ZBiotech’s 100 glycan microarray helps researchers identify the carbohydrate substrates of transferase toxin 2 of C. difficile.

Hospital infections associated with C. difficile are one of the leading death causes in the United States. C. difficile (Clostridioides difficile) is a bacterium that causes gastroenteritis, diarrhea, and colitis. C. difficile infection usually happens after the host’s microbiome becomes weakened. The first step of the infection is the release of toxin A, toxin B, and the C. difficile transferase toxin 2 (CDT2). Recently, it has been suggested that CDT2 increases the severity of the infection in some problematic clinical strains. Therefore, Anderson and colleagues investigated the function and structure of CDT2 in more depth and found that CDT2 can transit from a prepore to a β-barrel pore. Structural analysis also revealed a novel glycan-binding domain within CDT2, which involves interactions with host cells. Indeed, a sequence search and the distance matrix alignment suggested this domain can bind with galactose. This previously unknown discrete domain of CDT2 is called D3′.

The scientists validated these findings by using our 100 Glycan Microarray. They found that D3′ binds with L-fucose, D-fucose, L-rhamnose, chitobiose, chitotriose, and lacto-N-tetraose. This led to the conclusion that CDT2 binds carbohydrate receptors on host cells rather than the previously thought protein receptors.

Our glycan microarrays can help researchers study the binding properties of potential carbohydrate-binding domains in highly infective pathogens, possibly helping to identify novel binding partners on the host cells.