Protons, the positively charged particles that help build every atom in our bodies, are starting to look less like classical billiard balls and more like quantum actors. A growing body of research now suggests that in living systems, these particles can tunnel, couple to spins and even behave as if they are part of a delicate quantum machine. The result is a provocative picture in which life’s chemistry may be shaped by the same rules that govern electrons in superconductors or photons in quantum computers.
Instead of treating quantum effects as rare curiosities, several teams are now arguing that they are woven into everyday biology, from how cells move energy to how DNA mutates. Their work does not claim that organisms are quantum computers, but it does show that protons in proteins, membranes and genetic material can follow quantum rules in ways that are measurable, controllable and potentially exploitable.
From classical hops to quantum rules
For decades, textbooks described proton motion in cells as a simple relay: a proton jumps from one water molecule to the next, or along a chain of chemical groups, in a largely classical way. That picture is now under pressure from experiments that track how protons move inside biological materials and find signatures that are hard to explain without quantum mechanics. In particular, a Study on lysozyme crystals reports that proton transfer is sensitive to the quantum property of electron spin, a dependence that points directly to quantum rules at work in a biological setting.
In that Study, researchers injected electrons into a protein environment and watched how protons responded, finding that the motion of the protons depended on whether the electrons had one spin orientation or the opposite. The team describes this as a “quantum secret” of proton motion, because the effect emerges from the quantum coupling between spins and nuclear motion rather than from any classical force, and they argue that it is the first time such behavior has been clearly seen in a biological system, as detailed in their Study.
Chiral phonons and the strange vibrations of life
To make sense of these results, I have to look beyond simple particle pictures and into the collective vibrations of matter. The same Study links the spin dependent proton motion to the excitation of chiral phonons, tiny vibrations in the crystal lattice that carry a handedness, or chirality. In a chiral phonon, atoms move in a circular pattern that distinguishes left from right, and this motion can couple to the spin of electrons, creating a bridge between mechanical vibrations and quantum spin states.
According to the researchers, these chiral phonons arise within the protein crystal and help channel energy in a way that depends on spin, which in turn shapes how protons move along hydrogen bonds and other pathways. The effect is described as remarkable because it shows that even the lattice vibrations inside a biological material can act as quantum objects, with their behavior captured in work published in the journal PNAS and summarized in analyses of chiral phonons.
Electron spin as a biological control knob
What makes this line of research especially striking is the suggestion that cells might use electron spin as a control knob for energy flow. In the lysozyme experiments, the team found that when electrons with one spin orientation were injected, proton motion along the protein was efficient, but when electrons with the opposite spin were used, proton movement was noticeably hindered. That contrast implies a direct link between electron spin and proton transport, hinting that spin states could regulate how energy and charge move through biomolecules.
Reporting on this work notes that the new results demonstrate how electron spin can affect the motion of protons in lysozyme crystals, suggesting a direct connection between quantum spin and the way energy is managed inside living systems. In other words, the spin of an electron, a purely quantum property, appears to influence a very practical biological task, the routing of protons, as described in coverage of how electron spin manages energy flow.
Rewriting the story of proton transfer in water and proteins
These findings also force a rethink of how protons move through water and along protein chains, processes that underpin everything from enzyme catalysis to cellular respiration. Until recently, the standard view was that proton transfer in aqueous environments occurred through a sequence of classical hops between water molecules, a mechanism often described as a simple relay. New work on proton motion in biological systems, however, argues that quantum effects, including tunneling and coherent coupling to electrons, play a significant role in how these transfers actually unfold.
One analysis of this research explains that proton transfer was long thought to be a matter of protons jumping from water molecule to water molecule, but that experiments now show a more complex picture in which protons and electrons interact in a coordinated way inside proteins and other biological structures. The same reporting highlights a schematic of protons and electrons in organisms on a magnetic substrate, underscoring how magnetic and quantum properties can shape proton motion, as outlined in discussions of how quantum physics guides proton motion.
Programming a “biological qubit” inside living cells
While these proton studies focus on naturally occurring processes, another frontier is opening in which researchers deliberately engineer quantum behavior into cells. A team at the University of Chicago reports that they have programmed cells to create what they call a “biological qubit,” a controllable quantum state embedded in living matter. Their argument starts from the premise that quantum mechanics is the foundation of everything, including biological molecules, and then pushes further by asking whether those quantum properties can be harnessed in a designed way inside cells.
In this first of its kind breakthrough, the researchers describe how they used genetic and molecular tools to make cellular components behave like elements of a quantum information system, with the goal of eventually integrating quantum control into biological circuits. One of the scientists emphasizes that quantum mechanics is the basis of all matter but that using it intentionally inside biology is the new direction here, a point captured in their account of how scientists program cells to create a biological qubit.
Coordinated energy transfer and the promise for technology
The same spin sensitive proton motion that fascinates physicists also carries clear technological implications. In the lysozyme work, the researchers show that when electrons with the opposite spin were injected into the protein, proton movement was noticeably hindered, which means that simply flipping spin can modulate how efficiently energy is transferred along a molecular pathway. That kind of control suggests that biological materials could be tuned to act as spin filters or quantum controlled conductors, with potential uses in sensors or nanoscale devices.
The team behind these experiments argues that understanding how tiny particles coordinate energy transfer inside cells could inform advances in medicine, energy and nanotechnology, since the same principles that guide proton motion in proteins might be adapted to synthetic systems. Their report notes explicitly that when electrons with the opposite spin were injected, proton movement was noticeably hindered, and that this effect is linked to broader applications in medicine, energy and nanotechnology, as described in work on how tiny particles coordinate energy transfer inside cells.
Quantum tunneling and the fragility of DNA
Quantum behavior in biology is not always beneficial. One of the clearest examples of its darker side comes from DNA, where quantum tunneling can destabilize the genetic code. In quantum tunneling, a particle such as a proton passes through an energy barrier that it could not overcome classically, appearing on the other side without ever having enough energy to climb over. In the context of DNA, this means a proton can shift between different positions in a base pair, potentially changing how the bases pair up and leading to mutations.
Analyses of this phenomenon describe how the freaky physics of quantum tunneling may mutate genes by allowing a proton in DNA to move in such a way that a base pairs incorrectly, for example causing a base to pair with adenine rather than guanine. The reporting emphasizes that this tunneling makes DNA strands more unstable, highlighting how quantum effects can threaten genetic stability, as detailed in discussions of how quantum tunneling makes DNA more unstable.
From speculation to detailed models of DNA tunneling
The idea that quantum tunneling could drive random DNA mutations has a long history, but for years it was treated as a speculative side note rather than a central mechanism. Recent work has revisited that proposal with more sophisticated models and simulations, arguing that tunneling events may be more common and more consequential than earlier estimates suggested. These studies focus on how protons in hydrogen bonds within DNA base pairs can tunnel between positions, creating so called tautomeric forms that mispair during replication.
One report notes that the idea that this could happen in DNA mutation was first suggested decades ago, but that the mechanism was largely overlooked until new calculations and experiments revived it. The same coverage explains that the latest work, published in Nature Communications Physics, supports the view that quantum tunneling could drive random DNA mutations, reinforcing the case that quantum behavior is not a rare curiosity but a routine part of genetic chemistry, as summarized in analyses of how quantum tunneling could drive random DNA mutations.
Proton leaks, mitochondria and the limits of classical flow
Beyond DNA and proteins, protons also define how cells generate and dissipate energy, especially inside mitochondria, the organelles that produce adenosine triphosphate. A key part of this machinery is the mitochondrial proton leak, the process by which protons cross the inner membrane without driving ATP synthesis, effectively wasting some of the energy stored in the proton gradient. Traditionally, this leak has been modeled as a classical flow of protons through channels or defects, but newer mathematical work suggests that a more nuanced description is needed.
In a detailed mathematical modeling of the mitochondrial proton leak, researchers start from an Introduction that frames the mitochondrion as a vital cellular organelle that produces energy in the form of adenosine triphosphate and then explore how proton movement deviates from a simple classical flow. Their abstract notes that the model goes beyond the classical flow of protons, implying that additional mechanisms, potentially including quantum effects, may be required to fully capture how protons leak across the membrane, as laid out in the mathematical modeling of the mitochondrial proton leak.
Open quantum systems and a new view of genetic stability
To connect all these threads, some theorists are turning to the framework of open quantum systems, which treats quantum objects that interact continuously with their environment. DNA inside a cell is not an isolated molecule in a vacuum, it is bathed in water, buffeted by thermal noise and surrounded by proteins, all of which can disrupt or shape quantum behavior. An open quantum systems approach to proton tunnelling in DNA tries to capture this messy reality by modeling how environmental interactions influence tunneling rates and the resulting mutations.
The abstract of one such study states that one of the most important topics in molecular biology is the genetic stability of DNA and identifies proton tunnelling as a threat to this stability. The authors argue that an open quantum systems treatment shows that tunnelling may play a larger role in mutation than has hitherto been suggested, reinforcing the idea that quantum effects are not washed out by the warm, wet cellular environment but instead persist in ways that matter for evolution, as described in the open quantum systems approach to proton tunnelling in DNA.
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