Data from: Use of a microfluidic platform to uncover basic features of energy and environmental stress responses in individual cells of Bacillus subtilis

Bacteria use a variety of stress-sensing systems to sense and respond to
diverse stressors and to ensure their survival under adverse conditions.
The gram-positive bacterium Bacillus subtilis responds to energy stress
(ATP depletion) and to environmental stressors using two distinct
stress-sensing pathways that converge on the alternative sigma factor σB
to provoke a general stress response. Past efforts to study the σB stress
response in bulk culture and on agarose pads were unable to visualize the
responses of individual cells under tightly controlled conditions for
extended periods of time. Here we use a microfluidics-based strategy to
discern the basic features of σB activation in single cells in response to
energy and environmental stress, both immediately upon stressor exposure
and for tens of generations thereafter. Upon energy stress at various
levels of stressor, cells exhibited fast, transient, and
amplitude-modulated responses but not frequency modulation as previously
reported. Upon environmental stress, which is mediated by the stressosome
complex, wild-type cells primarily exhibited a transient and
amplitude-modulated response. However, mutant cells producing only one of
the four paralogous RsbR stressosome proteins showed striking and
previously unseen differences. Whereas RsbRA-only cells mimicked the wild
type, RsbRC-only cells displayed a slower but sustained overall response
composed of repeated activation events in single cells.