2018/07/03 by Thiruvallur R. Gowrishankar, Julie Stern, Gowrishankar, Thiruvallur R. +5
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · Engineering · #FOS: Biological sciences #Microbial Inactivation Methods #Microfluidic and Bio-sensing Technologies #Plant Genetic and Mutation Studies #Subcellular Processes (q-bio.SC)
paper · pdf · doi:10.48550/arxiv.1807.00977
openalex publication_date 2018/07/03 · openalex created_date 2022/08/04 · openalex updated_date 2026/07/28
Extraordinarily large but short electric field pulses are reported by many\nexperiments to cause bipolar cancellation (BPC). This unusual cell response\noccurs if a first pulse is followed by a second pulse with opposite polarity.\nPossibly universal, BPC presently lacks a mechanistic explanation. Multiple\nversions of the "standard model" of cell electroporation (EP) fail to account\nfor BPC. Here we show, for the first time, how an extension of the standard\nmodel can account for a key experimental observation that essentially defines\nBPC: the amount of a tracer that enters a cell, and how tracer influx can be\ndecreased by the second part of a bipolar pulse. The extended model can also\naccount for the recovery of BPC wherein the extent of BPC is diminished if the\nspacing between the first and second pulses is increased. Our approach is\nreverse engineering, meaning that we identify and introduce an additional\nbiophysical mechanism that allows pore transport to change. We hypothesize that\noccluding molecules from outside the membrane enter or relocate within a pore.\nSignificantly, the additional mechanism is fundamental and general, involving a\ncombination of partitioning and hindrance. Molecules near the membrane can\nenter pores to block transport of tracer molecules while still passing small\nions (+/- 1) that govern electrical behavior. Accounting for such behavior\nrequires an extension of the standard model.\n