Electric polarization properties of single bacteria measured with electrostatic force microscopy
| Autor: | Laura Fumagalli, Antonio Juárez, Martin A. Edwards, Daniel Esteban-Ferrer, Gabriel Gomila |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Microscopy
biology Chemistry Electrostatic force microscope Static Electricity General Engineering Analytical chemistry food and beverages General Physics and Astronomy Dielectric biology.organism_classification Bacterial Physiological Phenomena Bacterial cell structure Polarization density parasitic diseases Listeria General Materials Science Bacterial types Polarization (electrochemistry) Bacteria |
| Zdroj: | ACS nano. 8(10) |
| ISSN: | 1936-086X |
| Popis: | We quantified the electrical polarization properties of single bacterial cells using electrostatic force microscopy. We found that the effective dielectric constant, ε(r,eff), for the four bacterial types investigated (Salmonella typhimurium, Escherchia coli, Lactobacilus sakei, and Listeria innocua) is around 3-5 under dry air conditions. Under ambient humidity, it increases to ε(r,eff) ∼ 6-7 for the Gram-negative bacterial types (S. typhimurium and E. coli) and to ε(r,eff) ∼ 15-20 for the Gram-positive ones (L. sakei and L. innocua). We show that the measured effective dielectric constants can be consistently interpreted in terms of the electric polarization properties of the biochemical components of the bacterial cell compartments and of their hydration state. These results demonstrate the potential of electrical studies of single bacterial cells. |
| Databáze: | OpenAIRE |
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