New Worlds: Catching a ride with bacteria

New research conducted in Israel and the Netherlands lookes at new strategies of cooperation between bacteria, fungi.

By JUDY SIEGEL-ITZKOVICH
resistant bacteria 311 (photo credit: Courtesy)
resistant bacteria 311
(photo credit: Courtesy)
Arich variety of microorganisms – mainly bacteria and fungi – co-colonize the soil environment surrounding plant roots (a narrow region of soil called the rhizosphere that contains many bacteria feeding on sloughed-off plant cells. To thrive in this heterogeneous and highly competitive habitat, microorganisms developed a gamut of advanced and sophisticated strategies for cooperation and competition with other species. New research conducted in Israel and the Netherlands looked at new strategies of cooperation between bacteria and fungi.
Prof. Eshel Ben-Jacob of Tel Aviv University, with his master’s student Oren Kalishman and his post-doctoral fellow Dr. Alin Finkelshtein, collaborated on the research with Dr. Colin Ingham of Wageningen University. Ironically, Ben-Jacob is a senior astrophysicist who spends much of his time on the physical universe and subjects like “black holes,” but he has also been studying social behaviors of bacteria for over two decades. His motivation, he says, is to understand what are the fundamental differences between non-living and living systems.
The new study discovered special strategic cooperation between fungi and social bacteria. Fungal spores, he explains, can be rescued from dangerous locations by “hitching a ride” on swarms of bacteria. In return, the bacteria use the fungal mycelia, the vegetative part of a fungus, consisting of a mass of branching, thread-like structure as natural bridges to cross impenetrable gaps in the soil.
As a result of their work, bacteria are now recognized as “smart organisms” conducting intricate social life manifested by swarming and their ability to develop large, complex colonies. The astonishing observations in this article provide an additional intriguing example of how smart bacteria really are and how special the species they worked on, which is called P. vortex, is. The observations can also be relevant to agriculture and medicine as they show new mechanisms by which bacteria and fungi can aid each other to invade new territories in the rhizosphere, in hospitals and within the human body.
It is known that motile bacteria can carry cargo and can even perform mechanical tasks, says Ingham. This motivated the team to see if there are bacteria that have “high social intelligence.” In the recent article published recently in the Proceedings of the National Academy of Science, the researchers showed that the pattern-forming bacteria called P. vortex and non-motile Aspergillus fumigates fungus aid each other’s dispersal: swarms of P. vortex can transport the fungal spores over very long distances (tens of centimeters – equivalent to tens of kilometers in human scale) and at a very high rate (jet-plane speed in human scale).
In addition, the bacteria can rescue fungal spores from life-threatening locations, transporting them to new and favorable places where the spores can germinate and develop new flourishing colonies. The authors suggest the bacteria entrap with their armlike- structures and tie the spores that cannot move; the result reminds Ben-Jacob of the way the Lilliputians moved the giant Gulliver.
“Being aware of how smart bacteria are, we expected that the bacteria get something in return,” he adds.
SILVER ANNIVERSARY FOR HADASIT The 25th anniversary of Hadasit Ltd., the technology transfer company of the Hadassah Medical Organization, celebrated the event with a recent gathering of over 150 businessmen and biomedical researchers at Hadassah University Medical Center in Jerusalem’s Ein Kerem.
While physicians once were ashamed to talk about making money from their medical discoveries, today, the importance of developing new medications and medical equipment and applying them at the bedside is highly accepted. In recent years, due to the economic situation around the world, international pharmaceutical companies have been reducing the number of experimental medications they develop and study, thus fewer drugs are brought to market. Hadasit is hungry for those that will bring it foward, said its chairman, Prof. Shlomo Mor-Yosef. Of the 4,000 hi-tech companies in Israel, about a quarter are biotech companies.
Hadasit director Dr. Einat Zisman mentioned a number of its intellectual properties, including the chemotherapy drug Doxil and Periochip for periodontal disease. As biomedical researchers are so busy with their clinical work and usually have little expertise in clinical trials, production and the business side, Hadasit takes the responsibility for these.