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<b> </b>Attachment to the host gastric mucosa is a key step in <i>Helicobacter pylori </i>infection. Recently, a novel adhesin, HopQ, was shown to bind distinct host CEACAM proteins&#8212;an interaction that was found to be essential for the translocation of CagA, a key virulence factor of <i>H. pylori. </i>The HopQ&#8722;CEACAM1 co-crystal structure revealed a binding mode dependent on loops in HopQ that are clasped by disulfide bonds. In this study, we investigated the importance of these cysteine residues for CEACAM1 engagement by <i>H. pylori</i>. We observed a loss of CEACAM1 binding and CagA translocation upon disruption of the disulfide bond in loop CL1 (connecting C103 to C132 in HopQ). Deletion of the Dsb-like oxidoreductase HP0231 did not affect cell surface expression of HopQ or alter the interaction of <i>H. pylori</i> with target cells. Although HP0231 deletion was previously described to impede CagA translocation, our results indicate that this occurs through a HopQ-independent mechanism. Together, our results open up new avenues to therapeutically target the HopQ&#8722;CEACAM1 interaction and reduce the burden of pathogenic <i>H. pylori</i>.