Activity-Based Protein Profiling Identifies Protein Disulfide-Isomerases as Target Proteins of the Volatile Salinilactones

authored by: Karoline Jerye, Helko Lüken, Anika Steffen, Christian Schlawis, Lothar Jänsch, Stefan Schulz, Mark Brönstrup
Abstract: The salinilactones, volatile marine natural products secreted from Salinispora arenicola, feature a unique [3.1.0]-lactone ring system and cytotoxic activities through a hitherto unknown mechanism. To find their molecular target, an activity-based protein profiling with a salinilactone-derived probe is applied that disclosed the protein disulfide-isomerases (PDIs) as the dominant mammalian targets of salinilactones, and thioredoxin (TRX1) as secondary target. The inhibition of protein disulfide-isomerase A1 (PDIA1) and TRX1 is confirmed by biochemical assays with recombinant proteins, showing that (1S,5R)-salinilactone B is more potent than its (1R,5S)-configured enantiomer. The salinilactones bound covalently to C53 and C397, the catalytically active cysteines of the isoform PDIA1 according to tandem mass spectrometry. Reactions with a model substrate demonstrated that the cyclopropyl group is opened by an attack of the thiol at C6. Fluorophore labeling experiments showed the cell permeability of a salinilactone-BODIPY (dipyrrometheneboron difluoride) conjugate and its co-localization with PDIs in the endoplasmic reticulum. The study is one of the first to pinpoint a molecular target for a volatile microbial natural product, and it demonstrates that salinilactones can achieve high selectivity despite their small size and intrinsic reactivity.
Organisation(s): Centre of Biomolecular Drug Research (BMWZ)
External Organisation(s): Helmholtz Centre for Infection Research (HZI)
Technische Universität Braunschweig
German Center for Infection Research (DZIF)
Type: Article
Journal: Advanced science
Volume: 11
No. of pages: 11
ISSN: 2198-3844
Publication date: 15.05.2024
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Medicine (miscellaneous), General Chemical Engineering, General Materials Science, Biochemistry, Genetics and Molecular Biology (miscellaneous), General Engineering, General Physics and Astronomy
Sustainable Development Goals: SDG 14 - Life Below Water
Electronic version(s): https://doi.org/10.1002/advs.202309515 (Access: Open)

BibTeX

@article{069ed6c8f6ca460a98262ba38c056dd5,
title = "Activity-Based Protein Profiling Identifies Protein Disulfide-Isomerases as Target Proteins of the Volatile Salinilactones",
abstract = "The salinilactones, volatile marine natural products secreted from Salinispora arenicola, feature a unique [3.1.0]-lactone ring system and cytotoxic activities through a hitherto unknown mechanism. To find their molecular target, an activity-based protein profiling with a salinilactone-derived probe is applied that disclosed the protein disulfide-isomerases (PDIs) as the dominant mammalian targets of salinilactones, and thioredoxin (TRX1) as secondary target. The inhibition of protein disulfide-isomerase A1 (PDIA1) and TRX1 is confirmed by biochemical assays with recombinant proteins, showing that (1S,5R)-salinilactone B is more potent than its (1R,5S)-configured enantiomer. The salinilactones bound covalently to C53 and C397, the catalytically active cysteines of the isoform PDIA1 according to tandem mass spectrometry. Reactions with a model substrate demonstrated that the cyclopropyl group is opened by an attack of the thiol at C6. Fluorophore labeling experiments showed the cell permeability of a salinilactone-BODIPY (dipyrrometheneboron difluoride) conjugate and its co-localization with PDIs in the endoplasmic reticulum. The study is one of the first to pinpoint a molecular target for a volatile microbial natural product, and it demonstrates that salinilactones can achieve high selectivity despite their small size and intrinsic reactivity.",
keywords = "activity-based protein profiling, natural products, protein disulfide-isomerases, salinilactones, volatiles",
author = "Karoline Jerye and Helko L{\"u}ken and Anika Steffen and Christian Schlawis and Lothar J{\"a}nsch and Stefan Schulz and Mark Br{\"o}nstrup",
note = "Publisher Copyright: {\textcopyright} 2024 The Authors. Advanced Science published by Wiley-VCH GmbH.",
year = "2024",
month = may,
day = "15",
doi = "10.1002/advs.202309515",
language = "English",
volume = "11",
journal = "Advanced science",
issn = "2198-3844",
publisher = "Wiley-VCH Verlag",
number = "18",
}