Preprint
Bacterial pathogen deploys iminosugar galactosyrin to manipulate plant glycobiology
- Abstract:
- The extracellular space (apoplast) of plants is an important molecular battleground during infection by many pathogens. We previously found that a plant-secreted β-galactosidase BGAL1 acts in immunity by facilitating the release of immunogenic peptides from bacterial flagellin and that Pseudomonas syringae suppresses this enzyme by producing a small molecule inhibitor called galactosyrin. Here, we elucidated the structure and biosynthesis of galactosyrin and uncovered its multifunctional roles during infection. Structural elucidation by cryo-EM and chemical synthesis revealed that galactosyrin is an iminosugar featuring a unique geminal diol attached to the pyrrolidine moiety that mimics galactose binding to the β-galactosidase active site. Galactosyrin biosynthesis branches off from purine biosynthesis and involves three enzymes of which the first is a reductase that is unique in iminosugar biosynthesis. Besides inhibiting BGAL1 to avoid detection, galactosyrin also changes the glycoproteome and metabolome of the apoplast. The manipulation of host glycobiology may be common to plant-associated bacteria that carry putative iminosugar biosynthesis clusters.
- Publication status:
- Published
- Peer review status:
- Not peer reviewed
Actions
Authors
+ Wellcome Trust
More from this funder
- Funder identifier:
- https://ror.org/029chgv08
- Grant:
- 206422/Z/17/Z
- 203141/Z/16/Z
+ European Research Council
More from this funder
- Funder identifier:
- https://ror.org/0472cxd90
- Grant:
- 101019324
+ National Institutes of Health
More from this funder
- Funder identifier:
- https://ror.org/01cwqze88
- Grant:
- U54AI170791-7522
+ Biotechnology and Biological Sciences Research Council
More from this funder
- Funder identifier:
- https://ror.org/00cwqg982
- Grant:
- BB/R017913/1
- BB/T015128/1
- BB/M011224/1
- Preprint server:
- bioRxiv
- Publication date:
- 2025-02-14
- DOI:
- Language:
-
English
- Pubs id:
-
2091059
- Local pid:
-
pubs:2091059
- Deposit date:
-
2025-04-29
Terms of use
- Copyright holder:
- Sanguankiattichai et al.
- Copyright date:
- 2025
- Rights statement:
- The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY 4.0 International license.
- Licence:
- CC Attribution (CC BY)
If you are the owner of this record, you can report an update to it here: Report update to this record