E. coli that are young (blue) and old (red) have distinct properties.
STEWART/TIMMERMANN
There was hope for E. coli immortality because the bug lacked obvious asymmetries. Organisms that age tend to segregate damaged molecules preferentially into a compromised parent, and that segregation often shows up as a morphological asymmetry. Furthermore, the uncompromised offspring often turns up as a juvenile form that must undergo further development or growth before being competent for reproduction. Signs of such a progression were also lacking in the case of E. coli.
Stewart and colleagues undertook a more comprehensive examination of E. coli division dynamics, using a custom-made, computerized tracking system that followed E. coli...
