Evolutionary behaviour of bacterial prion-like proteins

Area of Science:

• Evolutionary biology
• Microbial genetics
• Protein science

Background:

• Prions in eukaryotes are associated with diseases and biological functions.
• Bacterial prion-forming proteins, such as Clostridium botulinum Rho, are emerging research areas.
• The evolutionary distribution of bacterial prions is not well understood.

Purpose of the Study:

• To analyze the evolutionary distribution of the Rho prion-forming domain across bacteria.
• To determine if wide-ranging evolutionary sporadicity is typical for bacterial prion-like domains.
• To assess the prevalence and distribution of prion-like protein domains in bacteria.

Main Methods:

• Bioinformatic analysis of the Rho prion-forming domain's conservation across bacterial species.
• Derivation of a 'coverage' metric (C) to quantify domain prevalence within its evolutionary range.
• Comparative analysis of >60 prion-like protein domain families across multiple bacterial phyla.

Main Results:

• The Rho prion-forming domain exhibits sporadic conservation across the Clostridium genus and bacteria generally.
• This domain spans at least eight different bacterial phyla, demonstrating wide evolutionary reach.
• Bacterial prion-like domains frequently occur across multiple phyla but sample a low fraction of species within their range.
• The Rho family is among the top three most widely distributed prion-like domain families by phyla count.

Conclusions:

• Wide-ranging evolutionary sporadicity is a common characteristic of bacterial prion-like protein domains.
• These findings have implications for understanding bacterial evolution and prion protein research.
• Further experimental investigation into bacterial prion-forming proteins is warranted.