The first organism able to substitute one of the six chemical elements crucial to life has been found.
The bacterium, found in a California lake, uses the usually poisonous element arsenic in place of phosphorus.
The find, described in Science, gives weight to the long-standing idea that life on other planets may have a radically different chemical makeup.
It also has implications for the way life arose on Earth – and how many times it may have done so.
The “extremophile” bacteria were found in a briny lake in eastern California in the US.
While bacteria have been found in inhospitable environments and can consume what other life finds poisonous, this bacterial strain has actually taken arsenic on board in its cellular machinery.
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