyl-DPPG degradation products, such as lysine and free fatty acids, had significant influences on the melting behavior and led to a multicomponent melting transition. Our results indicate that the degradation of lysyl-DPPG takes place mainly during the hydration process but also depends on lipid storage time, pH, and thermal treatment. Detailed temperature-resolved experiments at pH 5.0 demonstrated the formation of a lamellar gel phase with tilted hydrocarbon chains and a ripple phase, coexisting with the interdigitated lysyl-DPPG bilayers.
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Börjesson G, Sundh I, Svensson B. Microbial oxidation of CH4 at different temperatures in landfill cover soils. FEMS Microbiol Ecol 2004; 48:305-12. [DOI: 10.1016/j.femsec.2004.02.006] [Citation(s) in RCA: 166] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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30
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Abstract
The existing literature on the role of fatty acids in microbial temperature adaptation is reviewed. Several modes of change of cellular fatty acids at varying environmental temperatures are shown to exist in yeasts and fungi, Gram-negative bacteria, and bacteria containing iso- and anteiso-branched fatty acids, as well as in a few Gram-positive bacteria. Consequently, the degree of fatty acid unsaturation and cyclization, fatty acid chain length, branching, and cellular fatty acid content increase, decrease, or remain unaltered on lowering the temperature. Moreover, microorganisms seem to be able to change from one mode or alter the cellular fatty acid profile temperature dependently to another on lowering the temperature, as well as even within the same growth temperature range, depending on growth conditions. Therefore, the effect of the temperature on cellular fatty acids appears to be more complicated than known earlier. However, similarities found in the modes of change of cellular fatty acids at varying environmental temperatures in several microorganisms within the above mentioned groups support the existence of a limited amount of common regulatory mechanisms. The models presented enable the prediction of temperature-induced changes occurring in the fatty acids of microorganisms, and enzymatic steps of the fatty acid biosynthesis that possibly are under temperature control.
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Affiliation(s)
- M Suutari
- Helsinki University of Technology, Department of Chemical Engineering, Espoo, Finland
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31
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Asai S, Noda M, Yamamura M, Hozumi Y, Takase I, Nitta H, Sato M, Namikawa I. Comparative study of the cellular fatty acids of methicillin-resistant and -susceptible Staphylococcus aureus. APMIS 1993; 101:753-61. [PMID: 8267952 DOI: 10.1111/j.1699-0463.1993.tb00176.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The cellular fatty acid compositions of 26 strains of methicillin-resistant Staphylococcus aureus (MRSA) and 17 strains of methicillin-susceptible S. aureus (MSSA) were analyzed by gas-liquid chromatography. The fatty acid compositions of the two groups were very similar with 16 identified components. The major fatty acids were Ci14 = 0, Ci15 = 0, C18 = 0 and C20 = 0. Among these fatty acids, the percentage of the Ci15 = 0 fatty acid component of MRSA strains (11.4 +/- 3.9%) was statistically higher than that of MSSA strains (6.2 +/- 2.4%) (p < 0.001). On the other hand, the percentage of the C20 = 0 fatty acid components of MRSA strains (20.2 +/- 8.8%) was statistically lower than that of MSSA strains (30.7 +/- 10.4%) (p < 0.001). The production of beta-lactamase and beta-hemolysin in both groups' strain was also unrelated to the relative amounts of the fatty acid components. These results indicated a statistical tendency for the percentage fatty acid compositions of the MRSA strains to be quantitatively different from those of the MSSA for both the Ci15 = 0 and C20 = 0 fatty acid components. Analysis of the fatty acid compositions may have an application in the differentiation of MRSA and MSSA strains.
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Affiliation(s)
- S Asai
- Department of Oral Microbiology, School of Dentistry, Asahi University, Gifu Prefecture, Japan
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LI KENYUON, TORRES JANTONIO. EFFECTS of TEMPERATURE and SOLUTE ON the MINIMUM WATER ACTIVITY FOR GROWTH and TEMPERATURE CHARACTERISTIC of SELECTED MESOPHILES and PSYCHROTROPHS. J FOOD PROCESS PRES 1993. [DOI: 10.1111/j.1745-4549.1993.tb00733.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Nagamachi E, Hirai Y, Tomochika K, Kanemasa Y. Studies on osmotic stability of liposomes prepared with bacterial membrane lipids by carboxyfluorescein release. Microbiol Immunol 1992; 36:231-4. [PMID: 1602998 DOI: 10.1111/j.1348-0421.1992.tb01661.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The authors measured the osmotic stability of liposomes prepared with membrane lipids of bacteria, using the osmotic-shock release of entrapped carboxyfluorescein as an indicator. The sub-second physical changes of liposomes suspended in a solution of low osmotic pressure were examined by stopped flow spectrophotometry. The entrapped carboxyfluorescein was released when the liposomes burst on inflow of excess water. Liposomes prepared with the lipids of a stable Staphylococcus aureus L-form strain were more resistant to low osmotic pressure than those prepared from the wild strain of S. aureus, and liposomes prepared from Mycoplasma orale were even more resistant. Cardiolipin enhanced the lipid membrane stability in S. aureus and cholesterol in M. orale. The stability of lipid membranes to low osmotic pressure could be precisely determined by the present method.
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Affiliation(s)
- E Nagamachi
- Department of Health and Welfare, Junsei Junior College, Okayama, Japan
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Brinch-Iversen J, King G. Effects of substrate concentration, growth state, and oxygen availability on relationships among bacterial carbon, nitrogen and phospholipid phosphorus content*. FEMS Microbiol Lett 1990. [DOI: 10.1111/j.1574-6968.1990.tb04081.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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White DC. Environmental effects testing with quantitative microbial analysis: Chemical signatures correlated within situ biofilm analysis by FT/IR. ACTA ACUST UNITED AC 1986. [DOI: 10.1002/tox.2540010305] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Goldfine H. Lipids of Prokaryotes–Structure and Distribution. CURRENT TOPICS IN MEMBRANES AND TRANSPORT 1982. [DOI: 10.1016/s0070-2161(08)60307-x] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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38
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Hancock RL, Gerritsen N, Meadows H. Effects of chemical carcinogens on bacteria and yeast: a review. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1981; 7:607-42. [PMID: 6793732 DOI: 10.1080/15287398109530005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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39
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Bhakoo M, Herbert RA. Fatty acid and phospholipid composition of five psychrotrophic Pseudomonas spp. grown at different temperatures. Arch Microbiol 1980; 126:51-5. [PMID: 7396638 DOI: 10.1007/bf00421890] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The free fatty acid and phospholipid composition of 5 psychrotrophic marine Pseudomonas spp. have been determined in chemostat culture with glucose as the limiting substrate over the range 0--20 degrees C. The predominant fatty acid present in all the isolates was hexadecenoic acid (C 16:1) together with lesser quantities of octadecenoic acid (C 18:1) whilst none contained acids with chain lengths exceeding 18 carbon atoms. Decreasing the growth temperature from 20 degrees C to 0 degrees C resulted in little significant change in fatty acid composition. The principal phospholipid components of the five psychrotrophic pseudomonads have been identified as phosphatidylserine, phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol. Decreasing the growth temperature did not elicit significant changes either in the total quantities of phospholipid synthesized or in the concentration of individual phospholipid components in any of the isolates. All the psychrotrophs showed maximum glucose uptake between 15 degrees C and 20 degrees C and the rate decreased rapidly as the temperature was decreased towards 0 degrees C.
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40
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Veerkamp JH. Effects of growth conditions on the lipid composition of Bifidobacterium bifidum subsp. pennsylvanicum. Antonie Van Leeuwenhoek 1977; 43:101-10. [PMID: 596859 DOI: 10.1007/bf00395665] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Lipid-phosphorus and lipid-galactose content and phospholipid and fatty acid composition of Bifidobacterium bifidum subsp. pennsylvanicum were examined under a wide variety of growth conditions. Cells from 29-C cultures contained less lipid-phosphorus than did cells from 37-C cultures, but their lipid-galactose content and phospholipid composition did not differ. At both temperatures, the growth phase influenced the lipid composition similarly. Phosphate, Mg2+ and K+ concentrations in the medium did neither significantly change the cellular lipid-phosphorus content nor the phospholipid composition. Only Mg2+-deficiency markedly reduced growth and lowered the content of cellular lipid-galactose. Omission of Tween 80 from the medium did not affect growth, but lowered the content of lipid-galactose and augmented those of lipid-phosphorus and diphosphatidylglycerol in the cell. Increased osmolarity and substitution of other Tween for Tween 80 caused the same changes in lipid composition, and besides inhibited growth. Omitting Tween 80 and replacing it by other Tweens dramatically reduced the percentage of unsaturated fatty acids. C12- and C14-fatty acids made up about 50% of total fatty acids in cells from Tween 20 cultures and 12-14% in cells from Tween 40 and Tween 60 cultures. The differences in the decline of unsaturated fatty acids and in the degree of replacement of these acids by C12- and C14-fatty acids may be related to the variations in growth in cultures with various Tweens by way of changes in the physical state of the membrane lipids.
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Lechevalier MP. Lipids in bacterial taxonomy - a taxonomist's view. CRC CRITICAL REVIEWS IN MICROBIOLOGY 1977; 5:109-210. [PMID: 844323 DOI: 10.3109/10408417709102311] [Citation(s) in RCA: 295] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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42
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Dockter ME, Magnuson JA. Membrane phase transitions and the transport of chlortetracycline. Arch Biochem Biophys 1975; 168:81-8. [PMID: 1137402 DOI: 10.1016/0003-9861(75)90230-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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43
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Kusaka I. Degradation of phospholipid and release of diglyceride-rich membrane vesicles during protoplast formation in certain gram-positive bacteria. J Bacteriol 1975; 121:1173-9. [PMID: 803959 PMCID: PMC246050 DOI: 10.1128/jb.121.3.1173-1179.1975] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Membrane phospholipid was found to be hydrolyzed presumably by an intracellular phospholipase C, and diglyceride-rich membrane vesicles were released from the cells during protoplast formation in Bacillus cereus Bacillus subtilis, Micrococcus lysodeikticus, and Staphylococcus aureus. The released membranes consisted mainly of small vesicles of 50 to 100 nm in diameter. They have a lower density than that of protoplast membranes in all the bacteria tested in the present study.
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Durairaj G, Martin EW. The effect of temperature and diet on the fatty acid composition of Japanese quail. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1975; 50:237-48. [PMID: 1167351 DOI: 10.1016/0305-0491(75)90269-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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45
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Thirkell D, Gray EM. Variation in the lipid and fatty acid composition in purified membrane fractions from Sarcina aurantiaca in relation to growth phase. Antonie Van Leeuwenhoek 1974; 40:71-8. [PMID: 4545203 DOI: 10.1007/bf00394555] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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46
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Shaw N. Lipid composition as a guide to the classification of bacteria. ADVANCES IN APPLIED MICROBIOLOGY 1974; 17:63-108. [PMID: 4213752 DOI: 10.1016/s0065-2164(08)70555-0] [Citation(s) in RCA: 213] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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47
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Jetten AM, Vogels GD. Characteristics of the killing effect of a Staphylococcus epidermidis bacteriocin. Antonie Van Leeuwenhoek 1974; 40:177-83. [PMID: 4545195 DOI: 10.1007/bf00394565] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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48
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Alteration of the phospholipid composition of Staphylo-coccus aureus cultured in medium containing NaCl. ACTA ACUST UNITED AC 1972. [DOI: 10.1016/0005-2760(72)90251-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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49
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Kostiw LL, Boylen CW, Tyson BJ. Lipid composition of growing and starving cells of Arthrobacter crystallopoietes. J Bacteriol 1972; 111:103-11. [PMID: 4669211 PMCID: PMC251246 DOI: 10.1128/jb.111.1.103-111.1972] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The lipid composition of growing and starving cells of Arthrobacter crystallopoietes was compared. Although the lipid composition of the two cell types was similar, the amount of total lipids recovered from the starving cells was 30.4% less than that recovered from the growing cells. The loss of lipids, as compared to the loss of total cell mass during starvation, was (i) proportional to the loss of the cell mass (phosphatidylinositol, phosphatidylglycerol-2, and cardiolipin), (ii) greater than the loss in cell mass (neutral lipids, "glycophospholipids," and phosphatidic acid), or (iii) less than the loss in cell mass (coenzyme Q, glycolipids, and phosphatidylglycerol-1).
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50
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Hunter K, Rose AH. Lipid composition of Saccharomyces cerevisiae as influenced by growth temperature. BIOCHIMICA ET BIOPHYSICA ACTA 1972; 260:639-53. [PMID: 4554953 DOI: 10.1016/0005-2760(72)90013-6] [Citation(s) in RCA: 163] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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