A cell builds proteins the way a translator builds a sentence out of words. If the translator is tired or has lost a tool, mistakes creep in, and the meaning falls apart. Inside the cell, accuracy is the job of transfer RNA, the molecule that carries amino acids to the site where proteins are assembled. It bears a rare chemical tag called manQ, which helps keep the 'words' from getting mixed up. With age, this tag disappears.
Queuine is a compound that human cells cannot make on their own. It is supplied only by gut bacteria. When those bacteria dwindle or their composition shifts, queuine runs short, and transfer RNA loses its tag. As a result, proteins get assembled with errors, and the cell ages faster. The researchers added queuine to the food of flies and mice: the accuracy of protein assembly was restored, and the animals lived longer and stayed healthier.
This means aging is not just wear and tear, but a process that can be partly controlled. Give the cell back the compound it lacks, and its 'translator' starts working accurately again. So far the experiments have been done only in animals, but in the future there may be diets or probiotics that help people maintain their queuine levels. That makes gut bacteria not just neighbors, but important allies in the fight against aging.
Queuine was discovered in the 1970s, but its role in aging has only now been figured out. It is named after the letter Q, which stands for its precursor in the genetic code.
Not published on arXiv. Here are its page, the PDF and the formalization: you can check it yourself, not only read our account.