Developing Fhb7-Derived Enzymes with High Thermostability for Detoxification of T-2 Toxin through Ancestral Sequence Reconstruction
Jun Yang, Yuling Zhu, Yunxi Han, Han Ke, Jing Zhang, Ming-Wei Wang, Xiaoguang Lei*
ACS Catal. 2025, 15, 11664–11672
Trichothecenes, particularly T-2 toxin (T-2), pose significant threats to food safety as well as to both animal and human health. Although Fhb7 and its variants have been utilized for deoxynivalenol degradation, no enzyme with efficient T-2 degradation activity has been reported. Herein, we generated five enzymes derived from Fhb7 that are capable of T-2 degradation via ancestral sequence reconstruction. Among these, N1, N2, and N4 exhibited superior catalytic activity toward T-2 compared to the parent enzyme Fhb7 and its variants. Structural analyses revealed that residue F27 provides a hydrophobic environment for accommodation of the unique 3-methylbutyryl group of T-2. In addition, the long insertion loop of N2 plays a key role in its improved substrate preference. Furthermore, all the ancestors displayed remarkable thermostability, with N2 and N4 displaying superior thermal tolerance (Tm values are 54 and 59 °C, respectively, and their half-life times are longer than 90 h), positioning them as a promising candidate for industrial applications. This work introduces a promising enzymatic approach for T-2 degradation and lays a foundation for developing robust biocatalysts for the environmental and industrial bioremediation of mycotoxins.
