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Perczyk P, Gawlak R, Broniatowski M. Interactions of fungal phospholipase Lecitase ultra with phospholipid Langmuir monolayers - Search for substrate specificity and structural factors affecting the activity of the enzyme. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183687. [PMID: 34175298 DOI: 10.1016/j.bbamem.2021.183687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 06/05/2021] [Accepted: 06/21/2021] [Indexed: 10/21/2022]
Abstract
Inoculation of selected microbial species into the soils is one of the most effective means of bioremediation of soils polluted by persistent organic pollutants as well as of biocontrol of plant pests. However, this procedure turns out frequently to be ineffective due to the membrane-destructive enzymes secreted to the soil by the autochthonous microorganisms. Especial role play here phospholipases and among them phospholipase A1 (PLA1), Therefore, to explain the interactions of microbial membranes and PLA1 at molecular level and to find the correlation between the composition of the membrane and its resistance to PLA1 action we applied phospholipid Langmuir monolayers as model microbial membranes. As a representative soil extracellular PLA1 we applied Lecitase ultra which is a commercially available hybrid enzyme of PLA1 activity. With the application of specific sn1-ether-sn2-ester phospholipids we proved that Lecitase ultra has solely PLA1 activity; thus, can be applied as an effective model of soil PLA1s. Our studies proved that this enzyme has vast substrate specificity and can hydrolyze structural phospholipids regardless the structure of their polar headgroup. It turned out that the hydrolysis rate was controlled by the condensation of the model membranes. These built of the phospholipids with long saturated fatty acid chains were especially resistant to the action of this enzyme, whereas these formed by the 1-saturated-2-unsaturated-sn-glycero-3-phospholipids were readily degraded. Regarding the polar headgroup we proposed the following row of substrate preference of Lecitase ultra: phosphatidylglycerols > phosphatidylcholines > phosphatidylethanolamines > cardiolipins.
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Affiliation(s)
- Paulina Perczyk
- Department of Environmental Chemistry, Faculty of Chemistry, the Jagiellonian University in Kraków, Gronostajowa 2, 30-387 Kraków, Poland
| | - Roksana Gawlak
- Department of Environmental Chemistry, Faculty of Chemistry, the Jagiellonian University in Kraków, Gronostajowa 2, 30-387 Kraków, Poland
| | - Marcin Broniatowski
- Department of Environmental Chemistry, Faculty of Chemistry, the Jagiellonian University in Kraków, Gronostajowa 2, 30-387 Kraków, Poland.
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Mahfouz S, Mansour G, Murphy DJ, Hanano A. Dioxin impacts on lipid metabolism of soil microbes: towards effective detection and bioassessment strategies. BIORESOUR BIOPROCESS 2020. [DOI: 10.1186/s40643-020-00347-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AbstractDioxins are the most toxic known environmental pollutants and are mainly formed by human activities. Due to their structural stability, dioxins persist for extended periods and can be transported over long distances from their emission sources. Thus, dioxins can be accumulated to considerable levels in both human and animal food chains. Along with sediments, soils are considered the most important reservoirs of dioxins. Soil microorganisms are therefore highly exposed to dioxins, leading to a range of biological responses that can impact the diversity, genetics and functional of such microbial communities. Dioxins are very hydrophobic with a high affinity to lipidic macromolecules in exposed organisms, including microbes. This review summarizes the genetic, molecular and biochemical impacts of dioxins on the lipid metabolism of soil microbial communities and especially examines modifications in the composition and architecture of cell membranes. This will provide a useful scientific benchmark for future attempts at soil ecological risk assessment, as well as in identifying potential dioxin-specific-responsive lipid biomarkers. Finally, potential uses of lipid-sequestering microorganisms as a part of biotechnological approaches to the bio-management of environmental contamination with dioxins are discussed.
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Perczyk P, Wójcik A, Hachlica N, Wydro P, Broniatowski M. The composition of phospholipid model bacterial membranes determines their endurance to secretory phospholipase A2 attack – The role of cardiolipin. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183239. [DOI: 10.1016/j.bbamem.2020.183239] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 10/24/2022]
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Manukumar H, Yashwanth B, Umesha S, Venkateswara Rao J. Biocidal mechanism of green synthesized thyme loaded silver nanoparticles (GTAgNPs) against immune evading tricky methicillin-resistant Staphylococcus aureus 090 (MRSA090) at a homeostatic environment. ARAB J CHEM 2020. [DOI: 10.1016/j.arabjc.2017.09.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Vijayan UK, Varakumar S, Singhal RS. A comparative account of extraction of oleoresin from Curcuma aromatica Salisb by solvent and supercritical carbon dioxide: Characterization and bioactivities. Lebensm Wiss Technol 2019. [DOI: 10.1016/j.lwt.2019.108564] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Ananda A, Manukumar H, Krishnamurthy N, Nagendra B, Savitha K. Assessment of antibacterial efficacy of a biocompatible nanoparticle PC@AgNPs against Staphylococcus aureus. Microb Pathog 2019; 126:27-39. [DOI: 10.1016/j.micpath.2018.10.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/21/2018] [Accepted: 10/22/2018] [Indexed: 11/28/2022]
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Ben Mouhoub R, El May A, Boujezza I, Sethom MM, Feki M, Landoulsi A. Viability and membrane lipid composition under a 57mT static magnetic field in Salmonella Hadar. Bioelectrochemistry 2018; 122:134-141. [PMID: 29627665 DOI: 10.1016/j.bioelechem.2018.03.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/27/2018] [Accepted: 03/28/2018] [Indexed: 10/17/2022]
Abstract
The aim of this work is to demonstrate the effects of a static magnetic field (SMF) with an induction 12 equal to 57mT on the viability and membrane lipid composition of Salmonella Hadar. Results showed an increase in the viability of exposed bacteria compared to controls after 9h of exposure. Analysis with gas chromatography of total lipids (TLs) and different fractions of phospholipids: phosphatidylglycerols (PGs), phosphatidylethanolamines (PEs), and cardiolipins (CLs), separated by thin layer chromatography revealed changes in fatty acid levels during exposure. For TLs, the unsaturated fatty acids/saturated fatty acids ratio (UFAs/SFAs) had significantly increased after 9 h of exposure. The variation of this ratio seems to be essentially due to the increase of the proportion of unsaturated fatty acids with 18 carbons, in particular C18:1. The analyses of fatty acid composition carried out on the scale of each fraction of phospholipids showed that CLs contributed significantly to the increase of the proportion of the unsaturated fatty acids between 6 and 9h of exposure thanks to their unsaturated chains with 18 carbons (especially C18:2). CLs appear to be the main phospholipid involved in the adaptation of S. Hadar membranes to the SMF.
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Affiliation(s)
- Ramla Ben Mouhoub
- Biochemistry and Molecular Biology, Code UR13ES34 Research Unit, Faculty of Sciences of Bizerte, Zarzouna 7021, Carthage University, Tunisia.
| | - Alya El May
- Biochemistry and Molecular Biology, Code UR13ES34 Research Unit, Faculty of Sciences of Bizerte, Zarzouna 7021, Carthage University, Tunisia
| | - Imen Boujezza
- Biochemistry and Molecular Biology, Code UR13ES34 Research Unit, Faculty of Sciences of Bizerte, Zarzouna 7021, Carthage University, Tunisia
| | - Mohamed Marouen Sethom
- Université de Tunis El Manar, Faculté de Médecine de Tunis, CHU La Rabta, Laboratoire de Biochimie, LR99ES11, Jebbari, 1007 Tunis, Tunisia
| | - Moncef Feki
- Université de Tunis El Manar, Faculté de Médecine de Tunis, CHU La Rabta, Laboratoire de Biochimie, LR99ES11, Jebbari, 1007 Tunis, Tunisia
| | - Ahmed Landoulsi
- Biochemistry and Molecular Biology, Code UR13ES34 Research Unit, Faculty of Sciences of Bizerte, Zarzouna 7021, Carthage University, Tunisia
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Králová S. Role of fatty acids in cold adaptation of Antarctic psychrophilic Flavobacterium spp. Syst Appl Microbiol 2017; 40:329-333. [DOI: 10.1016/j.syapm.2017.06.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 06/08/2017] [Accepted: 06/12/2017] [Indexed: 10/19/2022]
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Kalily E, Hollander A, Korin B, Cymerman I, Yaron S. Adaptation of Salmonella enterica Serovar Senftenberg to Linalool and Its Association with Antibiotic Resistance and Environmental Persistence. Appl Environ Microbiol 2017; 83:e03398-16. [PMID: 28258149 PMCID: PMC5411494 DOI: 10.1128/aem.03398-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 02/22/2017] [Indexed: 11/20/2022] Open
Abstract
A clinical isolate of Salmonella enterica serovar Senftenberg, isolated from an outbreak linked to the herb Ocimum basilicum L. (basil), has been shown to be resistant to basil oil and to the terpene alcohol linalool. To better understand how human pathogens might develop resistance to linalool and to investigate the association of this resistance with resistance to different antimicrobial agents, selective pressure was applied to the wild-type strain by sequential exposure to increasing concentrations of linalool. The results demonstrated that S Senftenberg adapted to linalool with a MIC increment of at least 8-fold, which also resulted in better resistance to basil oil and better survival on harvested basil leaves. Adaptation to linalool was shown to confer cross protection against the antibiotics trimethoprim, sulfamethoxazole, piperacillin, chloramphenicol, and tetracycline, increasing their MICs by 2- to 32-fold. The improved resistance was shown to correlate with multiple phenotypes that included changes in membrane fatty acid composition, induced efflux, reduced influx, controlled motility, and the ability to form larger aggregates in the presence of linalool. The adaptation to linalool obtained in vitro did not affect survival on the basil phyllosphere in planta and even diminished survival in soil, suggesting that development of extreme resistance to linalool may be accompanied by a loss of fitness. Altogether, this report notes the concern regarding the ability of human pathogens to develop resistance to commercial essential oils, a resistance that is also associated with cross-resistance to antibiotics and may endanger public health.IMPORTANCE Greater consumer awareness and concern regarding synthetic chemical additives have led producers to control microbial spoilage and hazards by the use of natural preservatives, such as plant essential oils with antimicrobial activity. This report establishes, however, that these compounds may provoke the emergence of resistant human pathogens. Herein, we demonstrate the acquisition of resistance to basil oil by Salmonella Senftenberg. Exposure to linalool, a component of basil oil, resulted in adaptation to the basil oil mixture, as well as cross protection against several antibiotics and better survival on harvested basil leaves. Collectively, this work highlights the hazard to public health while using plant essential oils without sufficient knowledge about their influence on pathogens at subinhibitory concentrations.
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Affiliation(s)
- Emmanuel Kalily
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
| | - Amit Hollander
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
| | - Ben Korin
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
| | - Itamar Cymerman
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
| | - Sima Yaron
- Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel
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Influence of static magnetic field exposure on fatty acid composition in Salmonella Hadar. Microb Pathog 2017; 108:13-20. [PMID: 28455137 DOI: 10.1016/j.micpath.2017.04.035] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 04/23/2017] [Accepted: 04/24/2017] [Indexed: 11/20/2022]
Abstract
We have been interested, in this work, to investigate the effect of the exposure to static magnetic field at 200 mT (SMF) on the fatty acid (FA) composition of Salmonella enterica subsp Enterica serovar Hadar isolate 287: effects on the proportion of saturated and unsaturated fatty acids (SFAs, UFAs), cyclopropane fatty acids (CFAs) and hydroxy fatty acids after exposure to the static magnetic field at 200 mT (SMF). Analysis with Gas Chromatography-Mass Spectrometry (GC-MS) of total lipid showed that the proportion of the most fatty acids was clearly affected. The comparison of UFAs/SFAs ratio in exposed bacteria and controls showed a diminution after 3 and 6 h of exposure. This ration reached a balance after 9 h of treatment with SMF. So we can conclude that S. Hadar tries to adapt to magnetic stress by changing the proportions of SFAs and UFAs over time to maintain an equilibrium after 9 h of exposure, thus to maintain the inner membranes fluidity. Also, a decrease in the proportion of hydroxy FAs was observed after 6 h but an increase of this proportion after 9 h of exposure. Concerning CFAs, its proportion raised after 6 h of exposure to the SMF but it decreased after 9 h of exposure. These results are strongly correlated with those of cfa (cyclopropane fatty acid synthase) gene expression which showed a decrease of its expression after 9 h of exposure.
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Lyu F, Gao F, Wei Q, Liu L. Changes of membrane fatty acids and proteins of Shewanella putrefaciens treated with cinnamon oil and gamma irradiation. BIORESOUR BIOPROCESS 2017; 4:10. [PMID: 28203517 PMCID: PMC5283506 DOI: 10.1186/s40643-017-0140-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/19/2017] [Accepted: 01/23/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In order to detect the antimicrobial mechanism of combined treatment of cinnamon oil and gamma irradiation (GI), the membrane fatty acids and proteins characteristics of Shewanella putrefaciens (S. putrefaciens) treated with cinnamon oil and GI, and the distribution of cinnamon oil in S. putrefaciens were observed in this study. RESULTS The membrane lipid profile of S. putrefaciens was notably damaged by treatments of cinnamon oil and the combination of cinnamon oil and GI, with significantly fatty acids decrease in C14:0, C16:0, C16:1, C17:1, C18:1 (p < 0.05). The SDS-PAGE result showed that GI did not have obvious effect on membrane proteins (MP), but GI combined with cinnamon oil changed the MP subunits. Cinnamaldehyde, the main component of cinnamon oil, can not transport into S. putrefaciens obviously. It was transformed into cinnamyl alcohol in the nutrient broth with the action of S. putrefaciens. This indicated that the antimicrobial action of cinnamon oil mainly happened on the membrane of S. putrefaciens. CONCLUSION Cinnamon oil could act on the membrane of S. putrefaciens with the damage of fatty acids and proteins, and GI would increase the destructive capability of cinnamon oil on the membrane fatty acids and proteins of S. putrefaciens.
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Affiliation(s)
- Fei Lyu
- Department of Food Science, Ocean College, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, 310014 China
| | - Fei Gao
- Department of Food Science, Ocean College, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, 310014 China
| | - Qianqian Wei
- Department of Food Science, Ocean College, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, 310014 China
| | - Lin Liu
- Department of Food Science, Ocean College, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, 310014 China
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Affiliation(s)
- John A Wright
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, UK
| | - Clare E Bryant
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, UK
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Leite de Souza E. The effects of sublethal doses of essential oils and their constituents on antimicrobial susceptibility and antibiotic resistance among food-related bacteria: A review. Trends Food Sci Technol 2016. [DOI: 10.1016/j.tifs.2016.07.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Sohlenkamp C, Geiger O. Bacterial membrane lipids: diversity in structures and pathways. FEMS Microbiol Rev 2015; 40:133-59. [DOI: 10.1093/femsre/fuv008] [Citation(s) in RCA: 571] [Impact Index Per Article: 63.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2015] [Indexed: 12/22/2022] Open
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Abstract
Since the first application of high hydrostatic pressure (HHP) for food preservation more than 100 years ago, a wealth of knowledge has been gained on molecular mechanisms underlying the HHP-mediated destruction of microorganisms. However, one observation made back then is still valid, i.e. that HHP alone is not sufficient for the complete inactivation of bacterial endospores. To achieve "commercial sterility" of low-acid foods, i.e. inactivation of spores capable of growing in a specific product under typical storage conditions, a combination of HHP with other hurdles is required (most effectively with heat (HPT)). Although HPT processes are not yet industrially applied, continuous technical progress and increasing consumer demand for minimally processed, additive-free food with long shelf life, makes HPT sterilization a promising alternative to thermal processing.In recent years, considerable progress has been made in understanding the response of spores of the model organism B. subtilis to HPT treatments and detailed insights into some basic mechanisms in Clostridium species shed new light on differences in the HPT-mediated inactivation of Bacillus and Clostridium spores. In this chapter, current knowledge on sporulation and germination processes, which presents the basis for understanding development and loss of the extreme resistance properties of spores, is summarized highlighting commonalities and differences between Bacillus and Clostridium species. In this context, the effect of HPT treatments on spores, inactivation mechanism and kinetics, the role of population heterogeneity, and influence factors on the results of inactivation studies are discussed.
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Affiliation(s)
- Christian A Lenz
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München, 85354, Freising, Germany
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Larocque M, Chénard T, Najmanovich R. A curated C. difficile strain 630 metabolic network: prediction of essential targets and inhibitors. BMC SYSTEMS BIOLOGY 2014; 8:117. [PMID: 25315994 PMCID: PMC4207893 DOI: 10.1186/s12918-014-0117-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 10/08/2014] [Indexed: 12/12/2022]
Abstract
BACKGROUND Clostridium difficile is the leading cause of hospital-borne infections occurring when the natural intestinal flora is depleted following antibiotic treatment. Current treatments for Clostridium difficile infections present high relapse rates and new hyper-virulent and multi-resistant strains are emerging, making the study of this nosocomial pathogen necessary to find novel therapeutic targets. RESULTS We present iMLTC806cdf, an extensively curated reconstructed metabolic network for the C. difficile pathogenic strain 630. iMLTC806cdf contains 806 genes, 703 metabolites and 769 metabolic, 117 exchange and 145 transport reactions. iMLTC806cdf is the most complete and accurate metabolic reconstruction of a gram-positive anaerobic bacteria to date. We validate the model with simulated growth assays in different media and carbon sources and use it to predict essential genes. We obtain 89.2% accuracy in the prediction of gene essentiality when compared to experimental data for B. subtilis homologs (the closest organism for which such data exists). We predict the existence of 76 essential genes and 39 essential gene pairs, a number of which are unique to C. difficile and have non-existing or predicted non-essential human homologs. For 29 of these potential therapeutic targets, we find 125 inhibitors of homologous proteins including approved drugs with the potential for drug repositioning, that when validated experimentally could serve as starting points in the development of new antibiotics. CONCLUSIONS We created a highly curated metabolic network model of C. difficile strain 630 and used it to predict essential genes as potential new therapeutic targets in the fight against Clostridium difficile infections.
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Affiliation(s)
- Mathieu Larocque
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H 5N4, Canada.
| | - Thierry Chénard
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H 5N4, Canada.
| | - Rafael Najmanovich
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H 5N4, Canada.
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Dahlsten E, Lindström M, Korkeala H. Mechanisms of food processing and storage-related stress tolerance in Clostridium botulinum. Res Microbiol 2014; 166:344-52. [PMID: 25303833 DOI: 10.1016/j.resmic.2014.09.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 09/26/2014] [Accepted: 09/26/2014] [Indexed: 12/28/2022]
Abstract
Vegetative cultures of Clostridium botulinum produce the extremely potent botulinum neurotoxin, and may jeopardize the safety of foods unless sufficient measures to prevent growth are applied. Minimal food processing relies on combinations of mild treatments, primarily to avoid deterioration of the sensory qualities of the food. Tolerance of C. botulinum to minimal food processing is well characterized. However, data on effects of successive treatments on robustness towards further processing is lacking. Developments in genetic manipulation tools and the availability of annotated genomes have allowed identification of genetic mechanisms involved in stress tolerance of C. botulinum. Most studies focused on low temperature, and the importance of various regulatory mechanisms in cold tolerance of C. botulinum has been demonstrated. Furthermore, novel roles in cold tolerance were shown for metabolic pathways under the control of these regulators. A role for secondary oxidative stress in tolerance to extreme temperatures has been proposed. Additionally, genetic mechanisms related to tolerance to heat, low pH, and high salinity have been characterized. Data on genetic stress-related mechanisms of psychrotrophic Group II C. botulinum strains are scarce; these mechanisms are of interest for food safety research and should thus be investigated. This minireview encompasses the importance of C. botulinum as a food safety hazard and its central physiological characteristics related to food-processing and storage-related stress. Special attention is given to recent findings considering genetic mechanisms C. botulinum utilizes in detecting and countering these adverse conditions.
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Affiliation(s)
- Elias Dahlsten
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P. O. Box 66, FI-00014 Helsinki, Finland.
| | - Miia Lindström
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P. O. Box 66, FI-00014 Helsinki, Finland.
| | - Hannu Korkeala
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P. O. Box 66, FI-00014 Helsinki, Finland.
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The cold-induced two-component system CBO0366/CBO0365 regulates metabolic pathways with novel roles in group I Clostridium botulinum ATCC 3502 cold tolerance. Appl Environ Microbiol 2013; 80:306-19. [PMID: 24162575 DOI: 10.1128/aem.03173-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The two-component system CBO0366/CBO0365 was recently demonstrated to have a role in cold tolerance of group I Clostridium botulinum ATCC 3502. The mechanisms under its control, ultimately resulting in increased sensitivity to low temperature, are unknown. A transcriptomic analysis with DNA microarrays was performed to identify the differences in global gene expression patterns of the wild-type ATCC 3502 and a derivative mutant with insertionally inactivated cbo0365 at 37 and 15°C. Altogether, 150 or 141 chromosomal coding sequences (CDSs) were found to be differently expressed in the cbo0365 mutant at 37 or 15°C, respectively, and thus considered to be under the direct or indirect transcriptional control of the response regulator CBO0365. Of the differentially expressed CDSs, expression of 141 CDSs was similarly affected at both temperatures investigated, suggesting that the putative CBO0365 regulon was practically not affected by temperature. The regulon involved genes related to acetone-butanol-ethanol (ABE) fermentation, motility, arsenic resistance, and phosphate uptake and transport. Deteriorated growth at 17°C was observed for mutants with disrupted ABE fermentation pathway components (crt, bcd, bdh, and ctfA), arsenic detoxifying machinery components (arsC and arsR), or phosphate uptake mechanism components (phoT), suggesting roles for these mechanisms in cold tolerance of group I C. botulinum. Electrophoretic mobility shift assays showed recombinant CBO0365 to bind to the promoter regions of crt, arsR, and phoT, as well as to the promoter region of its own operon, suggesting direct DNA-binding transcriptional activation or repression as a means for CBO0365 in regulating these operons. The results provide insight to the mechanisms group I C. botulinum utilizes in coping with cold.
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Derman Y, Isokallio M, Lindström M, Korkeala H. The two-component system CBO2306/CBO2307 is important for cold adaptation of Clostridium botulinum ATCC 3502. Int J Food Microbiol 2013; 167:87-91. [PMID: 23810493 DOI: 10.1016/j.ijfoodmicro.2013.06.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 05/31/2013] [Accepted: 06/06/2013] [Indexed: 10/26/2022]
Abstract
Clostridium botulinum is a notorious foodborne pathogen. Its ability to adapt to and grow at low temperatures is of interest for food safety. Two-component systems (TCSs) have been reported to be involved in cold-shock and growth at low temperatures. Here we show the importance of TCS CBO2306/CBO2307 in the cold-shock response of C. botulinum ATCC 3502. The relative expression levels of the cbo2306 and cbo2307 were up to 4.4-fold induced in the cold-shocked cultures but negatively regulated in the late-log and stationary growth phase in relation to early logarithmic growth phase in non-shocked cultures. Importance of the CBO2306/CBO2307 in the cold stress was further demonstrated by impaired growth of insertional cbo2306 or cbo2307 knockout mutants in relation to the wild-type strain ATCC 3502. The results suggest that the TCS CBO2306/CBO2307 is important for cold-shock response and adaptation of C. botulinum ATCC 3502 to low temperature.
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Affiliation(s)
- Yağmur Derman
- Department of Food Hygiene and Environmental Health, The Centre of Excellence in Microbial Food Safety Research, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
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Guan Z, Johnston NC, Raetz CRH, Johnson EA, Goldfine H. Lipid diversity among botulinum neurotoxin-producing clostridia. MICROBIOLOGY-SGM 2012; 158:2577-2584. [PMID: 22837302 DOI: 10.1099/mic.0.060707-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Clostridium botulinum has been classified into four groupings (groups I to IV) based on physiological characteristics and 16S rRNA sequencing. We have examined the lipid compositions of 11 representative strains of C. botulinum and a strain of Clostridium sporogenes by 2D-TLC and by MS. All strains contained phosphatidylglycerol (PG), cardiolipin (CL) and phosphatidylethanolamine (PE) in both the all-acyl and the alk-1'-enyl (plasmalogen) forms. Five strains in proteolytic group I, which are related to C. sporogenes, contained varying amounts of an ethanolamine-phosphate derivative of N-acetylglucosaminyl-diradylglycerol, which is also present in C. sporogenes. Three strains in group II, which are related to Clostridium butyricum, Clostridium beijerinckii and Clostridium acetobutylicum, contained lipids characteristic of these saccharolytic species: a glycerol acetal and a PG acetal of the plasmalogen form of PE. Two group III strains, which are related to Clostridium novyi, contained amino-acyl derivatives of PG, which are also found in C. novyi. A strain in group IV had PE, PG and CL, but none of the distinguishing lipids. This work shows that the lipidome of C. botulinum is consistent with its classification by other methods.
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Affiliation(s)
- Ziqiang Guan
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Norah C Johnston
- Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Christian R H Raetz
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Eric A Johnson
- Department of Bacteriology, Botulinum Toxins Laboratory, Food Research Institute, University of Wisconsin, Madison, WI 53706, USA
| | - Howard Goldfine
- Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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Involvement of two-component system CBO0366/CBO0365 in the cold shock response and growth of group I (proteolytic) Clostridium botulinum ATCC 3502 at low temperatures. Appl Environ Microbiol 2012; 78:5466-70. [PMID: 22660717 DOI: 10.1128/aem.00555-12] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The role of the two-component system (TCS) CBO0366/CBO0365 in the cold shock response and growth of the mesophilic Clostridium botulinum ATCC 3502 at 15°C was demonstrated by induced expression of the TCS genes upon cold shock and impaired growth of the TCS mutants at 15°C.
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22
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Mihoub M, El May A, Aloui A, Chatti A, Landoulsi A. Effects of static magnetic fields on growth and membrane lipid composition of Salmonella typhimurium wild-type and dam mutant strains. Int J Food Microbiol 2012; 157:259-66. [PMID: 22682582 DOI: 10.1016/j.ijfoodmicro.2012.05.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 04/22/2012] [Accepted: 05/18/2012] [Indexed: 01/12/2023]
Abstract
This study was carried out to explore the adaptive mechanisms of S. typhimurium particularly, the implication of the Dam methyltransferase in the remodelling of membrane lipid composition to overcome magnetic field stress. With this aim, we focused our analyses on the increase in viable numbers and membrane lipid modifications of S. typhimurium wild-type and dam mutant cells exposed for 10h to static magnetic fields (SMF; 200 mT). For the wild-type strain, exposure to SMF induced a significant decrease (p<0.05) of CFU at 6h, followed by an increase between 8 and 10h. Growth of the dam mutant was significantly affected (p<0.05) after 6h and no recovery was observed until 10h, highlighting a different behavior of SMF stressed wild-type and dam mutant strains. SMF significantly affected the phospholipid proportions in the two strains. The most affected were those of the acidic phospholipids, cardiolipins (CL). In the dam strain the phospholipid response to SMF followed a globally similar trend as in the wild-type with however lower effects, leading mainly to an unusual accumulation of CL. This would in part explain the different behavior of the wild-type and the dam strain. Results showed a significant increase of membrane cyclic fatty acids Cyc17 and Cyc19 in the wild-type strain but only the Cyc17 in the dam strain and a meaningful increase of the total unsaturated fatty acids (UFAs) to total saturated fatty acids (SFAs) ratios of the exposed cells compared to controls from 3 to 9h (p<0.05) for both strains. The net increase of the total UFAs to total SFAs ratios seemed to result mainly from the increase of (C18:1) proportion (p<0.05) and to a lower extent from that of (C16:1) (p<0.05). These modifications of cyclic and unsaturated fatty acid proportions constitute an adaptive response to SMF stress in S. typhimurium wild-type and dam mutants to maintain an optimum level of membrane fluidity under SMF.
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Affiliation(s)
- Mouadh Mihoub
- Unité de Biochimie des Lipides et Interaction des Macromolécules en Biologie (03/UR/0902), Laboratoire de Biochimie et Biologie Moléculaire, Faculté des Sciences de Bizerte, Zarzouna, Bizerte, Tunisia.
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23
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Ayari S, Dussault D, Millette M, Hamdi M, Lacroix M. Response of Bacillus cereus to gamma-irradiation in combination with carvacrol or mild heat treatment. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:8217-8224. [PMID: 20568774 DOI: 10.1021/jf101044f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Carvacrol and mild heat treatment were tested for their efficiency to increase the radiosensitivity of Bacillus cereus in broth. The bacterium was treated with gamma-irradiation alone or in combination with carvacrol at its minimal inhibitory concentration or mild heat treatment for 10 min at 45 degrees C. The effects of this combination of treatments were studied on various parameters: the bacterial viability, the modifications of the cell morphology with scanning electron microscopy (SEM), the cellular fatty acids composition of the membrane quantified by gas chromatography, the intracellular and extracellular adenosine 5'-triphosphate (ATP) concentrations, and the DNA degradation. Combined treatments resulted in additive or synergistic effects as compared to gamma-irradiation alone. A significant modification (P < or = 0.05) of the fatty acid composition and unsaturation ratios was observed. Pretreatment with mild heat or carvacrol before irradiation disturbed the membrane integrity of B. cereus and induced a significant decrease (P < or = 0.05) of the intracellular ATP concentration. SEM observations revealed that the cell membrane was more severely affected with combined treatment than irradiation alone. The electrophoresis analysis showed that DNA degradation by combined treatments was greater than the gamma-irradiation alone.
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Affiliation(s)
- Samia Ayari
- National Center for Nuclear Sciences and Technologies, Tunis Cedex, Tunisia
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24
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Szymanski J, Jozefczuk S, Nikoloski Z, Selbig J, Nikiforova V, Catchpole G, Willmitzer L. Stability of metabolic correlations under changing environmental conditions in Escherichia coli--a systems approach. PLoS One 2009; 4:e7441. [PMID: 19829699 PMCID: PMC2759078 DOI: 10.1371/journal.pone.0007441] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Accepted: 09/15/2009] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Biological systems adapt to changing environments by reorganizing their cellular and physiological program with metabolites representing one important response level. Different stresses lead to both conserved and specific responses on the metabolite level which should be reflected in the underlying metabolic network. METHODOLOGY/PRINCIPAL FINDINGS Starting from experimental data obtained by a GC-MS based high-throughput metabolic profiling technology we here develop an approach that: (1) extracts network representations from metabolic condition-dependent data by using pairwise correlations, (2) determines the sets of stable and condition-dependent correlations based on a combination of statistical significance and homogeneity tests, and (3) can identify metabolites related to the stress response, which goes beyond simple observations about the changes of metabolic concentrations. The approach was tested with Escherichia coli as a model organism observed under four different environmental stress conditions (cold stress, heat stress, oxidative stress, lactose diauxie) and control unperturbed conditions. By constructing the stable network component, which displays a scale free topology and small-world characteristics, we demonstrated that: (1) metabolite hubs in this reconstructed correlation networks are significantly enriched for those contained in biochemical networks such as EcoCyc, (2) particular components of the stable network are enriched for functionally related biochemical pathways, and (3) independently of the response scale, based on their importance in the reorganization of the correlation network a set of metabolites can be identified which represent hypothetical candidates for adjusting to a stress-specific response. CONCLUSIONS/SIGNIFICANCE Network-based tools allowed the identification of stress-dependent and general metabolic correlation networks. This correlation-network-based approach does not rely on major changes in concentration to identify metabolites important for stress adaptation, but rather on the changes in network properties with respect to metabolites. This should represent a useful complementary technique in addition to more classical approaches.
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Affiliation(s)
- Jedrzej Szymanski
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Szymon Jozefczuk
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Zoran Nikoloski
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Joachim Selbig
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Victoria Nikiforova
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
- Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow, Russia
| | - Gareth Catchpole
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Lothar Willmitzer
- Max-Planck Institute for Molecular Plant Physiology, Potsdam, Germany
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Dussault D, Caillet S, Le Tien C, Lacroix M. Effect of γ-irradiation on membrane fatty acids and peptidoglycan’s muropeptides ofPantoea agglomerans, a plant pathogen. J Appl Microbiol 2009; 106:1033-40. [DOI: 10.1111/j.1365-2672.2008.04070.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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26
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Analysis of composition and structure of Clostridium thermocellum membranes from wild-type and ethanol-adapted strains. Appl Microbiol Biotechnol 2009; 82:929-39. [PMID: 19221734 DOI: 10.1007/s00253-009-1891-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Revised: 01/14/2009] [Accepted: 01/20/2009] [Indexed: 10/21/2022]
Abstract
Clostridium thermocellum is a candidate organism for consolidated bioprocessing of lignocellulosic biomass into ethanol. However, commercial use is limited due to growth inhibition at modest ethanol concentrations. Recently, an ethanol-adapted strain of C. thermocellum was produced. Since ethanol adaptation in microorganisms has been linked to modification of membrane lipids, we tested the hypothesis that ethanol adaptation in C. thermocellum involves lipid modification by comparing the fatty acid composition and membrane anisotropy of wild-type and ethanol-adapted strains. Derivatization to fatty acid methyl esters provided quantitative lipid analysis. Compared to wild-type, the ethanol-adapted strain had a larger percentage of fatty acids with chain lengths >16:0 and showed a significant increase in the percentage of 16:0 plasmalogens. Structural identification of fatty acids was confirmed through mass spectral fragmentation patterns of picolinyl esters. Ethanol adaptation did not involve modification at sites of methyl branching or the unsaturation index. Comparison of steady-state fluorescence anisotropy experiments, in the absence and presence of ethanol, provided evidence for the effects of ethanol on membrane fluidity. In the presence of ethanol, both strains displayed increased fluidity by approximately 12%. These data support the model that ethanol adaptation was the result of fatty acid changes that increased membrane rigidity that counter-acted the fluidizing effect of ethanol.
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Di Pasqua R, Betts G, Hoskins N, Edwards M, Ercolini D, Mauriello G. Membrane toxicity of antimicrobial compounds from essential oils. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:4863-70. [PMID: 17497876 DOI: 10.1021/jf0636465] [Citation(s) in RCA: 362] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Natural antimicrobial compounds perform their action mainly against cell membranes. The aim of this work was to evaluate the interaction, meant as a mechanism of action, of essential oil antimicrobial compounds with the microbial cell envelope. The lipid profiles of Escherichia coli O157:H7, Staphylococcus aureus, Salmonella enterica serovar Typhimurium, Pseudomonas fluorescens, and Brochothrix thermosphacta cells treated with thymol, carvacrol, limonene, eugenol, and cinnamaldehyde have been analyzed by gas chromatography. In line with the fatty acids analysis, the treated cells were also observed by scanning electron microscopy (SEM) to evaluate structural alterations. The overall results showed a strong decrease of the unsaturated fatty acids (UFAs) for the treated cells; in particular, the C18:2trans and C18:3cis underwent a notable reduction contributing to the total UFA decreases, while the saturated fatty acid C17:0 raised the highest concentration in cinnamaldehyde-treated cells. SEM images showed that the used antimicrobial compounds quickly exerted their antimicrobial activities, determining structural alterations of the cell envelope.
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Affiliation(s)
- Rosangela Di Pasqua
- Department of Food Science, Division of Microbiology, University of Naples Federico II, Via Università 100, 80055 Portici, Italy
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28
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Di Pasqua R, Hoskins N, Betts G, Mauriello G. Changes in membrane fatty acids composition of microbial cells induced by addiction of thymol, carvacrol, limonene, cinnamaldehyde, and eugenol in the growing media. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2006; 54:2745-9. [PMID: 16569070 DOI: 10.1021/jf052722l] [Citation(s) in RCA: 281] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Major active compounds from essential oils are well-known to possess antimicrobial activity against both pathogen and spoilage microorganisms. The aim of this work was to determine the alteration of the membrane fatty acid profile as an adaptive mechanism of the cells in the presence of a sublethal concentration of antimicrobial compound in response to a stress condition. Methanolic solutions of thymol, carvacrol, limonene, cinnamaldehyde, and eugenol were added into growth media of Escherichia coli O157:H7, Salmonella enterica serovar typhimurium, Pseudomonas fluorescens, Brochothrix thermosphacta, and Staphylococcus aureus strains. Fatty acid extraction and gas chromatographic analysis were performed to assess changes in membrane fatty acid composition. Substantial changes were observed on the long chain unsaturated fatty acids when the E. coli and Salmonella strains grew in the presence of limonene and cinnamaldehyde and carvacrol and eugenol, respectively. All compounds influenced the fatty acid profile of B. thermosphacta, while Pseudomonas and S. aureus strains did not show substantial changes in their fatty acid compositions.
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Affiliation(s)
- Rosangela Di Pasqua
- Department of Food Science, Division of Microbiology, University of Naples Federico II, Via Università 100, 80055 Portici, Italy
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29
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Beales N. Adaptation of Microorganisms to Cold Temperatures, Weak Acid Preservatives, Low pH, and Osmotic Stress: A Review. Compr Rev Food Sci Food Saf 2004; 3:1-20. [DOI: 10.1111/j.1541-4337.2004.tb00057.x] [Citation(s) in RCA: 459] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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30
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Guerzoni ME, Lanciotti R, Cocconcelli PS. Alteration in cellular fatty acid composition as a response to salt, acid, oxidative and thermal stresses in Lactobacillus helveticus. MICROBIOLOGY (READING, ENGLAND) 2001; 147:2255-2264. [PMID: 11496002 DOI: 10.1099/00221287-147-8-2255] [Citation(s) in RCA: 192] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The fundamental question in this study is concerned with whether the increase of unsaturated fatty acids in the cell membrane is a general response of certain thermotolerant strains or species when exposed to superoptimal temperatures, and in combination with other stresses, especially oxidative stress. A strain of Lactobacillus helveticus, a species widely used as a starter in the dairy industry and able to tolerate high temperature and NaCl concentrations as well as acidic conditions, was chosen for this study. Cells of strain CNBL 1156, grown in its natural medium (i.e. milk whey), were exposed for 100 min to sublethal combinations of temperature, NaCl, H(2)O(2) and pH, modulated according to a Central Composite Design. The fatty acid composition of cell lipid extract was identified by GC/MS. Polynomial equations, able to describe the individual interactive and quadratic effects of the independent variables on cell fatty acid composition, were obtained. The results and the mathematical models relative to the individual fatty acids indirectly suggest that desaturase activation or hyperinduction play an important role in the response to heat stress. In fact, the relative proportions of oleic, linoleic and palmitic acids increased with temperature in a range between 38 and 54 degrees C. The fatty acid profiles included vernolic acid (up to 37% of total fatty acids), an epoxide of linoleic acid not previously reported in microbial cells. In particular, this epoxide was present in cells exposed to low pH in combination with high temperatures and oxidative stress. In conclusion, these results provide experimental support to the hypothesis that the increase of an oxygen-consuming desaturase system, with a consequent increase in fatty acid desaturation, is a cellular response to environmental stresses able to protect the cells of this anaerobic micro-organism from toxic oxygen species and high temperatures.
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Affiliation(s)
- M Elisabetta Guerzoni
- Dipartimento di Protezione e Valorizzazione Agroalimentare, University of Bologna, via S. Giacomo 7, 40126 Bologna, Italy1
| | - Rosalba Lanciotti
- Dipartimento di Protezione e Valorizzazione Agroalimentare, University of Bologna, via S. Giacomo 7, 40126 Bologna, Italy1
| | - P Sandro Cocconcelli
- Istituto di Microbiologia, Centro Ricerche Biotecnologiche, University Cattolica del Sacro Cuore Piacenza-Cremona, via Emilia Parmense 84, 29100 Piacenza, Italy2
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