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Updated: Aug 6, 2026
10:59
Enrichment of Bacterial Lipoproteins and Preparation of N-terminal Lipopeptides for Structural Determination by Mass Spectrometry
Published on: May 21, 2018
Structural and Functional Siderophore Remodeling by Enzymatic Delipidation
Elena Herzog1, Keishi Ishida1, Evelyn M Molloy1
1Dept. of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany.
Angewandte Chemie (International Ed. in English)
|July 24, 2026
Summary
Pandoraea bacteria produce lipopeptides that switch function from motility to iron capture via enzymatic remodeling. This discovery reveals a novel bacterial strategy for niche adaptation and nutrient acquisition.
Area of Science:
- Microbiology
- Biochemistry
- Chemical Biology
Background:
- Bacteria utilize siderophores for iron acquisition, but these molecules may have other ecological functions.
- Pandoraea species produce bifunctional lipopeptides with dual roles.
Purpose of the Study:
- To investigate the structure and function of pandorachelins produced by Pandoraea species.
- To elucidate the enzymatic remodeling process that switches lipopeptide function.
Main Methods:
- Genome mining and metabolic profiling to discover pandorachelins.
- Comprehensive NMR analysis, derivatization, and isotope labeling to determine structure.
- Genetic knockouts, enzyme reconstitution, and phenotypic assays to confirm function.
Main Results:
- Pandorachelin A is a homodetic cyclopeptide; pandorachelin B is its lipopeptide precursor.
- Enzymatic cleavage by PdnM triggers an acyl shift, converting pandorachelin B into pandorachelin A.
- This remodeling switches function from bacterial motility (surfactant activity) to iron capture (enhanced chelating capacity).
Conclusions:
- Pandoraea species employ a sophisticated mechanism to switch siderophore function for niche colonization and nutrient acquisition.
- The enzyme PdnM represents a potential antivirulence target.
- This study expands the known functional roles of bacterial siderophores.
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