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This is a thread on how the moon made mitochondria. So some billions of years ago (4-5billion) a Mars like body called Theia collided with proto Earth.
The collision drove the iron core of Theia deep into Earth’s crust, whilst it’s surface accreted with Earths mantle. The impact superheated Earth to above 1500 degrees and made it molten. The moon catapaulted off (and possible was at least two moons that later smashed
Into each other, hence why moon thicker on one side.). Anyway everything molten, and lighter elements like silicon rose more superficially, iron sank deeper. If you ever wondered why there is a truckload of silicon on beaches, and not iron sand, like me.
Other thing about superheating is the carbonisation of material to produce a heavy CO2 atmosphere. Interestingly, now we have lots of iron hanging around beneath liquid seas, Fe(II) is very happy to react with H2O to release hydrogen.
This is serpentinisation (don’t ask why). Now. So when we think about modern life forms, there is something called the continuity principle, where ancient chemistry is probably preserved to some degree in biochemistry because rules about energy conservation and thermodynamics.
Anyway so when we consider what the earliest chemistry was, we should be able to find it in the earliest biochemistry. Which we do. So because we have a ton of CO2 and H2 hanging around sea vents where hot rock meets seawater
We get bacteria that are anaerobic because oxygen isn’t really available yet. Their metabolisms are exclusively H2 and CO2 dependent. How? They use the acetyl CoA pathway. YOU GUYS KNOW THAT ONE!!
And even better when scientists have investigated LUCA (my new fave thing), the Last Universal Common Ancestor, the thing that became bacteria, eukaryotes and archaea, it’s metabolism also hinged on those kind of pathways.
Basically genomics and some chemistry and spontaneous organic and inorganic chemistry, comes up with the idea that organism was salty with a lipid bilayer. It extruded salt and kept potassium. (Sea vents are high in potassium).
Probably had DNA rings with RNA transcripts. And before LUCA, enzymes and pathways were slow to emerge. Enzymes are proteins. Proteins are complicated and don’t magically assemble all too easily. Instead early chemistry probably included rare carbon-metal molecules.
That acted as catalysts. But also, every time you do the genomics and the maths and evaluate minerals and chemistry in sea vents. The important catalysts that don’t require proteins or DNA to assemble: are thio esters and iron sulphur groups.
So these groups are actually still preserved in most enzymes - the active site and catalyst contain such carbon metal bonds. The protein enzyme just holds things in the right conformation.
The reason these kind of molecules are important is because they’re promiscuous with their electrons. But you’ll still be very familiar because they’re in basically all cool things
Like chlorophyll. That gout enzyme xanthine oxidase. Heme synthesis. The electron transport chain.
For any physicists the usefulness of this esters and ferroredoxins etc, is that they somehow manage to choreograph electrons for redox reactions in a way that conserves energy (third method of energy conservation minimal using free energy loss)
By having multiple redox sites they can couple exergonic and endergonic reactions in the same moment and not need energy input. Flavins and quinones (things in the electron transport chain) are therefore based on these.
They don’t need ATP. They can make ATP. Thioesters seemed to be the energy currency before ATP, with even higher energy from bond hydrolysis. Acetyl CoA is actually a thioester itself. You can mock up Acetyl CoA like cycles with just metals and CO2 so it’s pretty primitive.
Additionally a lot of sea vents are very alkaline and eject into acid sea water (which used to be very acidic from high CO2) generating an automatic proton gradient that can be used to drive Other chemical reactions. Little lab based versions can even power lights!
I mean it’s not like mitochondria use hydrogen ions to make energy or anything 
Anyway also some crazy weird things at sea vents now including these worms with red plumes made with haemoglobin but they use it to trap hydrogen sulphide they feed to their captive bacteria who then give them carbon compounds in return.
Creatures round there also make armour out of iron compounds to defend from venomous snails. So it’s a bit exotic. So there you go. The moon and mitochondria.
