A type of Streptomyces bacterium that lives in soil forms multicellular structures in which some bacterial cells have specialised roles, like the cells of complex organisms – and a computer model suggests how this phenomenon evolved
A colony of Streptomyces coelicolor bacteria
WIM VAN EGMOND/SCIENCE PHOTO LIBRARY
In the multicellular soil bacterium Streptomyces coelicolor, some cells start producing lots of antibiotics after mutations delete big chunks of their genomes. Now a computer model has helped to confirm that this is no accident but an evolved mechanism for dividing labour among cells in a colony.
“With Streptomyces, permanent differentiation happens by breaking the genome,” says Enrico Sandro Colizzi at the University of Cambridge.
While definitions vary on what makes an organism multicellular, for many biologists it isn’t simply about having lots of cells, …