Screening and Molecular Marking of Highly Adhesive Pediococcus pentosaceus and the Characteristics of Their Surface Hydrophobicities and Autoaggregation Abilities

Abstract:

Seven strains of Pediococcus pentosaceus were isolated and identified from the fermented stinky tofu brine using methods of conventional bacteria isolation combined with physiological and biochemical test and 16S rDNA sequencing identification. The specific fingerprint for each strain was developed by the random amplified polymorphic DNA(RAPD) technique. The adhesive ability of the strain and the correlation of phenotypic characteristics of strain adhesion and genotype，surface hydrophobicity，and aggregation ability were studied using Caco-2 cell and intestinal mucus protein as in vitro model. Results showed that six different fingerprint patterns were found in the seven Pediococcus pentosaceus strains，among them，the A5 subtype of strains(F28-8 and Y27-4) showed the strongest adhesion to the Caco-2 cells and intestinal mucus. Furthermore，these two strains also exhibited highly hydrophobic(the hydrophobicity rate > 90%) and higher aggregation ability(the aggregation rate at 2 h > 5%). Correlation analysis results showed that the surface hydrophobicity and aggregation ability of Pediococcus pentosaceus were positively related to the adhesive ability to the Caco-2 cell significantly(r=0.900 and 0.792，P<0.05)，but they were not significantly correlated to the adhesive ability to the intestinal mucus(r = 0.426 and 0.700，P>0.05). The results of this study provide the basis for establishing techniques of rapid screening highly adhesive Pediococcus pentosaceus strains and their colonization and distribution in vivo.