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Pathogenic Yersinia resist uptake by eukaryotic cells by a mechanism involving the virulence protein YopH, a protein tyrosine phosphatase. We show that p130^Cas and FAK are phosphorylated and recruited to peripheral focal complexes during bacterial uptake in HeLa cells. The inactive form of YopH interacts with the tyrosine phosphorylated forms of FAK and p130^Cas and co-localizes with these proteins in focal adhesions. On the other hand, the presence of active YopH results in inhibition of uptake, dephosphorylation of p130^Cas and FAK, and disruption of peripheral focal complexes. We suggest that p130^Cas and FAK are substrates for YopH and that the dephosphorylation of these proteins impairs the uptake of Yersinia pseudotuberculosis into HeLa cells.