3 ms·
Here's the actual article: http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001926 http://www.plosbiology.org/article/info:doi/10.1371/journal
by ascotan 12y ago
Here's the actual article: http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001926 http://www.plosbiology.org/article/info:doi/10.1371/journal....
tl;dr
The hypothesis here is that early bacteria/archea basically worked a lot like a car battery, with a + and a - terminal and the the permeability of the cell membrane allowed H+ to flow through the cell turning the little ATPase crank to turn out ATP. The unspoken hypothesis here is that organisms like this probably lived on the rock surface of a geothermal vent when there aqueous phase was acidic and there was another 'layer' that was alkaline (probably on the rock face?).
Overtime a Na+/H+ exchanger was added to increase the movement of H+ across the membrane which made the ATPase crank turn 60% faster. Eventually in phase 3 ion pumps really supercharged the ion gradient and allowed these organisms to move into environments that didn't need a bi-phasic H+/OH- layer. It's likely that the ion pumps and non-permeable membranes formed as the little guys moved out of the geothermal vents and diverged into new environments, giving rise to the divergent archea and bacteria.
- doctoboggan 12y agoThe article specifies where they think the organism lived. > Data from the study strongly suggest that LUCA lived in the area where ancient seawater, dense with positively charged particles called protons, mixed with warm alkaline vent fluid, which contained few protons. The difference in the concentration of protons across these two environments enabled protons to flow into the cell, driving the production of a molecule called adenosine triphosphate (ATP) which powered the growth of cells, just as it does today.
- deleted 12y ago[deleted]
- ErikRogneby 12y agoGreat summary. I appreciate the automotive metaphors.
- twic 12y agoThey're not metaphors - the ATPase actually does spin round to make ATP: http://biocadmin.otago.ac.nz/pic/ATPaseanim.gif http://biocadmin.otago.ac.nz/pic/ATPaseanim.gif Although it's more like a turbine than a crank. And if you're increasing the degree of a gradient of charged particles above what happens naturally, you're supercharging it!
- ErikRogneby 12y agoEven more awesome then.