The amoeba was discovered at a hot spring in California’s Lassen Volcanic National Park.
Credit: Dukas/Getty Images
A newly discovered single-cell amoeba has broken the temperature record for eukaryotic organisms with a cell wall and an internal cell nucleus, reports a new paper in Nature. The aptly named Incendiamoeba cascadensis (translation: “fire amoeba from the cascades”) was able to tolerate surrounding water temperatures of up to 63 degrees Celsius (145.4 Fahrenheit) and still reproduce. It entered a dormant (but recoverable) state at 70 degrees C (158 F), blowing right past the previous record of 60 degrees.
Angela Oliverio and fellow Syracuse microbiologist Beryl Rappaport discovered the amoeba at Lassen Volcanic National Park in northern California’s Cascade mountain range. When sampling from a hot stream, the researchers observed the amoeba growing at 57 degrees C, a temperature it typically encounters in natural streams. They then raised the temperature further to 60, 64, and even 70 degrees C, and the amoeba was completely fine.
Credit: Natalie Petek-Seoane from the preprint by H. Beryl Rappaport et al./bioRxiv
Bacteria can typically survive temperatures far in excess of what organisms with cell walls and nuclei can manage, but this fire amoeba bucks the trend and was still reproducing well in excess of temperatures that would cause devastating harm to most multicelled organisms. Although it doesn’t come close to the 122-degree record for bacteria to reproduce, it’s still well in excess of what human beings and animals can manage, and a real leap from the previous fungal record holders.
Such discoveries are not only academically interesting; they also fundamentally change our understanding of what these kinds of eukaryotes are capable of. If they can manage these kinds of high temperatures, what other conditions might they survive in? These kinds of hyper-capable creatures could hold the secrets to future drug development and help guide the search for extraterrestrial life.
As the scientists also point out, they examined only one stream in this extreme environment. What are the chances they found the only interesting amoeba there? It sounds like they’ll be back soon to see what else is just waiting to be discovered.