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Abstract Volatile Organic Compounds (VOCs) are a diverse collection of molecules critical to cell metabolism, food web interactions, and atmospheric chemistry. The eukaryotic coccolithophoreGephyrocapsa huxleyi, an abundant coastal eukaryotic phytoplankter, forms massive blooms in coastal upwelling regions, which are often terminated by viruses (EhVs).G. huxleyiproduces organosulfur VOCs such as dimethyl sulfide (DMS) and halogenated metabolites that play key roles in atmospheric chemistry. Here we resolved the role of lytic viral infection by EhV207 on VOC production of the model strainG. huxleyiCCMP374. Our analysis identified 79 VOCs significantly impacted by viral infection, particularly during cell lysis, with sulfur containing VOCs like DMS dominating the profiles. Viral lysis results in a nearly six-fold increase in VOC production and generated a previously unrecognized range of VOCs, including 15 sulfur, 22 nitrogen, 2 phosphorus, 19 oxygen and 17 halogen-containing compounds. These findings reveal that viral infection ofG. huxleyireleases VOCs which are much more diverse than previously recognized. We further show that EhV207 primarily accelerates existing metabolic processes inG. huxleyiand facilitates the release of pre-existing intracellular VOCs rather than inducing novel biochemical pathways. This wide range of VOCs may be produced on a massive scale during coccolithophore bloom-and-bust cycles, with important impacts on coastal biogeochemistry and surface ocean/atmosphere interactions.
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Volatile Organic Compound Metabolism on Early Earth
Abstract Biogenic volatile organic compounds (VOCs) constitute a significant portion of gas-phase metabolites in modern ecosystems and have unique roles in moderating atmospheric oxidative capacity, solar radiation balance, and aerosol formation. It has been theorized that VOCs may account for observed geological and evolutionary phenomena during the Archaean, but the direct contribution of biology to early non-methane VOC cycling remains unexplored. Here, we provide an assessment of all potential VOCs metabolized by the last universal common ancestor (LUCA). We identify enzyme functions linked to LUCA orthologous protein groups across eight literature sources and estimate the volatility of all associated substrates to identify ancient volatile metabolites. We hone in on volatile metabolites with confirmed modern emissions that exist in conserved metabolic pathways and produce a curated list of the most likely LUCA VOCs. We introduce volatile organic metabolites associated with early life and discuss their potential influence on early carbon cycling and atmospheric chemistry.
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- Award ID(s):
- 2045332
- PAR ID:
- 10524330
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Journal of Molecular Evolution
- Volume:
- 92
- Issue:
- 5
- ISSN:
- 0022-2844
- Format(s):
- Medium: X Size: p. 605-617
- Size(s):
- p. 605-617
- Sponsoring Org:
- National Science Foundation
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