Bacterial lactonases ZenA with noncanonical structural features hydrolyze the mycotoxin zearalenone

DOI: 10.1021/acscatal.4c00271

Authors: Sebastian Fruhauf (dsm-firmenich Animal Nutrition and Health R&D Center Tulln) , Dominic Pühringer (University of Vienna) , Michaela Thamhesl (dsm-firmenich Animal Nutrition and Health R&D Center Tulln) , Patricia Fajtl (dsm-firmenich Animal Nutrition and Health R&D Center Tulln) , Elisavet Kunz-Vekiru (University of Natural Resources and Life Sciences Vienna (BOKU)) , Andreas Höbartner-Gussl (dsm-firmenich Animal Nutrition and Health R&D Center Tulln) , Gerd Schatzmayr (dsm-firmenich Animal Nutrition and Health R&D Center Tulln) , Gerhard Adam (University of Natural Resources and Life Sciences Vienna (BOKU)) , Jiri Damborsky (Masaryk University; St. Anne’s University Hospital Brno) , Kristina Djinovic-Carugo (University of Vienna; University of Ljubljana) , Zbynek Prokop (Masaryk University; St. Anne’s University Hospital Brno) , Wulf-Dieter Moll (dsm-firmenich Animal Nutrition and Health R&D Center Tulln)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Acs Catalysis , VOL 49 , PAGES 3392 - 3410

State: Published (Approved)
Published: February 2024

Abstract: Zearalenone (ZEN) is a mycoestrogenic polyketide produced by Fusarium graminearum and other phytopathogenic members of the genus Fusarium. Contamination of cereals with ZEN is frequent, and hydrolytic detoxification with fungal lactonases has been explored. Here, we report the isolation of a bacterial strain, Rhodococcus erythropolis PFA D8–1, with ZEN hydrolyzing activity, cloning of the gene encoding α/β hydrolase ZenA encoded on the linear megaplasmid pSFRL1, and biochemical characterization of nine homologues. Furthermore, we report site-directed mutagenesis as well as structural analysis of the dimeric ZenARe of R. erythropolis and the more thermostable, tetrameric ZenAScfl of Streptomyces coelicoflavus with and without bound ligands. The X-ray crystal structures not only revealed canonical features of α/β hydrolases with a cap domain including a Ser-His-Asp catalytic triad but also unusual features including an uncommon oxyanion hole motif and a peripheral, short antiparallel β-sheet involved in tetramer interactions. Presteady-state kinetic analyses for ZenARe and ZenAScfl identified balanced rate-limiting steps of the reaction cycle, which can change depending on temperature. Some new bacterial ZEN lactonases have lower KM and higher kcat than the known fungal ZEN lactonases and may lend themselves to enzyme technology development for the degradation of ZEN in feed or food.

Journal Keywords: zearalenone; mycotoxin; lactonase; carboxylesterase; hydrolase; kinetics; presteady-state; Rhodococcus erythropolis

Diamond Keywords: Fungi; Cereal Crops; Enzymes; Bacteria

Subject Areas: Biology and Bio-materials, Chemistry, Food Science


Instruments: I03-Macromolecular Crystallography , I04-Macromolecular Crystallography

Other Facilities: ID23-1, ID23-2, ID-30B, ID29, ID30A3 at ERSF

Added On: 21/02/2024 11:56

Discipline Tags:

Pathogens Biochemistry Agriculture & Fisheries Genetics Catalysis Chemistry Structural biology Life Sciences & Biotech Food Science

Technical Tags:

Diffraction Macromolecular Crystallography (MX)