A novel quinone biosynthetic pathway illuminates the evolution of aerobic metabolism


Loading...

Date

2025-02-25

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

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 origin of the three HPQ biosynthetic pathways that predates the emergence of Nitrospirota, Cyanobacteriota, and Pseudomonadota. An ancestral HPQ biosynthetic pathway evolved ≥ 3.4 billion years ago in an extinct lineage and was laterally transferred to these three phyla ~2.5 to 3.2 billion years ago. We show that Cyanobacteriota and Pseudomonadota were ancestrally aerobic and thus propose that aerobic metabolism using HPQs significantly predates Earth's surface oxygenation. Two of the three HPQ pathways were later obtained by eukaryotes through endosymbiosis forming chloroplasts and mitochondria, enabling their rise to dominance in modern oxic ecosystems.

Publication status

published

Editor

Book title

Volume

122 (8)

Pages / Article No.

Publisher

National Academy of Sciences

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

biosynthesis ; electron transport chain; great oxygenation event; nitrospirota; quinone 

Organisational unit

09743 - Hemingway, Jordon / Hemingway, Jordon check_circle

Notes

Funding

946150 - Reconstructing the Effect of Sulfide Respiration on Global Redox State: Insights from Experiments, Obeservations, and Models (EC)

Related publications and datasets