{
  "id": 6850539,
  "title": "Cyanophage CP12 Rewires Host Carbon Regulation through Interface Remodeling and Redox Buffering",
  "url": "https://urgent.news/2026/09/11/cyanophage-cp12-rewires-host-carbon-regulation-through-interface",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-11T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.10.750766v1?rss=1"
  },
  "original_language": "en",
  "account": "Cyanophages, such as CP12, have the ability to rewire the carbon regulation of their host picocyanobacteria by remodeling interfaces and buffering redox states. The intrinsically disordered Calvin cycle protein 12 (CP12) within cyanobacteria assembles enzymes like glyceraldehyde-3-phosphate dehydrogenase (GAP2) and phosphoribulokinase (PRK) into a dark complex, but the role of CP12 homologs from cyanophages in modulating redox-sensitive partners is not well understood. A study examined viral CP12 across sequence, structure, and post-translational modification complexities to clarify how these viral proteins impact host metabolism during infection. Analysis revealed that viral CP12 maintains interface-dominated positions while altering partner-facing chemistry to include charged and geometry-modulating features. Molecular dynamics simulations of Prochlorococcus MED4 and the cyanophage P-HM2 showed that phage CP12 preserves assembly while strengthening contacts with PRK and reducing the burial of GAP2 in the interface. Examining redox proteomics in MED4 under light disturbance, researchers identified coordinated cysteine oxidation across CP12 and GAP2, guiding molecular dynamics to explore thiol post-translational modification states. Conformational changes in CP12 and GAP2 increased with the load of post-translational modifications, primarily affecting GAP2. The thiol PTM at GAP2 imposed the largest binding-energy cost for CP12, which was buffered by P-HM2 CP12, resulting in smaller binding-energy penalties compared to the host CP12. This study demonstrates that CP12, as a regulatory mimetic, can adjust host carbon regulation during infection by influencing sequence-driven chemistry, interface dynamics, and redox PTM responsiveness to light.",
  "summary": "Picocyanobacteria drive ocean carbon fixation, and cyanophages reshape host metabolism during infection. In cyanobacteria, the intrinsically disorder Calvin cycle protein 12 (CP12) assembles glyceraldehyde-3-phosphate dehydrogenase (GAP2) and phosphoribulokinase (PRK) into the inhibitory dark complex, yet how phage CP12 homologs modulate redox-sensitive partners remains unclear. Here, we examined…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "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."
}