{
  "id": 28278,
  "title": "ATP-driven conformational dynamics reveal hidden intermediates in a heterodimeric ABC transporter",
  "url": "https://urgent.news/2026/07/31/atp-driven-conformational-dynamics-reveal-hidden-intermediates-in-a",
  "topic": "health",
  "section": "Health & Medicine",
  "published": "2026-07-31T00:00:00.000Z",
  "source": {
    "name": "eLife",
    "slug": "elife",
    "url": "https://elifesciences.org/articles/110967"
  },
  "original_language": "en",
  "account": "Researchers have uncovered new insights into the inner workings of a type of transporter protein known as the heterodimeric type IV ABC transporter, specifically the TmrAB. This protein plays a crucial role in molecular machinery, similar to the human antigen transporter TAP. Traditionally, the dynamics of such proteins have been inferred from averaged measurements, but resolving individual molecule-level dynamics requires more advanced techniques.\n\nUtilizing single-molecule Förster resonance energy transfer (smFRET), scientists were able to scrutinize the ATP-driven conformational dynamics of TmrAB. By attaching fluorophores to the nucleotide-binding domains and the periplasmic gate, they validated the reliability of these reporters in tracking conformational transitions. The results showed distinct ATP-free and ATP-bound states, with a clear quantification of how ATP shifts populations between these states at physiologically relevant concentrations.\n\nThe kinetic analysis of TmrAB revealed something quite surprising: the protein remains bound to ATP for a surprisingly long period, approximately 300 milliseconds. To delve deeper, researchers employed stabilization strategies to directly observe a previously hidden state where the protein's structure is outward-facing. This state was previously masked during the normal functioning of the transporter under turnover conditions.\n\nThese findings represent the first comprehensive single-molecule characterization of the TmrAB and set the stage for a quantitative framework to explore how ATP-coupled conformational dynamics operate in heterodimeric ABC transporters. This approach offers a more detailed understanding of these essential molecular machines, paving the way for future research into their biological functions and potential therapeutic targets.",
  "summary": "ATP-binding cassette (ABC) transporters are essential molecular machines whose conformational dynamics have largely been inferred from ensemble-averaged measurements. Resolving dynamic heterogeneity and transient intermediates, however, requires single-molecule approaches. Here, we use single-molecule Förster resonance energy transfer (smFRET) to resolve ATP-driven conformational dynamics of the…",
  "key_points": [
    "Researchers use smFRET to study ATP-driven conformational dynamics of TmrAB.",
    "ATP-bound state quantified with 300ms duration, revealing hidden intermediate."
  ],
  "editors_take": null,
  "illustration": "https://urgent.news/ill/28278.png",
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}