Aternate life chemistry

[Moontanman]

In recent years the discovery of the Bucky ball, C60 molecule, was touted as proof of the versatile nature of the Carbon bond and an example of why it was so good at being the scaffolding of life. But another element can make Bucky ball type molecules, Boron. The B80 molecule is stable and shows that Boron is also a very versatile atom, does this point to the possibility that Boron might in some environments make a suitable scaffolding for life as well?

[insane_alien]

not really, just because boron can form a buckyball like structure doesn't mean it is versatile enough to replace carbon in biochemistry. for instance, it does not form long chains like carbon which are pretty much essential for fats, proteins and other chemicals. carbon forms the base of millions more compounds than any other element.

[Moontanman]

Actually Boron does form complex molecules in the same vein as Carbon. At somewhat different pressures and temperatures Boron can imitate carbon in several areas. The point is that while Silicon has been thought a viable alternative to Carbon in very cold temps like the surface of Titan or as Silicone at temps like the surface of Venus Boron can also form complex chains of molecules but Silicon cannot form Bucky balls, Carbon can and Boron can.

 

http://www.daviddarling.info/encyclopedia/B/boron-based_life.html

[Moontanman]

Alternative life chemistries other than boron life can be discussed here as well. Is anyone interested in possible alternatives to life as we know it?

[pioneer]

The picture below is not an alternate atom for life but is a representation of a configuration a bunch of water molecule can make or (H2O)280. It is held together with hydrogen bonding, making it very flexible in terms of shifting between two versions.

 

 

If we look at C, what makes it very useful for life is it can form four covalent bonds allowing long chains and a wide variety of shapes such as the Bucky Ball. If you look at water or H2O, it can sort of simulate this with hydrogen bonding. This allows the formation of a water matrix that has four bonds, with the Hydrogen bonds sort of playing an analogous role of the four covalent bonds of carbon. This allows water to make similar things but in a way that is easier to shift between shapes. You can make a water Bucky Ball and it can shift into something else. One can also make even more complex shapes, like (H2O) 280 , which can shift between configurations or clean the slate. Moving between these various shapes means the formation and breaking of a lot of weak bonds allowing a significant energy and entropy change. Water routinely uses this to make and break the -OH covalent bond to get the pH affect.

[Moontanman]

The picture below is not an alternate atom for life but is a representation of a configuration a bunch of water molecule can make or (H2O)280. It is held together with hydrogen bonding, making it very flexible in terms of shifting between two versions.

 

 

If we look at C, what makes it very useful for life is it can form four covalent bonds allowing long chains and a wide variety of shapes such as the Bucky Ball. If you look at water or H2O, it can sort of simulate this with hydrogen bonding. This allows the formation of a water matrix that has four bonds, with the Hydrogen bonds sort of playing an analogous role of the four covalent bonds of carbon. This allows water to make similar things but in a way that is easier to shift between shapes. You can make a water Bucky Ball and it can shift into something else. One can also make even more complex shapes, like (H2O) 280 , which can shift between configurations or clean the slate. Moving between these various shapes means the formation and breaking of a lot of weak bonds allowing a significant energy and entropy change. Water routinely uses this to make and break the -OH covalent bond to get the pH affect.

 

Are these water balls stable structures? Bucky balls are as stable as other carbon or boron molecules and can be used to store smaller atoms inside the Bucky ball like a small cage.

[insane_alien]

no, pioneer is talking out his ass again, he thinks hydrogen bonding is the be all and end all of life. he generally ignores reality in order to sustain his viewpoint.

[pioneer]

I am not discounting what we know. I am trying to add another layer to the analysis. You shouldn't be so defensive, since it shows you are not looking at life logically. Adding the global variables water and hydrogen bonding is not going to be easy. But I get the impression we are trying to avoid reality for reasons other than logic.

 

Let us do it this way. Let us take a cell and remove all the H-bonding. We still will have all types of long carbon based molecules such as DNA but no way to form template relationships. The enzymes will never form the correct shapes and life won't work. According to you this is not important.

 

Let us take a cell and leave the hydrogen bonding within all the macromolecules of life, but take away the water. The shapes will still form but we now lack the surface affects. According to you this is also not important. I am not blaming you for this but your empirical education. This allows us to leave out variables and still get reasonable results.

[iNow]

IBut I get the impression we are trying to avoid reality for reasons other than logic.

Mr. Pot, please come over here and meet Mr. Kettle.

[pioneer]

I am using logic and basic observational data. I admit my knowledge of the details is not that good. But this is a new branch of science and needs to start at the basics. I am not trying to develop the science for only one narrow observation. The goal is a global model that needs to be consistent with the big picture, first. Every time I try to build, you piss on the seedling trying to kill it before it grows. I have to keep digging the same soil to remove the affects of pests. If you can't see the basic logic you will never see the more advanced stuff. Maybe you can give me logical reasons for your opinion. Maybe I am missing something and if I am, I am willing put it to rest.

[Moontanman]

I'm not sure why hydrogen bonding is important in this discussion. No matter what fluid or bases life forms in or adapts to I am quite sure hydrogen will be a big part of life. I think it is safe to say that life will always depend on hydrogen in some form. Saying that life might use some fluid other than water or a structure based on something other than carbon doesn't mean hydrogen wouldn't be an important part of life. I think it would be safe to say that hydrogen is a basic part of all life. I am not questioning the importance of hydrogen I am questioning the assumption that all life will be like ours based on carbon, water, and DNA.

[pioneer]

Life as we know it requires C, which can form 4 bonds. It also requires a medium, water. Alternate life might need a variation on this theme. Si is often chosen because it is below C on the periodic table and can also form 4 stable covalent bonds. Other atoms can be made to form 4 bonds, such as NH4, but N doesn't form long chains. Boron is trivalent or will form three covalent bonds, which although can still form extended structures has a limitation relative to C or Si. The chemistry gets too complicated.

 

Using current life, as a model, we know silicones are stable and don't break down easily with enzymes based on C. This means the enzymes needed for Si will need to be more aggressive. But the paradox created is Silicone polymers are more stable than C analogs such that Si polymers needed for silicone enzymes begin with less built in energy. We might still be able to compensate for this with higher temperature environments or a more aggressive continuous phase.

 

Now we need an energy source to run the life machine. Life on earth uses CO2 and its continuous phase solvent phase H2O, as the feed stock for photosynthesis. The CO2 is a gas at room temperature. The Si equivalent is SiO2 which will form a solid at room temperature as sand and glass. The question is what solvent do we need that can play the role of continuous phase, also be part of photosynthesis or some other means of food generation and dissolve rocks? This place a limit on solvents since glassware is not affected by most solvents. One simple exception is HF. Maybe that is part of our solvent package so we can make SiO2 based food out of rocks. Again we may be stuck using water as part of an acid medium. But runs into surface tension problems.

 

Maybe we need another energy source and can't use photosynthesis. Maybe we need to begin with silicone hydrides. But this is not likely if there is too much oxygen competing for H and Si. But without O you don't get big polymers. Also if we get rid of the O what becomes the terminal electron acceptor? Maybe F can do it all, but F is not conducive to polymers if we leave out the O.

Edited September 30, 2008 by pioneer

[Moontanman]

Life as we know it requires C, which can form 4 bonds. It also requires a medium, water. Alternate life might need a variation on this theme. Si is often chosen because it is below C on the periodic table and can also form 4 stable covalent bonds. Other atoms can be made to form 4 bonds, such as NH4, but N doesn't form long chains. Boron is trivalent or will form three covalent bonds, which although can still form extended structures has a limitation relative to C or Si. The chemistry gets too complicated.

 

Using current life, as a model, we know silicones are stable and don't break down easily with enzymes based on C. This means the enzymes needed for Si will need to be more aggressive. But the paradox created is Silicone polymers are more stable than C analogs such that Si polymers needed for silicone enzymes begin with less built in energy. We might still be able to compensate for this with higher temperature environments or a more aggressive continuous phase.

 

Now we need an energy source to run the life machine. Life on earth uses CO2 and its continuous phase solvent phase H2O, as the feed stock for photosynthesis. The CO2 is a gas at room temperature. The Si equivalent is SiO2 which will form a solid at room temperature as sand and glass. The question is what solvent do we need that can play the role of continuous phase, also be part of photosynthesis or some other means of food generation and dissolve rocks? This place a limit on solvents since glassware is not affected by most solvents. One simple exception is HF. Maybe that is part of our solvent package so we can make SiO2 based food out of rocks. Again we may be stuck using water as part of an acid medium. But runs into surface tension problems.

 

Maybe we need another energy source and can't use photosynthesis. Maybe we need to begin with silicone hydrides. But this is not likely if there is too much oxygen competing for H and Si. But without O you don't get big polymers. Also if we get rid of the O what becomes the terminal electron acceptor? Maybe F can do it all, but F is not conducive to polymers if we leave out the O.

 

At very cold temps, around the temps we find on Titan Si could form chains and rings like carbon without the help of oxygen. Such molecules could also sport methane radicals attached to the Si chains. This would allow even more complex molecules to form that would still be unstable enough at these low temps to react in the way hydrocarbons do on Earth. It also just so happens that liquid hydrocarbons are pretty good at dissolving these Si chains. Since water would be rock at these temps it would be able to react with these Si chains and they would be stable. Just another possibility. Lots of hydrogen, Si and C sloping around there, anything could happen!