Poster Presentation The 42nd Lorne Conference on Protein Structure and Function 2017

Dissecting the distinct functional roles of the POTRA and b-barrel domains of BamA and TamA. (#174)

Rebecca Bamert 1 , Christopher Stubenrauch 1 , Takuya Shiota 1 , Chaille Webb 1 , Matthew Belousoff 1 , Robert Goode 2 , Ralf Schittenhelm 2 , Richard Zimmerman 3 , Martin Jung 3 , Trevor Lithgow 1
  1. Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, Victoria, Australia
  2. Monash Biomedical Proteomics Facility, Monash University, Melbourne, Victoria, Australia
  3. Medical Biochemistry and Molecular Biology, Saarland University, Hamburg, Germany

The BAM complex is responsible for the correct assembly and localisation of the majority of Outer Membrane Proteins (OMPs) essential to Gram negative bacterial viability and integrity. In the case of a subset of more challenging OMPs the TAM complex also assists in this process. Both BamA and TamA comprise the main component of these respective complexes, and both consist of N-terminal POTRA domains followed by a C-terminal beta-barrel. The BAM and TAM complexes localise to the bacterial outer membrane where they integrate folded substrate proteins into the outer membrane environment.

This study explores the roles of these domains in the assembly of common substrates. By probing a peptide spot array consisting of beta-strands from a common substrate protein with full-length BamA and TamA, as well as domains thereof, insights into the mechanism of action of these proteins can be gained. Coupled with cross-linking of substrate peptides to BamA and TamA, bioinformatics approaches and chimeric studies, similarities and differences in mechanisms shall come to light, as well as the functions of these distinct yet conserved domain features.