Endosymbiotic bacteria: GroEL buffers against deleterious mutations
Abstract
GroEL, a heat-shock protein that acts as a molecular chaperone, is overproduced in endosymbiotic but not in free-living bacteria, presumably to assist in the folding of conformationally damaged proteins. Here we show that the overproduction of GroEL in Escherichia coli masks the effects of harmful mutations that have accumulated during a simulated process of vertical transmission. This molecular mechanism, which may be an adaptation to the bacterium's intracellular lifestyle, is able to rescue lineages from a progressive fitness decline resulting from the fixation of deleterious mutations under strong genetic drift.
- Publication:
-
Nature
- Pub Date:
- May 2002
- DOI:
- 10.1038/417398a
- Bibcode:
- 2002Natur.417..398F