Microbiologists: B. subtilis produces SOUND!!
Are you aware that B. subtilis, and some other microbes,
while being cultured, actually puts out SOUND??
According to the article, reference attached, this sound is
loudest at about 25 kilohertz, which is well above the
frequency limit of human hearing. We will FAX you a copy
of this article, if you desire.
It is possible that the best way to monitor growth of B.
subtilis is by "listening in" to this sound. According to the
article, the cells use this sound for communication
Potential applications abound. Is it possible, for instance,
to characterize microfauna by their ultrasonic output ? Can
a "spectrum analysis" tool be developed to quantitatively
identify the various components of a mixed culture ? Such
a tool might resemble the "mass spectrometers" so useful
to Chemists. In medicine, does a healthy/sick organ present
different ultrasonic signatures?
We are prepared to offer you a complete system for
listening to the B. subtilis grow for $995.00. This
system consists of a submersible ultrasonic transducer
and an ultrasonic receiver. The receiver converts the
high-frequency sound from B. subtilis to a lower
frequency sound which you can hear.
If you desire to get in on this exciting new field of micro-
biological measurement, please contact me.
Henry C. Wallace, Physicist
Director of Research
Ultrasonic Energy Systems: Building near
megahertz high-intensity ultrasonic sources...
Please visit us at:
Vol 44, Issue 1, Feb. 1998, JOURNAL OF GENERAL
AND APPLIED MICRO-BIOLOGY, Publishers
MICROBIOLOGY RESEARCH FOUNDATION,
Tokyo, Japan, pages 49-55.
Title "Production of sound waves by bacterial cells and
the response of bacterial cells to sound"
Author: M Matsuhashi, Tokai University
Department of Biological Science & Technology
317 Nishino, Shizuoka 4100321, Japan
Bacterial cells enhance the proliferation of neighboring
cells under stress conditions by emitting a physical
signal. Continuous single sine sound waves produced
by a speaker at frequencies of 6-10, 18-22, and 28-38
kHz promoted colony formation by Bacillus carboniphilus
under non-permissive stress conditions of high KCl
concentration and high temperature. Furthermore, sound
waves emitted from cells of Bacillius subtilis at frequencies
between 8 and 43 kHz with broad peaks at approximately
8.5, 19, 29, and 37 kHz were detected using a sensitive
microphone system. The similarity between the frequency of
the sound produced by B. subtilis and the frequencies that
induced a response in B. carboniphilus and the previously
observed growth-promoting effect of B. subtilis cells upon
B. carboniphilus through iron barriers, suggest that the
detected sound waves function as a growth-regulatory
signal between cells.