Phyletic Distribution and Diversification of the Phage Shock Protein Stress Response System in Bacteria and Archaea
Philipp F. Popp, Vadim M. Gumerov, Ekaterina P. Andrianova, Lisa Bewersdorf, Thorsten Mascher, Igor B. Zhulin, Diana Wolf
Abstract
The PspA protein domain is found in all domains of life, highlighting its central role in Psp networks. To date, all insights into the core functions of Psp responses derive mainly from protein network blueprints representing only three bacterial phyla. Despite large overlaps in function and regulation, the evolutionary diversity of Psp networks remains largely elusive. Here, we present an unbiased protein domain- and genomic context-centered approach that describes and classifies Psp systems. Our results suggest so-far-unknown Psp-associated roles with other protein networks giving rise to new functions. We demonstrate the applicability of our approach by dissecting the Psp protein network present in Bacillus subtilis and demonstrate Psp domains working in concert with other cell envelope stress response systems. We find that the Psp-like protein universe reflects a surprising diversity within the bacterial and archaeal microbial world.