Is ATP synthase found in all life?
Published: 4 February 2012 (GMT+10)
Shanna N., from the United States, wrote in response to ATP synthase: majestic molecular machine made by a mastermind:
But some anaerobic bacteria do not contain the enzyme ATP synthase, so it is not a requirement for life at all. They produce their ATP via glycolysis only, and use fermentation in place of cellular respiration. And thus it is perfectly understandable how simpler proteins in these primitive cells could have evolved into the complex molecular motor we know and love …
Brian Thomas, author of the article, responds:
Thanks for reading our article on the design of ATP synthase. Also, thanks for submitting your comment, which provides me the opportunity to clarify both the science and the semantics of my original article.
You wrote, “But some anaerobic bacteria do not contain the enzyme ATP synthase, so it is not a requirement for life at all. They produce their ATP via glycolysis only, and use fermentation in place of cellular respiration. And thus it is perfectly understandable how simpler proteins in these primitive cells could have evolved into the complex molecular motor we know and love…”
First, this wording appears to assume that my article asserted that ATP synthase is a requirement for all life. My wording did not go this far, but it could have! Here is the first line of my article: “Life depends on an incredible enzyme called ATP synthase, the world’s tiniest rotary motor.” I did not write, “All life depends … ,” but in fact all life does depend on ATPase. Here is why:
Obligate anaerobes may not use ATP synthase to manufacture ATP, but they do use it to pump protons out of their cytoplasm. They would die otherwise. All cells have ATP synthase, because all cells need it. As evidence, consider a 1986 technical paper in the Journal of Bacteriology, wherein the authors took electron micrographs of F1-ATPase in the anaerobic Clostridium bacteria.1
A recent paper by biochemist Douglas Axe put it this way: “Various forms of this ingenious device are found in all forms of life.”2
Thus, your statement, “But some anaerobic bacteria do not contain the enzyme ATP synthase” is apparently incorrect. If any bacterium is discovered without it, I would like to know about it.
In sum, all life depends on ATPase, but not all life depends on it for ATP production. Anaerobic bacteria use it to maintain pH balance instead. So ATPase must have been present in the very first cell. No known natural process could have built it up piece-by-piece, as you have suggested, because without the entire apparatus, there is no living cell and therefore no evolution, even in theory.
Since evolution by natural selection requires reproduction, and since reproduction requires life, which requires ATPase, the enzyme is therefore a prerequisite for evolution. But with evolution out of order until ATPase ‘appears’, evolution is not even in the running as a model to explain the origin of the molecular motor.
Incidentally, Axe also expressed the gist of my ATPase article by stating, “That is, there is no general principle of physics or chemistry by which ATP synthesis and proton fluxes have anything to do with each other. From an engineering perspective, however, it is often possible and desirable to design devices that force a relation upon otherwise unrelated processes. Of particular interest in this regard are devices like solar cells and turbines that harness energy from an available source in order to accomplish useful tasks that require energy. Life likewise crucially depends on many such devises, one of which provides highly efficient energetic coupling of the above two processes. This coupler, the proton-translocating ATP synthase, is a rotary engine built from eight or more protein types, some of which are used multiple times to form symmetric substructures.”2
Additionally, the necessity of engineering ATPase is actually just the tip of the iceberg. One amazingly revealing 2010 study in the journal Nature demonstrated how not only ATPase, but the entire electron transport chain apparatus and in fact whole mitochondria were absolutely essential to the ‘first’ eukaryote.
Of course, bacteria are not eukaryotes. But similar reasoning dictates that the whole microbial cell membrane—complete with stabilizing proteins and well-organized lipids—is required to keep separate the protons that ATPase pumps. This means that ATPase and the machines and information required to build it, as well as membranes and the machines and information required to build them, must stand together at once or they do not stand at all. Realistically building these kinds of interdependent apparatuses is only feasible in the context of a real engineer. Please consider a summary of the Nature article, published in ICR News: Study Demonstrates Complex Cells Could Not Evolve from Bacteria.
But another ‘red flag’ presents itself. You wrote, “And thus it is perfectly understandable how simpler proteins in these primitive cells could have evolved into the complex molecular motor we know and love…” Please permit me to reflect my understanding of your argument, then consider its supportability.
This seems to be what you are saying:
Premise 1: Some cells do not require ATPase to phosphorylate ADP, an essential process
for cellular life.
Premise 2: Such cells instead use simpler and more primitive proteins to phosphorylate ADP.
Conclusion: Thus, simpler proteins evolved into ATPase.
Assuming that I have not accidentally butchered your premises or conclusion, it is straightforward to show that this argument does not wash. First, the conclusion does not logically follow from the premises. If some cells do not use ATPase, and if those cells instead use other enzymes to phosphorylate ADP into ATP, then how would one logically distinguish between your conclusion that ATPase evolved, and the alternative idea that ATPase (as well as the “primitive” enzymes) was created?
The mere existence of both a motorized scooter and a sports car does not logically require that the former morphed into the latter. In fact, it is fully known that each was a separately intended creation from an intelligent and able (and real) engineer.
Another problem arises with Premise 2. What makes those critical glycolysis enzymes “simple” or “primitive?” Consider their structures, especially noting their precise three-dimensional shapes and hydrophobicity zones, their critically distributed electronegativities and assembly-line arrangement whereby the cell reaps no net ATP’s until ten specified enzymes all perform their appropriate duties. These are too complicated (i.e., the minimum system has too much specified complexity) for nature (physics and chemistry) to devise. This was described by Dr. Morton in this 1980 article: Glycolysis and Alcoholic Fermentation.
The enzymes required for fermentation are no more to be considered building blocks for ATP synthase than scooters can be considered building blocks for sports cars. Rather, in all these cases, the most straightforward origins inference is that the parts were arranged specifically according to exacting plans. And all known plans come from planners.
So no, it is not at all “perfectly understandable” how any proteins could have evolved into ATPase. This is because: 1. There is no example of this kind of molecular innovation occurring or having occurred in a lab (that is, it is not observed), 2. There is not even any realistic theoretical step-by-step mechanism that could invent any enzyme, let alone ATPase, and 3. Calculations and experiments show that innovating enzymes is not even possible3 (see also Searching for needles in a haystack).
I appreciate your considered and concisely worded feedback. I apologize for any ambiguity that my ATPase article’s wording may have caused. However, I believe that my original goal, to explain why ATPase must have originated from a super-intelligence, remains defensible and accurate.
Science Writer, Institute for Creation Research
- Mayer, F., Ivey, D.M. and Ljungdahl, L.G., Macromolecular organization of F1-ATPase isolated from Clostridium thermoaceticum as revealed by electron microscopy, Journal of Bacteriology 166(3):1128–1130, 1986. Return to text.
- Axe, D.D., The case against a Darwinian origin of protein folds, Bio-complexity 2010(1):1–12, 2010; bio-complexity.org/ojs/index.php/main/article/view/BIO-C.2010.1/BIO-C.2010.1. Return to text.
- Axe, D.D., Extreme functional sensitivity to conservative amino acid changes on enzyme exteriors, J. Mol. Biol. 301:585–595, 2000; citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.124.225&rep=rep1&type=pdf. Return to text.