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Cited by 3Microbial Community Ecology and PhysiologyMicrobial metabolism and enzyme functionBacterial Genetics and Biotechnology

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Conserved pathway for homarine catabolism in environmental bacteria

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Ferrer-González, Frank X., Heal, Katherine R., Sacks, Joshua S., Romero-Maysonet, Yarinet, Finch, Anna H., Carlson, Laura T., Coe, Lisa S. Y., Bartolek, Zinka, Luthy, Claudia B., Gaffney, Moira P., Angier, Sabine K., Flynn, Samantha E., Bachmann Gómez, Chiara I., Dunn, Jensen M. L., Bay, Kenzie J., Yamamoto, Lia A., Tien, Matthew Z., Armbrust, E. Virginia, Durham, Bryndan P., Sosa, Oscar A., Ingalls, Anitra E.·2026·Nature Microbiology
DOI 10.1038/s41564-026-02313-7

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Abstract

Homarine (N-methylpicolinic acid) is a ubiquitous marine metabolite produced by phytoplankton and noted for its infochemical properties among marine animals, yet its microbial degradation pathways are uncharacterized. Here we identify a conserved operon (homABCDER) that mediates homarine catabolism in bacteria using comparative transcriptomics, mutagenesis and targeted knockouts. Phylogenetic and genomic analyses show that this operon is distributed across abundant bacterial clades, including coastal copiotrophs (for example, Rhodobacterales) and open-ocean oligotrophs (for example, SAR11, SAR116), and in genomes from non-marine environments. High-resolution mass spectrometry revealed N-methylglutamic acid and glutamic acid as key metabolic products of homarine in both model and natural systems, with N-methyl-glutamate dehydrogenase catalysing their conversion. Metatranscriptomics showed responsive and in situ expression of hom genes aligned with homarine availability. These findings uncover the genetic and metabolic basis of homarine degradation, establish its ecological relevance and highlight homarine as a versatile growth substrate that feeds into central metabolism via glutamic acid in diverse marine bacteria.

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Metadata

Authors
Ferrer-González, F. X., Heal, K. R., Sacks, J. S., Romero-Maysonet, Y., Finch, A. H., Carlson, L. T., Coe, L. S. Y., Bartolek, Z., Luthy, C. B., Gaffney, M. P., Angier, S. K., Flynn, S. E., Bachmann Gómez, C. I., Dunn, J. M. L., Bay, K. J., Yamamoto, L. A., Tien, M. Z., Armbrust, E. V., Durham, B. P., Sosa, O. A., & Ingalls, A. E.
Affiliations
  • University of Washington (US)
  • Pacific Northwest National Laboratory (US)
  • University of Puget Sound (US)
  • University of Florida (US)
  • Harvard University (US)
  • Whitman College (US)
Corresponding author
  • Sosa, Oscar A.
  • Ingalls, Anitra E.
ORCID
Venue
Nature Microbiology
Publisher
Springer Science and Business Media LLC
Published
2026-03-30
Volume
11
Issue
6
Pages
1531-1546
ISSN
2058-5276 (ISSN-L)
DOI
10.1038/s41564-026-02313-7
OpenAlex
W7143336992
Cited by
3
References
2
Citations by year
2026: 3
FWCI
10.45
Type
journal article
Language
en
Open access
Licence
Locations
  • Nature Microbiology (publishedVersion, cc-by-nc-nd)
  • Research Square (acceptedVersion, cc-by)
  • PubMed (publishedVersion)
  • PubMed Central (publishedVersion, cc-by-nc-nd)
Topics
  • Physical Sciences › Environmental Science › Ecology › Microbial Community Ecology and Physiology
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Microbial metabolism and enzyme function
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Bacterial Genetics and Biotechnology
Keywords
homarine, bacterial catabolism, glutamate, marine bacteria, SAR11, Rhodobacterales, phylogenetic distribution, marine metabolites, semiochemicals, bacterial gene expression
MeSH terms
Bacteria, Operon, Phylogeny, Glutamic Acid, Gene Expression Profiling, Metabolic Networks and Pathways, Gene Knockout Techniques

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