Microbial population growth is typically measured when cells can be directly observed, or when death is rare. However, neither of these conditions hold for the mammalian gut microbiota, and, therefore, standard approaches cannot accurately measure the growth dynamics of this community.

Researchers introduce a new method (distributed cell division counting, DCDC) that uses the accurate segregation at cell division of genetically encoded fluorescent particles to measure microbial growth rates.

Using DCDC, they can measure the growth rate of Escherichia coli for >10 consecutive generations. They also demonstrate experimentally and theoretically that DCDC is robust to error across a wide range of temperatures and conditions, including in the mammalian gut.

Furthermore, their experimental observations inform a mathematical model of the population dynamics of the gut microbiota.

DCDC can enable the study of microbial growth during infection, gut dysbiosis, antibiotic therapy or other situations relevant to human health.

http://www.nature.com/ncomms/2015/151130/ncomms10039/full/ncomms10039.html