A thought provoking idea.

[imposterzill]

I have heard of that it is possible that there could be arsenic, sulphur, and iron based life. How could these, especially the two latter ones be possible? Just curious, need information on how this could occur.

[YT2095]

This doesn`t belong in Organic Chemistry.

 

*thread moved*

[zule]

There are widespread theories about silicon based life http://nai.nasa.gov/astrobio/feat_questions/silicon_life.cfm

These hypotheses have too much incoherence despite the fact silicon has quite common characteristic with carbon.

 

So I find it difficult to imagine a life based on compounds as sulphur, arsenic or iron, much more different from the carbon.

 

Can you provide any information which this idea is based on?

[imposterzill]

Here's some things to consider:

 

Arsenic, which is chemically similar to phosphorus, while poisonous for most Earth life, is incorporated into the biochemistry of some organisms.[4] Some marine algae incorporate arsenic into complex organic molecules such as arsenosugars and arsenobetaines. Fungi and bacteria can produce volatile methylated arsenic compounds. Both arsenate reduction and arsenite oxidation have been observed in microbes.[5] Additionally, some prokaryotes can use arsenate as a terminal electron acceptor during anaerobic growth and some can utilize arsenite as an electron donor to generate energy.

Like carbon, phosphorus can form long chain molecules on its own, which would potentially allow it to form complex macromolecules if it were not so reactive. However, in combination with nitrogen, it can form much more stable covalent bonds and create a wide range of molecules, including rings.

 

 

Sulfur is also able to form long-chain molecules, but suffers from the same high reactivity problems that phosphorus and silanes do. The biological use of sulfur as an alternative to carbon is purely theoretical, but strains of sulfur-reducing bacteria have been discovered in exotic locations on earth, and also not so exotic locations, such as aging water systems.[6] These bacteria can utilize elemental sulfur instead of oxygen, reducing sulfur to hydrogen sulfide. Examples of this type of metabolism are green sulfur bacteria and purple sulfur bacteria. Examples of micro-organisms that metabolize elemental sulfur can be traced back 3.5 billion years on Earth.[7]

 

And as a different solvent(one) Hydrogen fluoride:

Hydrogen fluoride, like water, is a polar molecule, and due to its polarity it can dissolve many ionic compounds. Its melting point is -84 °C and its boiling point is 19.54 °C; the difference between the two is little more than 100 °C. HF also makes hydrogen bonds with its neighbor molecules as do water and ammonia. All of these things make HF a candidate to host life on other planets. However, HF suffers from the fact that it is an acid, with a pH similar to Sulfuric acid. See Hydrofluoric Acid.

 

Not much research has been done on liquid HF in regards to its ability to dissolve and react with non-polar molecules. It is possible that the biota in an HF ocean could use the fluorine as an electron acceptor to photosynthesize energy.

 

 

But my whole thing is if a planet is very hot, could a metal such as iron, working with various other sustances, and other chemical compounds that react in heat form structures sort of like how amino acids and such are on Earth. Or maybe they form other things that work like protiens. I don't know. But now here's something truly interesting to consider:

 

In 2007 V. N. Tsytovich and colleagues discovered the possibility of life-like behaviors being exhibited by dust particles suspended in a plasma, similar to conditions in interstellar space.[14][15] Computer models showed that when the dust became charged the particles could self-organize into microscopic helical structures capable of replicating themselves, interacting with other neighboring structures, and evolving into more stable forms. Similar forms of life were speculated on in Fred Hoyle's classic novel The Black Cloud.

[iNow]

Even though it's from wiki, you should really link to your source when you copy/paste like that. Cheers.

[imposterzill]

Sorry, but I'm still proposing that various substances react differntly in different temperature zones and not only that, could a completely exotic environment lead to stranger compounds that react with each other in ways unfathomable on Earth?

 

I was talking to someone on a science chatroom and someone tossed this idea. Iron based life could exist possible with a mercury sulphide metabolism. That's all they said. I'm just taking this into consideration.