An article published in the journal “Cell Host & Microbe” reports the results of a study on the widespread symbiosis between predatory protists and bacteria related to species that are pathogenic to various animal species and sometimes to humans. A team of researchers led by scientists from the Marine Biological Laboratory (MBL) conducted a series of analyses on water samples collected at the surface of the Pacific Ocean, the Caribbean Sea, and the North Atlantic and identified protists that have predatory habits that eat some species of bacteria but are in symbiosis with other species. The results suggest a long and complex history of relationships that sometimes are symbiosis and sometimes are parasitism by bacteria with animals and choanoflagellates, the closest relatives of animals among eukaryotes.

An article published in the journal “Cell” reports the results of the use of genetic manipulation to study the behavior of some bacteria belonging to a large group called Patescibacteria. A team of researchers managed to manipulate the DNA of bacteria belonging to the phylum Saccharibacteria, which is part of that large group, which is considered microbial dark matter for the difficulties biologists had in studying them. These are bacteria discovered not many years ago that are now considered interesting for their metabolic characteristics, which for example, may include enzymes useful in biotechnological applications.

An article published in the journal “Science” reports the identification of a bacterium that can reach two centimeters in length, a size that is several thousand times larger than those of most bacteria. A team of researchers named it Thiomargarita magnifica after discovering it in the Guadeloupe archipelago in the Lesser Antilles. It took years to understand its nature because the size, gigantic for a bacterium, and some unusual characteristics for this type of organism initially suggested that it was a multicellular organism, perhaps a fungus.