A NASA-supported research team has discovered a species of amoeba, Incendiamoeba cascadensis, that thrives in the high-temperature waters of California’s Lassen Volcanic National Park. The organism, nicknamed the “fire amoeba,” has set a new record for the highest temperature tolerance ever documented for a eukaryote—a category of life characterized by complex cells containing a nucleus.
According to the study published in the journal Cell, I. cascadensis is capable of reproducing at temperatures as high as 145 degrees Fahrenheit (63 degrees Celsius). While reproduction ceases above this point, the amoeba remains active and continues to forage for food in environments reaching 147 degrees Fahrenheit (64 degrees Celsius). This discovery challenges long-standing scientific assumptions that eukaryotic membrane structures and organelles could not remain stable above 144 degrees Fahrenheit (62 degrees Celsius).
Lead author Beryl Rappaport, a graduate student at Syracuse University, noted that the team identified specific genetic strategies used by the amoeba to survive, including proteins with high positive surface charges that maintain stability under heat stress. The researchers also identified similar DNA sequences in geothermal samples from Yellowstone National Park and New Zealand, suggesting that related thermophilic amoebas may exist globally.
Astrobiologists are interested in these findings because they expand the known boundaries for complex life. By studying how organisms endure extreme conditions on Earth, scientists can better refine the criteria used to search for life on other planets. However, researchers caution that temperature is only one factor; for complex life to persist, other environmental requirements such as oxygen, acidity, and nutrient availability must also be met.
Source: NASA
暂无评论。快来发表第一条评论吧。