Cyclic Isothiocyanate Goitrin Impairs Lotus japonicus Nodulation, Affects the Proteomes of Nodules and Free Mesorhizobium loti , and Induces the Formation of Caffeic Acid Derivatives in Bacterial Cultures

• Published in: Plants (Basel) Vol. 13; no. 20; p. 2897
• Main Authors: Jeong, Seungwoo, Schütz, Vadim, Demir, Fatih, Preusche, Matthias, Huesgen, Pitter, Bigler, Laurent, Kovacic, Filip, Gutbrod, Katharina, Dörmann, Peter, Schulz, Margot
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01-10-2024; MDPI
• Subjects: Abscisic acid; Abscission; Acidic soils; Amino acids; Bacteria; Beans; Biosynthesis; Brassica glucosinolate; Caffeic acid; caftaric acid; Chemical properties; chicoric acid; Comparative analysis; Complex formation; cyclic isothiocyanate goitrin; Environmental aspects; Exudation; Fungi; Growth; Injury prevention; Leaves; Legumes; Lotus (Legumes); Lotus japonicus; Measurement; Mesorhizobium loti; Microorganisms; Mimosaceae; Molecular modelling; Nitrogen-fixing microorganisms; Nodulation; Nodules; Pathogenesis; Physiological aspects; Plant layout; Polyphenols; Protein transport; Proteins; Proteolysis; Proteomes; Senescence; Signal transduction; Soil microorganisms; Spectrometry; Symbiosis; Thiocyanates; Germany; Massachusetts; caftaric acid; proteomics; cyclic isothiocyanate goitrin; Brassica glucosinolate; Mesorhizobium loti; chicoric acid; nodulation; Lotus japonicus
• ISSN: 2223-7747; 2223-7747
• DOI: 10.3390/plants13202897

The continuous release of glucosinolates into the soil by Brassicaceae root exudation is a prerequisite to maintaining toxic levels of breakdown products such as isothiocyanates (ITCs). ITCs influence plant and microbial diversity in ecosystems, while fungi and Rhizobiaceae are particularly injured. Studies explaining the molecular mechanisms of the negative effects are presently limited. Therefore, we investigated the early effects of cyclic ITC goitrin on proteomes of the host and symbiotic
in the nodules of
and of free-living bacteria. In the nodules, many host proteins had a higher abundance, among them, peroxidases and pathogenesis-related PR-10 proteins functioning in the abscisic-acid-activated signaling pathway. In the microsymbiont, transporter proteins as a prominent group are enhanced; some proteins involved in N-fixation decreased. The proteomes give a report about the loss of immunity suppression resulting in the termination of symbiosis, which initiates nodule senescence. Free-living
are severely damaged, indicated, i.a., by a decrease in transporter proteins, the assumed candidates for goitrin protein complex formation, and high proteolysis. The production of chicoric acid by the accompanying bacteria is inhibitory for
but connected to goitrin elimination, as confirmed by mass spectrometric (MS) analysis. In summary, the nodulation process is severely affected by goitrin, causing nodule dysfunction and failed nodule development. N deficiency conditions leads to yellowish leaves and leaf abscission.