Electrical spiking in bacterial biofilms.
In nature, biofilms are the most common form of bacterial growth. In biofilms, bacteria display coordinated behaviour to perform specific functions. Here, we investigated electrical signalling as a possible driver in biofilm sociobiology. Using a multi-electrode array system that enables high spatio-temporal resolution, we studied the electrical activity in two biofilm-forming strains and one non-biofilm-forming strain. The action potential rates monitored during biofilm-forming bacterial growth exhibited a one-peak maximum with a long tail, corresponding to the highest biofilm development. This peak was not observed for the non-biofilm-forming strain, demonstrating that the intensity of the electrical activity was not linearly related to the bacterial density, but was instead correlated with biofilm formation. Results obtained indicate that the analysis of the spatio-temporal electrical activity of bacteria during biofilm formation can open a new frontier in the study of the emergence of collective microbial behaviour.
DISPAA-Department of Agrifood and Environmental Science, University of Florence, Florence, Italy.
Elisa
E
Masi
DISPAA-Department of Agrifood and Environmental Science, University of Florence, Florence, Italy CNR-Istituto Nazionale di Ottica, Florence, Italy.
Marzena
M
Ciszak
DISPAA-Department of Agrifood and Environmental Science, University of Florence, Florence, Italy.
Luisa
L
Santopolo
DISPAA-Department of Agrifood and Environmental Science, University of Florence, Florence, Italy.
Arcangela
A
Frascella
DISPAA-Department of Agrifood and Environmental Science, University of Florence, Florence, Italy.
Luciana
L
Giovannetti
DISPAA-Department of Agrifood and Environmental Science, University of Florence, Florence, Italy.
Emmanuela
E
Marchi
DISPAA-Department of Agrifood and Environmental Science, University of Florence, Florence, Italy carlo.viti@unifi.it.
Carlo
C
Viti
DISPAA-Department of Agrifood and Environmental Science, University of Florence, Florence, Italy.
Stefano
S
Mancuso
D000200:Action Potentials; D001407:Bacillus; D001419:Bacteria / Q000378:metabolism*; D018407:Bacterial Physiological Phenomena; D018441:Biofilms; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D004926:Escherichia coli; D046228:Microarray Analysis; D011108:Polymers / Q000737:chemistry; D011549:Pseudomonas; D015398:Signal Transduction; D013696:Temperature
D011108:Polymers
bacteria; biofilm; electrical spiking; multi-electrode array; sociobiology