Effect of deoxymannojirimycin and Brefeldin A onYersinia pseudotuberculosisinvasin–eukaryotic cell interaction

The cell surface receptors of theYersinia pseudotuberculosisinvasin protein are theα_3–6β₁integrins. Invasin and the extracellular matrix protein fibronectin bind to the same or closely located sites onα₅β₁integrin, although invasin bind with a much greater affinity. Invasin-integrin interaction promotes bacterial penetration into eukaryotic cells. Binding of fibronectin to its integrin receptor seems to be dependent on terminal oligosaccharides processing. In this paper, we have examined the effect of 1-deoxymannojirimycin (dMNJ), an inhibitor of Golgiα-mannosidases involved in processing of N-glycan precursors, and of Brefeldin A (BFA), a natural product of fungi which has profound effects on the structure and function of the Golgi apparatus, on invasin–cell interaction. We found that unlike fibronectin, the interaction of invasin with cells was resistance to dMNJ. However, preincubating cells with BFA caused a dose dependent inhibition of invasin-mediated cell entry, while cell invasion bySalmonella typhimuriumwas not affected.