University of Veterinary Medicine Vienna - Research portal

Diagrammed Link to Homepage University of Veterinary Medicine, Vienna

Selected Publication:

Open Access Logo

Type of publication: Journal Article
Type of document: Full Paper

Year: 2021

Authors: Walser, V; Kranzler, M; Ehling-Schulz, M; Stark, TD; Hofmann, TF

Title: Structure Revision of Isocereulide A, an Isoform of the Food Poisoning Emetic Bacillus cereus Toxin Cereulide.

Source: Molecules. 2021; 26(5):1360

Authors Vetmeduni Vienna:

Ehling-Schulz Monika
Kranzler Markus

Vetmed Research Units
Institute of Microbiology, Functional Microbiology Division

The emetic Bacillus cereus toxin cereulide presents an enormous safety hazard in the food industry, inducing emesis and nausea after the consumption of contaminated foods. Additional to cereulide itself, seven structurally related isoforms, namely the isocereulides A-G, have already been elucidated in their chemical structure and could further be identified in B. cereus contaminated food samples. The newly performed isolation of isocereulide A allowed, for the first time, 1D- and 2D-NMR spectroscopy of a biosynthetically produced isocereulide, revealing results that contradict previous assumptions of an l-O-Leu moiety within its chemical structure. By furthermore applying posthydrolytical dipeptide analysis, amino acid and α-hydroxy acid analysis by means of UPLC-ESI-TOF-MS, as well as MSn sequencing, the structure of previously reported isocereulide A could be corrected. Instead of the l-O-Leu as assumed to date, one l-O-Ile unit could be verified in the cyclic dodecadepsipeptide, revising the structure of isocereulide A to [(d-O-Leu-d-Ala-l-O-Val-l-Val)2(d-O-Leu-d-Ala-l-O-Ile-l-Val)].

© University of Veterinary Medicine ViennaHelp and DownloadsAccessibility statement