Structural and Functional Investigation of Tight Adhesion Locus Proteins in Bdellovibrio bacteriovorus.

Bdellovibrio bacteriovorus is a Gram-negative deltaproteobacterium and bacterial predator, capable of killing many Gram-negative prey species, including known pathogens. Bdellovibrio predatory lifecycle, involving invading host periplasmic space to breakdown and absorb prey nutrients, enables Bdellovibrio to efficiently kill prey species that are resistant to antibiotic treatment. Several studies have identified potential for Bdellovibrio to be used as an antimicrobial agent in healthcare and food security settings.
This project focuses on a ten gene tight adherence (TAD) operon and four gene cryptic locus with hypothetical functions in the assembly of type IVb fimbriae-like pili. The mechanism of action of these TAD pilus assembly proteins remains poorly understood, with previous studies in Bdellovibrio focusing on Type IVb pilus genes and an absence of structural studies of TAD pilus components. However, previous studies have shown these fimbriae-like pilins are expressed in both HI and attack phase and are essential to prey recognition. This study aims to conduct structural investigation of key components of the TAD and cryptic loci proteins, alongside biochemical assays to determine their function and mechanism of action in pilus assembly. Improving knowledge of the structures and mechanistic role of proteins in key predatory processes is a key step in understanding use of Bdellovibrio as an antimicrobial agent.