Ancestors of Legionella Bacteria Infected Cells Two Billion Years Ago
Published:21 Feb.2022 Source:Uppsala University
“Our study can help us understand how harmful bacteria arise and how complex cells evolved from simpler cells,” says Lionel Guy, associate professor of evolutionary microbiology at the Department of Medical Biochemistry and Microbiology, who headed the study. Two billion years ago, ancestors of legionella bacteria already had the ability to avoid being digested by eukaryotes. Instead, they began using eukaryotic cells -- complex cells with a nucleus that make up amoebas, fungi and human beings -- to multiply.
The legionella bacterium, which causes Legionnaires’ disease, belongs to a large group of bacteria called Legionellales. All Legionellales bacteria can infect eukaryotic hosts: amoebas, insects or our own cells. “We discovered that the ancestor of the whole group lived about two billion years ago, at a time when eukaryotes were still in the making, evolving from simpler cells to the complex cell structure they have now,” says Andrei Guliaev, a researcher at the Department of Medical Biochemistry and Microbiology. “We believe Legionellales were among the first to infect eukaryotic cells.”