Detection of GroEL in activated sludge: a model for detection of system stress

GroEL is a ubiquitous constitutively synthesized protein that is also stres s inducible. Activated sludge, which is a standard biological process used in wastewater treatment systems, is made up of a diverse microbial consorti um. The synthesis of GroEL in activated sludge was significantly induced af ter heat (42 degrees C) shock. The increased level of GroEL expression was shown to be due to de novo protein synthesis. We have demonstrated a method which shows that stress proteins can be detected in activated sludge, and propose their use as specific indicators of system stress.