Coenzyme F₄₂₀ is a redox cofactor involved in hydride transfer reactions in archaea and bacteria. Since F₄₂₀-dependent enzymes are attracting increasing interest as tools in biocatalysis, F₄₂₀ biosynthesis is being revisited. While it was commonly accepted for long that the 2-phospho-l-lactate (2-PL) moiety of F₄₂₀ is formed from free 2-PL, it was recently shown that PEP is incorporated in Actinobacteria and that the C-terminal domain of the FbiB protein, a member of the nitroreductase superfamily (NTR), converts dehydro-F₄₂₀ into saturated F₄₂₀. Outside the Actinobacteria, however, the situation is still unclear because FbiB is missing in these organisms and enzymes of the NTR family are highly diversified. Here, we show by heterologous expression and in-vitro assays that standalone NTR enzymes from Thermomicrobia exhibit dehydro-F₄₂₀ reductase activity. Metabolome analysis and proteomics studies confirmed the proposed biosynthetic pathway in Thermomicrobium roseum. These results clarify the biosynthetic route of coenzyme F₄₂₀ in a class of Gram-negative bacteria, redefine functional subgroups of the NTR superfamily, and offer an alternative for large-scale production of F₄₂₀ in E. coli in the future.

Methods are described in the original AEM publication (Braga et al., 2020).

Data from: "Biosynthesis of the redox coenzyme F420 in Thermomicrobia involves reduction by standalone nitroreductase superfamily enzymes"

This dataset contains 4 archives of LC-MS data from 4 different experiments:

* Metabolite analysis of Thermomicrobium roseum
* Nitroreductase - in-vivo coexpression in E. coli
* Nitroreductase from Thermomicrobium roseum - in-vitro assay
* Proteomics of Thermomicrobium roseum

LC-MS data were converted to mzML format before upload. All metadata can be found in the original publication.