Why Purple Bacteria Always Have Big Rings ⚡ экспресс
The LH2 light-harvesting complexes in purple bacteria are molecular rings with usually 8 or 9 repeating segments. So why don't we ever see a 7-fold symmetry? Using a closed quantum optical model of coupled dipoles, researchers showed that this geometry makes energy transfer inefficient. It's a glimpse into how evolution rejects flawed designs right at the molecular scale.
In the depths of murky ponds, purple bacteria lurk. Their secret to surviving in near-total darkness is rings of light-catching molecules, arranged like a round dance: each dancer passes energy to a neighbor. But if the round dance has fewer than seven participants, the dance breaks down—energy scatters, and disorder takes over. Over billions of years, nature set a minimum: the ring always has 8 or 9 links, never fewer than seven.
Using spectroscopy (analysis of light absorption) and photometry (brightness measurement), scientists confirmed that small rings suffer heavy losses. In large rings, energy flows instantly and almost without heating. The secret lies at the quantum level: excitation envelops the entire ring as a single wave—like water frozen in a perfectly smooth circular channel, wasting no energy on eddies.
These living solar cells are already inspiring engineers. Tomorrow’s solar panels might copy this bacterial design—and capture even dim twilight.
🎯 Purple bacteria absorb infrared light—invisible to us, but felt as warmth. They thrive on this meager glow where other organisms starve.