Aims: This work aims to investigate the binding capability of certain domains at N terminus of the protein NP_785232 of Lactobacillus plantarum to Caco-2 cells and to test the usage of affinity chromatography to isolate the human mucus component that interacts with them.
Methods and Results: Recombinant proteins containing the first and both the first and second domains at N terminus of NP_785232 fused to a His tag were constructed and used to bind the Caco-2 cells. The interacting molecule from human mucus was isolated by affinity chromatography through immobilizing the recombinant proteins onto a Sepharose matrix. It was found both recombinant proteins could block the adhesion of Lact. plantarum to Caco-2 cells and bind to a human mucus component.
Conclusions: The first and both the first and second domains at N terminus of the protein NP_785232 have the capability to adhere Caco-2 cells and by affinity chromatography, an interacting UV-absorbing component from human mucus was isolated.
Significance and Impact of the Study: The protein domains characterized in this study may be displayed on probiotics to promote adhesion, and further characterization of the human mucus component might be helpful to identify host factors required for prolonging probiotics persistence in the gastrointestinal tract.