The fact that bacteria can have sex has been known for around 70 years - if we define the term "sex" broadly enough. In addition to their conventional ring-shaped chromosome, many bacteria contain other small DNA rings, the plasmids. These often contain predispositions for abilities that offer advantages under special environmental conditions - for example, antibiotic resistance. Bacteria have developed a special technique to pass on these properties: On contact with another bacterial cell, they can duplicate the plasmid, form a tube-like extension - the "sex pili" - and transfer the plasmid DNA via it. This process is unromantically called "conjugation". This is how bacteria can exchange data. Any adaptive advantage that seems to make sense can spread everywhere. From a genetic point of view, this makes bacteria a giant communicating organism - tiny, very fast and therefore invincible. In 2001, American researchers even caught bacterial cells in flagrante delicto with hamster cells: the bacteria had transferred parts of their genetic material to the animal cells by exchanging characteristics via this "horizontal gene transfer".

© Susanne Thiele, Texcerpt changed to "Ask your door handle about risks and side effects. How microbes determine our everyday lives - new and astonishing facts about our versatile flatmates", Heyne 2019susanne_thiele[at]gmx.de
Figure: Isabel Klett