The legionella germs, which triggers Legionnaires disease, comes from a large group of germs called Legionellales. All Legionellales germs can infect eukaryotic hosts: amoebas, insects, or our own cells.
Lionel Guy, associate professor of evolutionary microbiology at the Department of Medical Biochemistry and Microbiology, Uppsala University. Credit: Sanna Dovat Guy
” We discovered that the ancestor of the entire group lived about 2 billion years back, at a time when eukaryotes were still in the making, progressing from simpler cells to the intricate cell structure they have now,” says Andrei Guliaev, a researcher at the Department of Medical Biochemistry and Microbiology. “We believe Legionellales were among the very first to infect eukaryotic cells.”
The first action in an infection with legionella bacteria is for a eukaryotic host, such as an amoeba, to bring the germs into its cell through a procedure called phagocytosis. The next step for the amoeba would be to digest the bacterium and utilize its parts as an energy source. Legionella bacteria have molecular tools that keep them from being digested and permit them to rather utilize the amoeba as an energy source so they can multiply.
In the study, the researchers reveal that all Legionellales have the very same sort of molecular tools as legionella. That suggests that the ability to contaminate eukaryotes already existed in the ancestor of all Legionellales. This implies that phagocytosis is at least as old as Legionellales– two billion years of ages– when eukaryotes remained in the early stages of their advancement.
Was it the mitochondria, which stemmed from another group of bacteria and became our cells own energy factories? Or was it phagocytosis, which is considered essential to take in mitochondria but is very expensive from an energy standpoint?
” Some scientists think that mitochondria were needed to deliver enough energy for phagocytosis to work. However our results suggest that phagocytosis preceded– two billion years ago– while mitochondria came later on,” says Lionel Guy.
Recommendation: “Host-adaptation in Legionellales is 1.9 Ga, coincident with eukaryogenesis” by Eric Hugoson, Andrei Guliaev, Tea Ammunét and Lionel Guy15 February 2022, Molecular Biology and Evolution.DOI: 10.1093; 10.1093/ molbev/msac037.
Legionella germs illustration.
Scientists at Uppsala University have actually found that the forefathers of legionella bacteria infected eukaryotic cells as early as two billion years ago. It happened quickly after eukaryotes started to feed upon germs. These results, explained in a brand-new study released in Molecular Biology and Evolution, likewise contributes to the chicken-or-egg debate about whether mitochondria or phagocytosis came.
” Our research study can help us understand how damaging bacteria arise and how complicated cells progressed from simpler cells,” states Lionel Guy, associate teacher of evolutionary microbiology at the Department of Medical Biochemistry and Microbiology, who headed the research study.
Two billion years ago, forefathers of legionella germs currently had the capability to prevent being digested by eukaryotes. Instead, they started using eukaryotic cells– complex cells with a nucleus that comprise amoebas, fungis and human beings– to increase.
Scientists at Uppsala University have actually found that the ancestors of legionella germs infected eukaryotic cells as early as 2 billion years back. The very first action in an infection with legionella bacteria is for a eukaryotic host, such as an amoeba, to bring the bacterium into its cell through a procedure called phagocytosis. Legionella bacteria have molecular tools that keep them from being absorbed and permit them to instead utilize the amoeba as an energy source so they can increase.
Was it the mitochondria, which originated from another group of germs and became our cells own energy factories?
