Has NASA discovered extraterrestrial life? • Hacker News Board

electromagnetic wrote: post #8

dotBen wrote: post #6

Earlier quoted context omitted.

During 'regular' photosynthesis water (H2O) is broken down during Oxygen Evolving Complex to leave the individual atoms (H and O) along with protons and electrons which fuel photosynthesis. The idea behind the arsenic theory is that arenate, which has 4 O atoms, could provide act as a suitable substrate during Oxygen Evolving Complex to provide the same protons and electron break down. There is also a parallel chain…

Arsenic is only toxic to our understanding of biology. Some extremophiles have unbelievable resistance to heavy metals, so I wouldn't doubt some configuration of our biology would be resistant to arsenic. However, with the problems arsenic causes blocking PDH enzyme, causing H2O2 in the cells and a huge list else like IIRC thiamine deficiency. Then again, life exists in such a broad range of conditions that I find it…

In retrospect, this is priceless...