Environmental Applications, Food and Biomass Processing by Pulsed Electric Fields

Frey, Wolfgang; Gusbeth, Christian; Sakugawa, Takashi; Sack, Martin; Mueller, Georg; Sigler, Juergen; Vorobiev, Eugène; Lebovka, Nikolaï; Álvarez, Ignacio; Raso, Javier; Heller, Loree C.; Malik, Muhammad Arif; Eing, C.; Teissié, Justin

doi:10.1007/978-4-431-56095-1_6

Cited by 14 publications

(11 citation statements)

References 272 publications

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“…Electroporation-based technologies extend to a growing number of applications including cancer treatment by electrochemotherapy, [6] genetic transformation of microorganisms as in gene therapy and DNA vaccination, [7] treatment of cardiac tissue and tumor ablation, [8] and microorganism inactivation as in wastewater treatment and food pasteurization. [9] All of these technologies rely on the formation of pores in the cell membranes. It remains a mystery however, why these pores have a wide range of lifetimes that can span from milliseconds to minutes [10] (or may not even close at all).…”

Section: Introductionmentioning

confidence: 99%

To Close or to Collapse: The Role of Charges on Membrane Stability upon Pore Formation

et al. 2021

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Resealing of membrane pores is crucial for cell survival. Membrane surface charge and medium composition are studied as defining regulators of membrane stability. Pores are generated by electric field or detergents. Giant vesicles composed of zwitterionic and negatively charged lipids mixed at varying ratios are subjected to a strong electric pulse. Interestingly, charged vesicles appear prone to catastrophic collapse transforming them into tubular structures. The spectrum of destabilization responses includes the generation of long‐living submicroscopic pores and partial vesicle bursting. The origin of these phenomena is related to the membrane edge tension, which governs pore closure. This edge tension significantly decreases as a function of the fraction of charged lipids. Destabilization of charged vesicles upon pore formation is universal—it is also observed with other poration stimuli. Disruption propensity is enhanced for membranes made of lipids with higher degree of unsaturation. It can be reversed by screening membrane charge in the presence of calcium ions. The observed findings in light of theories of stability and curvature generation are interpreted and mechanisms acting in cells to prevent total membrane collapse upon poration are discussed. Enhanced membrane stability is crucial for the success of electroporation‐based technologies for cancer treatment and gene transfer.

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Section: Introductionmentioning

confidence: 99%

To Close or to Collapse: The Role of Charges on Membrane Stability upon Pore Formation

et al. 2021

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“…Notably, the definition of EP has remained intact for over 30 years: EP is the transient loss of semi-permeability of cell membranes subjected to electric pulses, leading to ion leakage, escape of metabolites, and increased cell-uptake of drugs, molecular probes, or DNA [ 6 ]. This technology is nowadays widely used for other applications than solely DNA transfection, such as electrochemotherapy [ 11 , 12 ], cold EP [ 13 ], tissue ablation [ 1 , 14 ], intracellular delivery [ 15 ], extraction of various compounds [ 16 , 17 ], and in the food industry [ 18 , 19 , 20 , 21 ]. More recently, a following step in the application of electric pulses was the development of High Intensity Nano Pulsed Electric Fields technology, known in the scientific community as nanosecond Pulsed Electric Field (nsPEF) or Nano Pulse Stimulation (NPS).…”

Section: Introductionmentioning

confidence: 99%

Exploring the Conformational Changes Induced by Nanosecond Pulsed Electric Fields on the Voltage Sensing Domain of a Ca2+ Channel

et al. 2021

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Nanosecond Pulsed Electric Field (nsPEF or Nano Pulsed Stimulation, NPS) is a technology that delivers a series of pulses of high-voltage electric fields during a short period of time, in the order of nanoseconds. The main consequence of nsPEF upon cells is the formation of nanopores, which is followed by the gating of ionic channels. Literature is conclusive in that the physiological mechanisms governing ion channel gating occur in the order of milliseconds. Hence, understanding how these channels can be activated by a nsPEF would be an important step in order to conciliate fundamental biophysical knowledge with improved nsPEF applications. To get insights on both the kinetics and thermodynamics of ion channel gating induced by nsPEF, in this work, we simulated the Voltage Sensing Domain (VSD) of a voltage-gated Ca2+ channel, inserted in phospholipidic membranes with different concentrations of cholesterol. We studied the conformational changes of the VSD under a nsPEF mimicked by the application of a continuous electric field lasting 50 ns with different intensities as an approach to reveal novel mechanisms leading to ion channel gating in such short timescales. Our results show that using a membrane with high cholesterol content, under an nsPEF of 50 ns and E→ = 0.2 V/nm, the VSD undergoes major conformational changes. As a whole, our work supports the notion that membrane composition may act as an allosteric regulator, specifically cholesterol content, which is fundamental for the response of the VSD to an external electric field. Moreover, changes on the VSD structure suggest that the gating of voltage-gated Ca2+ channels by a nsPEF may be due to major conformational changes elicited in response to the external electric field. Finally, the VSD/cholesterol-bilayer under an nsPEF of 50 ns and E→ = 0.2 V/nm elicits a pore formation across the VSD suggesting a new non-reported effect of nsPEF into cells, which can be called a “protein mediated electroporation”.

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“…One of them employs membrane electroporation allowing for efficient delivery of materials, based on the application of one or more electric pulses. Electroporation-based technologies extend to a growing number of applications including cancer treatment by electrochemotherapy (8)(9)(10), genetic transformation of microorganisms as in gene therapy and DNA vaccination (11), treatment of cardiac tissue and tumor ablation (12), and microorganism inactivation as in waste-water treatment and food pasteurization (13). All of these technologies rely on the formation of pores in the cell membranes.…”

Section: Introductionmentioning

confidence: 99%

To close or to collapse: the role of charges on membrane stability upon pore formation

Lira

Leomil

Melo

et al. 2020

Preprint

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Resealing of membrane pores is crucial for cell survival. We studied the membrane surface charge and medium composition as defining regulators triggering bursting and collapse of giant unilamellar vesicles upon poration. The pores were generated by either electric field or a detergent. Vesicles composed of mixtures of zwitterionic and negatively charged lipids at varying molar ratios were subjected to a single strong electric pulse and their response was characterized for a given membrane and medium composition. We observe that charged vesicles are prone to catastrophic vesicle collapse transforming them into tubular structures. The spectrum of destabilization responses includes the generation of long-living submicroscopic pores and partial vesicle bursting. The origin of these phenomena is related to the membrane edge tension, which governs pore closure. This edge tension significantly decreases as a function of the molar fraction of charged lipids. Destabilization of charged vesicles upon pore formation is a universal process since it is also observed with other poration stimuli. Disruption propensity is enhanced for membranes made of lipids with higher degree of unsaturation. It can be reversed by screening membrane charge in the presence of calcium ions. We interpret the observed findings in light of theories of stability and curvature generation in charged membranes and discuss mechanisms acting in cells to prevent total membrane collapse upon poration. Enhanced membrane stability is crucial for the success of electroporation-based technologies for cancer treatment and gene transfer.Significance StatementLeaky membranes cannot support life. Cells have developed protective mechanisms to respond to pore formation in their membranes. We find that essential membrane components such as (asymmetrically distributed) charged lipids destabilize the membrane upon poration and lead to catastrophic collapse, shown here on giant unilamellar vesicles as model membranes porated either by electric fields or detergent. The charged lipids act via reducing the pore edge tension. The membrane destabilization can be reverted by calcium ions and is less pronounced for lipids with lower degree of unsaturation. The observed membrane stabilization can be employed for optimizing biotechnological developments employing electroporation for cancer treatment.

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Environmental Applications, Food and Biomass Processing by Pulsed Electric Fields

Cited by 14 publications

References 272 publications

To Close or to Collapse: The Role of Charges on Membrane Stability upon Pore Formation

To Close or to Collapse: The Role of Charges on Membrane Stability upon Pore Formation

Exploring the Conformational Changes Induced by Nanosecond Pulsed Electric Fields on the Voltage Sensing Domain of a Ca2+ Channel

To close or to collapse: the role of charges on membrane stability upon pore formation

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