‘Fire โAmoeba’ โShatters Heat Tolerance Record for โคComplex Life
LASSEN โขVOLCANIC NATIONAL PARK, CA – A newly discoveredโ amoeba, โฃ Incendiamoeba cascadensis, is challenging long-held assumptions about the limits of life, thriving โat temperatures previously considered lethal for complex, eukaryotic โฃcells. The single-celled organism, found in a seemingly unremarkable hot stream within Lassen Volcanic National Park in northern California, can survive adn reproduce at 63ยฐC (145ยฐF) and remain active at 64ยฐC (147ยฐF), surpassing the previous recordโ of 60ยฐC for eukaryotes – organisms with cells containing a nucleus and internal structures.
The discovery, detailed in a preprint published November 24th, suggests a basic need to โreassess the potential forโค complex life to exist in extreme environments.”we need to โrethink โคwhat’s possible for a eukaryotic cell in a significant way,” says Angela Oliverio,โ a microbiologist at Syracuse university in New York, and a member of the research team.
I. cascadensis, translating to ‘fire amoeba โฃfrom the cascades,’ was identified by oliverioโ andโ fellow Syracuse microbiologist Beryl Rappaport.Despite initial microscopic examinations of water samples appearing lifeless, culturing revealed the amoeba’s presence and remarkable heat tolerance. Researchers observed the organism not only dividing โขat โคunprecedented โtemperatures but also forming resilient dormant cysts capable of reactivationโ even after exposure to 70ยฐC (158ยฐF).
This finding raisesโฃ questions about โฃthe evolutionary adaptations that โallow I. โcascadensis toโ flourish inโค such โคconditions and could have implicationsโ for understanding theโข potentialโค for lifeโฃ in other extreme environments, both โฃon Earthโค and โขbeyond. Lassen Volcanic National Park,known for its geothermal features,providedโ an unexpectedโข home for this groundbreaking discovery. “it’s the most uninteresting geothermal feature you’ll find in Lassen,” notes Rappaport, highlighting the unassuming nature of the stream where the โข’fire amoeba’ was found.
