Expression of recombinant Clostridium difficile toxin A and B in Bacillus megaterium

Background: Major Clostridium difficile virulence factors are the exotoxins TcdA and TcdB.  Due to the large size and poor stability of the proteins, the active recombinant TcdA and TcdB have been difficult to produce. [...]

The enterotoxicity of Clostridium difficile toxins

This review considers the mechanisms of TcdA- and TcdB-induced enterotoxicity, and recent developments in this field.

Xingmin Sun profile:

University of South Florida:

Department of Molecular Medicine:

Current Projects

​​​C. difficile infection (CDI) has emerged as a significant public health threat worldwide.

Toxins are major virulent factors of C. difficile.

The Sun Lab ( focuses on the pathogenesis of C. difficile, host immune responses and development of novel preventive and therapeutic agents against CDI. We have established mouse and hamster models of CDI to support basic and applied research on the pathogenesis of C. difficile. We also use multidisciplinary approaches in our research, including molecular biology/microbiology, immunology, cell biology, protein engineering, genome sequencing and bioinformatics, flow cytometry and nano-particle delivery.

Relevant Reading

Clostridioides difficile  (Clostridium difficile)


Research Interests

1) The roles of innate immunity and intestinal microbiome in the pathogenesis of CDI

2) Physiology, virulence and pathogenesis mechanisms of C. difficile 

3) Development of novel therapeutic /preventive agents including vaccines and antimicrobials against C. difficile

4) Antibiotic resistance mechanisms of C. difficile

5) Signaling pathways of pro-inflammatory mediators and CDI