Tryptophanol enhances nitrogen assimilation in marine diatoms.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41904145.
- Also identified by DOI 10.1038/s41467-026-71191-8.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Diatoms exhibit high competitive capacity in nitrogen assimilation, but the underlying mechanisms remain unclear. Here, we identify a non-ribosomal peptide synthase-like gene (PtNRPS1) with an atypical domain structure (A-T-R<sub>1</sub>-R<sub>2</sub>) in the marine diatom Phaeodactylum tricornutum, crucial for short-term nitrogen assimilation. In vitro enzyme assays show PtNRPS1 catalyzes conversion of L-tryptophan to tryptophanol, a tryptophan-derived indole compound that promotes diatom growth at concentrations far lower than indole-3-acetic acid. Transcriptomic, metabolomic analyses, and stable-isotope analyses indicate tryptophanol enhances short-term nitrogen assimilation. CRISPR-Cas9 knockout of PtNRPS1 abolishes tryptophanol biosynthesis and reduces nitrogen-assimilation enzymes activities, which are restored by exogenous tryptophanol. PtNRPS1 overexpression results in delayed but sustained enzyme elevation. Global distribution of PtNRPS1 homologues in stramenopiles positively correlates with nitrogen-assimilation gene abundance. Our findings suggest tryptophanol, synthesized by a diatom NRPS, accelerates nitrogen assimilation, providing a competitive edge in oceanic nitrogen acquisition.