Electric field‐induced effects on yeast cell wall permeabilization

Abstract

The permeability of the yeast cells (Saccharomyces cerevisiae) to lipophilic tetraphenylphosphonium cations (TPP(+) ) after their treatment with single square-shaped strong electric field pulses was analyzed. Pulsed electric fields (PEF) with durations from 5 to 150 µs and strengths from 0 to 10 kV/cm were applied to a standard electroporation cuvette filled with the appropriate buffer. The TPP(+) absorption process was analyzed using an ion selective microelectrode (ISE) and the plasma membrane permeability was determined by measurements obtained using a calcein blue dye release assay. The viability of the yeast and the inactivation of the cells were determined using the optical absorbance method. The experimental data taken after yeasts were treated with PEF and incubated for 3 min showed an increased uptake of TPP(+) by the yeast. This process can be controlled by setting the amplitude and pulse duration of the applied PEF. The kinetics of the TPP(+) absorption process is described using the second order absolute rate equation. It was concluded that the changes of the charge on the yeast cell wall, which is the main barrier for TPP(+) , is due to the poration of the plasma membrane. The applicability of the TPP(+) absorption measurements for the analysis of yeast cells electroporation process is also discussed.

Compact Square-Wave Pulse Electroporator with Controlled Electroporation Efficiency and Cell Viability

“…This result is very important for performing electroporation and retaining a high viability of the treated cells. Our previous study showed that the detectable electroporation in yeast cells starts after exposure to 5-µs pulses with an electric field strength of approximately 5 kV/cm [37]. Such an electric field corresponds to a 500-V amplitude (dashed line in Figure 7) and such an electric field strength or higher remained for 8.4 µs and 5.5 µs when generated by systems without and with the crowbar circuit, respectively.…”

Yeast cell disruption strategies for recovery of intracellular bio-active compounds — A review

“…It is easy to release only periplasmic space material (recombinant protein) through the pores, while the co-release of contaminants and micronization of the cell debris can be minimized, which offer advantages for the subsequent purification. Besides, Stirke et al (2014Stirke et al ( , 2014a investigated the yeast cell walls disruption using nanosecond high power electrical pulses. Ganeva, Stefanova and Angelova (2015) achieved the selective and efficient recovery of large intracellular proteins from yeast based on the combination of electropermeabilisation and subsequent treatment with lytic enzyme.…”

Analysis of Planar Circular Interdigitated Electrodes for Electroporation

“…Typically, substances such as fluorescent dyes are loaded into the cells [11,12]. The cells are put into a cuvette with electrodes and after pulsing procedures the release or loading of the dye is observed [13,14].…”