FUNCTIONAL CHARACTERIZATION OF PROBIOTIC SURFACE LAYER PROTEIN OF LACTOBACILLUS ACIDOPHILUS ATCC 4356

FINA MARTIN, JOAQUINA; RUZAL, SANDRA M.; BARQUERO ANDREA

Salta

Congreso; Joint LV Annual SAIB Meeting and XIV PABMB Congress; 2019

SAIB

The surface layer protein (Slp) of Lactobacillus acidophilus ATCC 4356 is non-covalently bound to the outmost bacterial cell wall but its involvement in the adherence of bacteria to host cells remain unknown. We have previously described that the SlpA presents lectin-like activity located in the carboxyl-terminal portion of the protein, interacting with prokaryotic (peptidoglycan and lipoteichoic acids) and with eukaryotic (mucin) macromolecules, as well as with viruses, bacteria, yeast and blood cells. While the amino-terminal portion is responsible for self-assembly and interaction with extracellular matrix (ECM) proteins, fibronectin and collagen. Here, we study the interaction of purified SlpA with intestinal epithelial cells and its ability to modulate the infection of herpes simplex type 1 virus (HSV-1). First, we observed that SlpA bound to the surface of Caco-2/TC7 and HT29 intestinal cells using indirect immunofluorescence (IFI) assay with Slp-specific antibodies. Then, we found that SlpA had no antiviral action against HSV-1 multiplication in HT29 cells. Moreover, we determined that the purified protein was able to protect HSV-1 from heat inactivation, probably through its carbohydrate recognition domains since this effect was inhibited by addition of D-mannose. In summary, our results suggested that SlpA mediates the adherence of bacteria to intestinal cells and interacts with viral glycosylated components.