Stress response in Actinobacillus actinomycetemcomitans: induction of general and specific stress proteins.

Stress proteins are highly conserved proteins that are essential for cell survival. In this study, the induction of general and specific stress proteins in Actinobacillus actinomycetemcomitans cells subjected to different stress conditions was evaluated by two-dimensional SDS-PAGE analysis. Twenty-eight (up- or down)regulated proteins, including DnaK and GroEL proteins, were identified as general stress proteins. In addition, eighteen regulated proteins were classified as pH stress-specific proteins, ten as acid stress-specific proteins, five as alkaline stress-specific proteins, three as heat stress-specific proteins, and ten as acid/heat stress-specific proteins. Further proteomic studies are required to determine the exact nature of the proteins regulated during the stress response of A. actinomycetemcomitans.