In a groundbreaking advancement at the intersection of quantum physics and biological chemistry, a team of researchers from the Hebrew University of Jerusalem, in collaboration with experts from the Weizmann Institute of Science and Ben Gurion University, has unveiled a phenomenon that reshapes our understanding of proton transport within biological systems. Traditionally seen as a purely chemical process driven by proton hopping among water molecules and amino acids, proton transfer is now shown to be intimately tied to the quantum property of electron spin when occurring in chiral biological environments such as proteins. This astonishing revelation opens new vistas in our grasp of energy and information flow in living organisms, suggesting more intricately controlled and selective mechanisms than previously imagined.
At the heart of this discovery lies lysozyme, an enzyme prevalent across many living entities, whose crystalline form provided the perfect model system to investigate the nuances of proton movement intertwined with electron spin. Using sophisticated experimental setups, the team injected spin-polarized electrons into lysozyme crystals and observed a striking modulation in proton conductivity depending on the electron spin orientation. Electrons possessing one spin facilitated proton movement, while the opposite spin configuration significantly impeded it. This phenomenon underscores a spin-dependent coupling mechanism, challenging the classical perception of proton transport as merely a diffusive chemical event.
The quantum underpinning of this behavior is deeply rooted in the Chiral Induced Spin Selectivity (CISS) effect, a principle describing how chiral molecules preferentially interact with electrons of specific spin orientations. Here, the chirality of biological crystals orchestrates the interaction between electron spin and proton dynamics via the excitation of chiral phonons—quantized lattice vibrations that act as mediators. These phonons essentially couple electron spin states to the vibrational modes of the molecular lattice, enabling a quantum dialogue that modulates proton mobility in a spin-selective manner.
This breakthrough reveals a quantum aspect of bioenergetics that was largely unappreciated until now. Protons, fundamental carriers of energy within cells and central players in processes like ATP synthesis and cellular respiration, do not navigate their biological pathways alone. Instead, their journey intertwines with electron spin states, enabling a nuanced regulation that could imbue living systems with enhanced efficiency and selectivity in energy transduction. The ramifications of these findings extend beyond fundamental science, hinting at revolutionary applications in designing biomimetic devices and quantum-informed technologies.
According to Dr. Naama Goren from the Hebrew University’s Department of Applied Physics and Nano Center, these insights transform our understanding of proton transport by revealing its quantum mechanical dimension rooted in the molecular chirality of biological crystals. The study’s revelations imply that energy and information transfer within living systems is not only a chemical phenomenon but also a manifestation of quantum physics, creating a new paradigm for interpreting biological function and complexity.
Prof. Yossi Paltiel, also from the Hebrew University, emphasizes that this newfound electron spin-proton coupling mechanism presents exciting prospects for developing technologies capable of emulating or controlling biological information transfer. The precise manipulation of proton flow via electron spin states could herald a new generation of bio-inspired quantum devices, potentially revolutionizing fields such as molecular electronics, information processing, and nanomedicine.
The team’s methodology involved delicate experimental studies where spin-polarized electrons were introduced into lysozyme crystals, and proton mobility was monitored using advanced spectroscopic and microscopic techniques. These observations revealed that the spin orientation of electrons directly influences the lattice vibrations—chiral phonons—that facilitate proton hopping. The synergy between these vibrational modes and electron spin states forms the basis for a controllable, spin-dependent proton transport mechanism dictated by the inherent chirality of the biological crystal matrix.
This coupling not only enforces a directional preference for electron spins in proton transfer but also provides evidence that quantum mechanical properties can be harnessed within biological materials at ambient conditions. The realization that quantum spin effects impact proton dynamics in biological molecules bridges a long-standing gap between quantum physics and biochemistry, inviting a re-examination of many biological processes through a quantum lens.
Furthermore, these findings illuminate potential pathways to explain the remarkable efficiency observed in biological energy conversion systems. If electron spin states can modulate proton flux, living organisms may exploit such quantum mechanisms to fine-tune metabolic reactions and optimize energy flow at the molecular level. This quantum choreography of spins and protons may underpin key biological phenomena ranging from enzymatic catalysis to signal transduction.
Beyond their immediate biological implications, the researchers speculate that leveraging this spin-proton interplay could inspire novel quantum devices capable of interfacing with biological systems or even controlling enzymatic activity through tailored spin injections. Such devices could pave the way for radical advances in bioelectronics, spintronics, and quantum information technologies, pushing the boundaries of what can be achieved by merging quantum mechanics with life sciences.
The publication of these findings in the prestigious Proceedings of the National Academy of Sciences marks a seminal moment in contemporary science, as the experimental validation of electron spin’s influence on proton transfer in chiral biological crystals firmly establishes quantum biology as a vibrant field of inquiry. This work not only deepens our comprehension of life’s molecular machinery but also sets the stage for innovations that harness quantum phenomena for technological breakthroughs.
As the scientific community digests these revelations, the implications ripple across multiple disciplines. From the design of new pharmaceuticals targeting proton-coupled electron transport pathways to the development of sustainable energy solutions inspired by nature’s quantum exploits, this research unveils a fundamental layer of biological complexity previously hidden from view. The nuanced control of proton transfer mediated by spin-selective interactions invites a redefinition of biological function, from static chemistry to dynamic quantum engineering.
With this pioneering research, the Hebrew University-led team paints a picture of life as an elegant quantum dance, where protons and electrons coalesce through the choreography of chirality and spin. This elegantly orchestrated interaction highlights the sophistication of biological systems and opens transformative avenues for science and technology, underscoring the profound unity of physics and life.
Subject of Research: Not applicable
Article Title: Coupling between electrons’ spin and proton transfer in chiral biological crystals
News Publication Date: 5-May-2025
Web References: DOI link
References: Proceedings of the National Academy of Sciences
Image Credits: Dr. Shira Yochelis and Naama Goren at the HUJI Nano center
Keywords
Protons, Electron spin, Quantum chemistry, Chirality, Crystals
