Living solar panels ...

[Duda Jarek]

Biology has to offer many kinds of energy conversions - for example solar into ATP and later glucose. We can now take whole organisms and eg burn them to gain energy (biofuels).

But remember where natural gases (and other fossil fuels) are from...

Biology knows these metabolism pathway!

Maybe we could take for example unicellular photosynthesizing organism and put into it genes of required proteins?

Just to make it work, than take a few dozens(hundreds) of generations of artificial selection to create cheap, efficient(?) living solar panels, from which we could just pump eg. methane...

 

About different kind of energies ... remember that in microscopic scale chemical reactions are reversible - the dominant direction depends of parameters (like ATPase H+).

We know that we have mechanisms to produce heat using ATP. Now imagine that it has changed parameters to need more ATP density than there is in around - above some temperature, it should work in opposite direction - change ADP->ATP using heat!

We have plenty of microbes kilometer below... what do they eat? Chemical energy of minerals? They should be about their minimum...

Maybe they can feed with geothermal energy?

To check it we should check if water with eg pyrolobus furmanii cool down faster than it should. If yes, a bit of artificial selection and maybe we could produce natural gas from surpluses of thermal energy in a factory.

 

Another type of energy is vibration. Myosin can change ATP into movement. Again - with changed parameters, it should be able to work in opposite direction - if it would be attached to cytoskeleton, it should produce energy from vibrations.

What for? For example to actively absorb them. For example to reduce turbulations in water... we should search for them in fishes, water mammals.

Thanks of this we could produce active sound/vibration dampers, which produce energy...

Edited August 8, 2008 by Duda Jarek

[Duda Jarek]

About vibration absorption ... myosin was only example - it's functions are too directed, too complicated to be reversed in practice.

But imagine a protein which is connected to cytoskeleton (for example on crossings of filaments) and catches ADP and phosphate. Now if the cell vibrates, movement of the cytoskeleton is transferred to the protein which can enforce binding the molecules into ATP.

I'm not saying that it's simple, but it looks to be possible.

And if yes, mother nature is extremely inventiveness creature

Look how sophisticated machinery was constructed to use energy from light...

 

About using heat - I agree that it looks even less probable...

At the first spot it seems to be against classical thermodynamics - converting pure heat into different energy. But this theory is strong simplification. For example hot iron emits photon. Heat energy is random microscopic movement - a noise. The trick is to use a resonance to gather surrounding frequencies and convert them into coherent movement - light, sound ... Lately it was proved that it can be done - change heat into sound and then we can use for example piezoelectric effect to convert it into electricity:

http://unews.utah.edu/p/?r=111907-2

The question is if it can be done in microscopic level using proteins and temperatures smaller than 120C? For example a molecule which can resonance to bind ADP and phosphate.

If yes - evolution should have found it...

 

We have plenty of microbes in deep earth for billions of earth - there were/are some sources of chemical energy, but generally they are starving. Scientist has problem to explain their extremely low metabolism:

http://www.sciencemag.org/cgi/content/full/sci;276/5313/703

Extremely low metabolism has also psychrophiles - but it's because of cold - all reactions are slowed down. It's not because of lack of energy - they usually have access to it.

We are talking about thermophiles , which should have consumed most of available chemical energy sources for last billions of years and new come extremely rarely.

Remember that energy is needed not only for metabolism, reproduction ... it's necessary to sustain the structure of the organism, fight with increasing entropy - especially in high temperatures!

Their life would be much easier if they would be able to feed not only with chemical energy, especially when there is plenty of it in heat and tectonic vibrations around...

[Duda Jarek]

They could also feed with heat in indirect way : hot objects emit thermal infrared (a few micrometers)...

We even want to use it in much smaller temperatures for example to power MP3 players:

http://www.sciencemag.org/cgi/reprint/320/5883/1585.pdf

 

Maybe some of thermophiles have constructed photosynthesis for these frequencies... ?

[Duda Jarek]

I was thinking about 2nd law of thermodynamics and crystallization.

During this process we get higher ordering (lower entropy), but the cost is energy difference between free and bind molecule - this energy is usually just dispersed around, increasing general temperature.

But what if we wouldn't allow this energy to run away randomly ... for example storing it in chemical energy of some molecule, like ATP ...

 

That lead me to mechanisms that could allow organisms to feed directly with heat (not using thermal infrared):

 

Let say that we have two molecules(A,B) which has larger total energy separated(E1) than when they are bind (E2<E1).

Additionally there is energy barrier between these states.

Now when they are bind in solution, their thermal energy statistically sometimes exceed the barrier, and they split (reducing temperature!).

But to bind them back, they not only have to reach the barrier, but they have also to find each other in the solution - it's not very likely, so statistically concentration of AB is relatively small comparing to concentration of separated molecules.

 

Now we will need a catalyst which reduce the barrier, but then use the energy difference for example to bind ADP and phosphate.

For example it catches all required molecules and uses energy stored in own structure to take A and B closer, to make them reach the top of the barrier, then use energy they produce to bind ADP + P and restore own energy.

 

I know - this enzyme would work in both directions, but concentration of AB should be small, such that the wanted direction should dominate.

Is here any problem?