Magnetic Bacterium Extends Roundworm Lifespan by Suppressing Cell Death

A magnetotactic bacterium, a microbe best known for producing microscopic magnetic structures, extended the average lifespan of roundworms by 43.39% in a new study, apparently by suppressing a form of cell death linked to aging. The findings were published in the journal Free Radical Biology and Medicine by researchers led by Prof. An Xu at the Hefei Institutes of Physical Science, part of the Chinese Academy of Sciences.

In experiments with the roundworm Caenorhabditis elegans, a common aging model, worms treated with the bacterium Magnetospirillum magneticum AMB-1 lived an average of 43.39% longer than untreated worms, while older treated worms also showed improved neurological function and better-preserved intestinal integrity.

Magnetotactic bacteria produce intracellular structures called magnetosomes, which contain magnetic minerals and help the microbes orient themselves along magnetic fields. Their biocompatibility has already drawn interest for drug delivery, imaging and cancer-related applications, though their effect on aging had received little attention before this study.

The researchers traced AMB-1's effect to suppression of ferroptosis, a form of cell death driven by iron buildup and damaging lipid oxidation. Wild-type AMB-1, which produces magnetosomes, extended lifespan more than a strain that could not produce them, and a fully non-magnetotactic strain did not extend lifespan at all. AMB-1 lowered iron accumulation and lipid peroxidation in the worms, and genetic experiments linked the effect to the genes ftn-1, bli-3 and ads-1.