biostudies-literatureLin ZNIGMS NIH HHS1664275https://www.ebi.ac.uk/biostudies/studies/S-EPMC12893633biostudies-literatureUnknown12Halogenated molecules produced by marine algae are thought to be defensive secondary metabolites. The extraordinarily high concentration of bromoform in the seaweed <i>Asparagopsis</i>-up to 8% dry tissue weight-challenges the exclusivity of this paradigm. In this report, we provide evidence that the <i>mbb1</i> gene which encodes the bromoform producing halogenase is among the most highly transcribed genes in <i>Asparagopsis</i> tissue, with the resulting Mbb1 protein abundance rivaling that of enzymes involved in photosynthesis and carbon fixation. When the seaweed was stressed with light, transcripts for both <i>mbb1</i> and for proteins involved in photosynthesis were significantly downregulated. Conversely, heat stress modestly upregulated some photosynthesis genes but had no impact oFrontiers in Marine ScienceDetection of unusually high transcriptomic and proteomic abundance of bromoform-synthesizing halogenase in marine macroalgae &lt;i&gt;Asparagopsis taxiformis&lt;/i&gt;.PMC12893633R35 GM142882Smith JEZhou LIslam SSchmidt EWHargrave MSAgarwal VLin ZSingh RXie RfalseDetection of unusually high transcriptomic and proteomic abundance of bromoform-synthesizing halogenase in marine macroalgae &lt;i&gt;Asparagopsis taxiformis&lt;/i&gt;.Halogenated molecules produced by marine algae are thought to be defensive secondary metabolites. The extraordinarily high concentration of bromoform in the seaweed <i>Asparagopsis</i>-up to 8% dry tissue weight-challenges the exclusivity of this paradigm. In this report, we provide evidence that the <i>mbb1</i> gene which encodes the bromoform producing halogenase is among the most highly transcribed genes in <i>Asparagopsis</i> tissue, with the resulting Mbb1 protein abundance rivaling that of enzymes involved in photosynthesis and carbon fixation. When the seaweed was stressed with light, transcripts for both <i>mbb1</i> and for proteins involved in photosynthesis were significantly downregulated. Conversely, heat stress modestly upregulated some photosynthesis genes but had no impact o2025-01-01T00:00:00Z20252026-07-15T15:36:06.235Z2026-07-06T03:10:59.559ZS-EPMC128936334168464410.3389/fmars.2025.1664275