Chapter 21
Electrotransformation of Saccharomyces cerevisiae
E. Meilhoc and J. Teissie
Abstract
Intact yeast cell transformation is easily achieved by gene electrotransfer (GET). The procedure is fast and
efficient in terms of transformants/μg DNA. Yeast cells in exponential growth phase are washed, treated for
a short period with dithiothreitol (DTT) and then mixed with the plasmid DNA in a buffer with a low
conductivity. A single well defined electric pulsed is delivered. After a 1 h incubation in the growth medium
without selection, transformants are obtained on a selective plate medium. After a short description of the
present knowledge on the events affecting the yeast cell as a consequence of the pulsed electric field, a stepby-step protocol is reported for Saccharomyces cerevisiae.
Key words Yeast, Saccharomyces, Electrotransformation, Gene electrotransfer
1 Introduction
Yeast transformation has started to be possible in the 1980s mainly
on Saccharomyces cerevisiae. Two different approaches were developed. The first one called the spheroplast method was based on the
removal of the yeast cell wall by enzymatic treatment to yield
protoplasts [1]. The transformation efficiency was rather good
but the method was time-consuming as protoplast preparation
and regeneration were needed. In addition, the protocol could
vary from one strain to another depending upon their cell wall
composition. The second approach relied on intact yeast cell transformation using either a chemical method (treatment by LiCl) [2]
or a mechanical approach using shaking with glass beads [3]. These
transformation methods were rapid but showed a very low efficiency. In 1989–1990, several reports described a gene electrotransfer (GET) approach [4–7]. This approach was simple, very
fast, and highly efficient [7, 8]. In addition, its cost was low when
a suitable electric pulse generator was available. Yeast cells were
washed in a low conductivity pulsing buffer. In a few cases, polyethylene glycol (PEG) and/or carrier DNA were added
[9, 10]. Plasmid DNA (pDNA) was added and an electric voltage
Shulin Li et al. (eds.), Electroporation Protocols: Microorganism, Mammalian System, and Nanodevice,
Methods in Molecular Biology, vol. 2050, https://doi.org/10.1007/978-1-4939-9740-4_21,
© Springer Science+Business Media, LLC, part of Springer Nature 2020
187
Electrotransformation of Saccharomyces cerevisiae
E. Meilhoc and J. Teissie
Abstract
Intact yeast cell transformation is easily achieved by gene electrotransfer (GET). The procedure is fast and
efficient in terms of transformants/μg DNA. Yeast cells in exponential growth phase are washed, treated for
a short period with dithiothreitol (DTT) and then mixed with the plasmid DNA in a buffer with a low
conductivity. A single well defined electric pulsed is delivered. After a 1 h incubation in the growth medium
without selection, transformants are obtained on a selective plate medium. After a short description of the
present knowledge on the events affecting the yeast cell as a consequence of the pulsed electric field, a stepby-step protocol is reported for Saccharomyces cerevisiae.
Key words Yeast, Saccharomyces, Electrotransformation, Gene electrotransfer
1 Introduction
Yeast transformation has started to be possible in the 1980s mainly
on Saccharomyces cerevisiae. Two different approaches were developed. The first one called the spheroplast method was based on the
removal of the yeast cell wall by enzymatic treatment to yield
protoplasts [1]. The transformation efficiency was rather good
but the method was time-consuming as protoplast preparation
and regeneration were needed. In addition, the protocol could
vary from one strain to another depending upon their cell wall
composition. The second approach relied on intact yeast cell transformation using either a chemical method (treatment by LiCl) [2]
or a mechanical approach using shaking with glass beads [3]. These
transformation methods were rapid but showed a very low efficiency. In 1989–1990, several reports described a gene electrotransfer (GET) approach [4–7]. This approach was simple, very
fast, and highly efficient [7, 8]. In addition, its cost was low when
a suitable electric pulse generator was available. Yeast cells were
washed in a low conductivity pulsing buffer. In a few cases, polyethylene glycol (PEG) and/or carrier DNA were added
[9, 10]. Plasmid DNA (pDNA) was added and an electric voltage
Shulin Li et al. (eds.), Electroporation Protocols: Microorganism, Mammalian System, and Nanodevice,
Methods in Molecular Biology, vol. 2050, https://doi.org/10.1007/978-1-4939-9740-4_21,
© Springer Science+Business Media, LLC, part of Springer Nature 2020
187