F. David and M. Hebeisen contributed equally to this work.
Viability and membrane potential analysis of Bacillus megaterium cells by impedance flow cytometry†
Article first published online: 17 OCT 2011
Copyright © 2011 Wiley Periodicals, Inc.
Biotechnology and Bioengineering
Volume 109, Issue 2, pages 483–492, February 2012
How to Cite
David, F., Hebeisen, M., Schade, G., Franco-Lara, E. and Di Berardino, M. (2012), Viability and membrane potential analysis of Bacillus megaterium cells by impedance flow cytometry. Biotechnol. Bioeng., 109: 483–492. doi: 10.1002/bit.23345
- Issue published online: 12 DEC 2011
- Article first published online: 17 OCT 2011
- Accepted manuscript online: 28 SEP 2011 08:06AM EST
- Manuscript Accepted: 12 SEP 2011
- Manuscript Revised: 18 AUG 2011
- Manuscript Received: 22 MAR 2011
- Deutsche Forschungsgemeinschaft
- metabolic activity;
- membrane integrity;
- transition states
Single cell analysis is an important tool to gain deeper insights into microbial physiology for the characterization and optimization of bioprocesses. In this study a novel single cell analysis technique was applied for estimating viability and membrane potential (MP) of Bacillus megaterium cells cultured in minimal medium. Its measurement principle is based on the analysis of the electrical cell properties and is called impedance flow cytometry (IFC). Comparatively, state-of-the-art fluorescence-based flow cytometry (FCM) was used to verify the results obtained by IFC. Viability and MP analyses were performed with cells at different well-defined growth stages, focusing mainly on exponential and stationary phase cells, as well as on dead cells. This was done by PI and DiOC2(3) staining assays in FCM and by impedance measurements at 0.5 and 10 MHz in IFC. In addition, transition growth stages of long-term cultures and agar plate colonies were characterized with both methods. FCM and IFC analyses of all experiments gave comparable results, quantitatively and qualitatively, indicating that IFC is an equivalent technique to FCM for the study of physiological cell states of bacteria. Biotechnol. Bioeng. 2012; 109:483–492. © 2011 Wiley Periodicals, Inc.