Plant germplasm resources with natural resistance against globally important toxigenic Fusarium are inadequate. CWP2, a Fusarium genus-specific antibody, confers durable resistance to different Fusarium pathogens that infect cereals and other crops, producing mycotoxins. However, the nature of the CWP2 target is not known. Thus, investigation of the gene coding for the CWP2 antibody target will likely provide critical insights into the mechanism underlying the resistance mediated by this disease-resistance antibody. Immunoblots and mass spectrometry analysis of two-dimensional electrophoresis gels containing cell wall proteins from Fusarium graminearum (Fg) revealed that a glyoxal oxidase (GLX) is the CWP2 antigen. Cellular localization studies showed that GLX is localized to the plasma membrane. This GLX efficiently catalyzes hydrogen peroxide production; this enzymatic activity was specifically inhibited by the CWP2 antibody. GLX-deletion strains of Fg, F. verticillioides (Fv) and F. oxysporum had significantly reduced virulence on plants. The GLX-deletion Fg and Fv strains had markedly reduced mycotoxin accumulation, and the expression of key genes in mycotoxin metabolism was downregulated. This study reveals a single gene-encoded and highly conserved cellular surface antigen that is specifically recognized by the disease-resistance antibody CWP2 and regulates both virulence and mycotoxin biosynthesis in Fusarium species.

A kind of biomaterial with antibacterial and mechanical properties was prepared using gelatin (GE) as a raw material. GE was modified by antibacterial epoxy quaternary ammonium salt (QAS) and then cross-linked with tannic acid (TA). Analysis of the Fourier transform infrared spectroscopy (FTIR) results showed that the cationic group was grafted onto GE by reaction of the amino of GE with the epoxy of QAS, and the cross-linking occurred between the amino of GE and the active groups of TA under alkaline conditions. The cross-linking degree was determined by the fluorescence method via a derivative reaction of fluorescamin. The influence of the cross-linking degree on the physical and chemical properties of the GE film was studied by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and mechanical testing. The results showed that the modified GE film formed a compact cross-linking structure, and its thermostability and mechanical properties were improved with increasing cross-linking degree. The in vitro antibacterial rate of the cross-linked cationic GE film to Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) reached 95.83% and 100% respectively, and the in vitro cell relative growth rate (RGR) of HeLa cells cultured in the extracted leachate of the cross-linked cationic GE film exceeded 85%, which illustrated that the modified GE film had excellent antibacterial activity and biocompatibility.

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