As we found out today, all living beings are made up of six components: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. All living beings that is, until GFAJ-1. This little guy uses arsenic as its building blocks instead of the usual maple or walnut used by humans. This information is very valuable to scientists, who will now know to look for poison in addition to the usual DNA materials when searching for new life on Earth and abroad.
GFAJ-1 at 5 micrometers, looking suspiciously like Rice KrispiesAccording to NASA's Ed Weiler, "The definition of life has just expanded." According to the European Union's directive 67/548/EEC, "Elemental arsenic and arsenic compounds are classified as 'toxic' and 'dangerous for the environment.'" This is all very exciting!