Bacterial Exchange via Nanotubes: Lessons Learned from the History of Molecular Biology

Thomas A. Ficht

DNA transfer between bacteria has a long and storied history. Starting shortly after the discovery by Avery, MacLeod, and McCarty that DNA was the genetic material, the exchange of DNA between bacteria confirmed that DNA transfer could stably change the phenotypic behavior of organisms. Continued effort along these lines led to the discovery of conjugation systems, bacteriophage transduction, bacterial genome mapping, and to some represents the birth of molecular biology. Recent findings by Dubey and Ben-Yehuda (2011) expand on these early results by suggesting that exchange between bacteria may occur continuously under certain growth conditions via nanotubes. These nanotubes have a structure similar to cell membranes and are sensitive to mild detergent treatment. Transfer of protein and plasmid DNA was demonstrated directly between neighboring and distant bacteria of the same and different genera. Transfer of RNA cannot be ruled out and the transfer of chromosomal DNA was not addressed. This work may reveal an important mechanism behind the spread of antibiotic resistance, however, much work remains to be done in order to confirm or refute the role of this mechanism in the dangerous spread of antibiotic resistance within the prokaryotic biosphere. The work of early molecular biology pioneers can be used as inspiration, if not as a direct template to guide future experimental confirmation.