A novel quinone biosynthetic pathway illuminates the evolution of aerobic metabolism.

ABSTRACT: The dominant organisms in modern oxic ecosystems rely on respiratory quinones with high redox potential (HPQs) for electron transport in aerobic respiration and photosynthesis. The diversification of quinones, from low redox potential (LPQ) in anaerobes to HPQs in aerobes, is assumed to have followed Earth's surface oxygenation ~2.3 billion years ago. However, the evolutionary origins of HPQs remain unresolved. Here, we characterize the structure and biosynthetic pathway of an ancestral HPQ, methyl-plastoquinone (mPQ), that is unique to bacteria of the phylum Nitrospirota. mPQ is structurally related to the two previously known HPQs, plastoquinone from Cyanobacteriota/chloroplasts and ubiquinone from Pseudomonadota/mitochondria, respectively. We demonstrate a common or

SUBMITTER: Elling FJ 

PROVIDER: S-EPMC11874023 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature