Oral Presentation 51st Lorne Proteins Conference 2026

Structural basis of bacterial nickel import by Type I ABC transporters (132615)

Sarah L. Mueller 1 , Simon H. J. Brown 2 , Scarlett Cox 1 , Emily J. Furlong 1
  1. Research School of Biology, Australian National University, Canberra, ACT, Australia
  2. School of Chemistry and Molecular Bioscience, Molecular Horizons, and ARC Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW, Australia

Nickel is an essential cofactor for the function of at least nine fundamental bacterial enzyme families, including ureases, NiFe-hydrogenases and carbon monoxide dehydrogenases.1 In many bacteria, nickel transport across the inner membrane is mediated by Type I ATP-binding cassette (ABC) transporter systems.1 These systems are composed of five proteins: one periplasmic nickel binding protein, heterodimeric transmembrane domains and heterodimeric nucleotide binding domains. Here we present a 2.2 Å cryogenic electron microscopy structure of the primary nickel transporter, YntBCDE, from the uropathogen Proteus mirabilis in an inward-facing conformation and an initial 4 Å map of the entire YntABCDE complex in an outward-facing conformation. Our analysis highlights conserved key residues for nickel transport in the transmembrane domains of nickel ABC transporters and distinct features in the heterodimeric nucleotide binding domains.

  1. Waldron, K.J. and N.J. Robinson, Nat Rev Microbiol, 2009.