Effects of Sub-Lethal High Pressure Homogenization Treatment on the Adhesion Mechanisms and Stress Response Genes in Lactobacillus acidophilus 08

Giacomo Braschi; Margherita D'Alessandro; Davide Gottardi; Lorenzo Siroli; Francesca Patrignani; Rosalba Lanciotti

doi:10.3389/fmicb.2021.651711

Effects of Sub-Lethal High Pressure Homogenization Treatment on the Adhesion Mechanisms and Stress Response Genes in Lactobacillus acidophilus 08

Front Microbiol. 2021 May 28:12:651711. doi: 10.3389/fmicb.2021.651711. eCollection 2021.

Authors

Giacomo Braschi¹, Margherita D'Alessandro¹, Davide Gottardi¹, Lorenzo Siroli^{1

2}, Francesca Patrignani^{1

2}, Rosalba Lanciotti^{1

2}

Affiliations

¹ Department of Agricultural and Food Sciences, University of Bologna, Cesena, Italy.
² Interdepartmental Center for Industrial Agri-Food Research, University of Bologna, Cesena, Italy.

Abstract

Cell surface hydrophobicity (CSH) and adhesion are very important phenotypical traits for probiotics that confer them a competitive advantage for the resilience in the human gastrointestinal tract. This study was aimed to understand the effects over time of a 50 MPa hyperbaric treatment on the surface properties of Lactobacillus acidophilus 08 including CSH, autoaggregation, and in vitro adhesion (mucin layer and Caco-2 cells). Moreover, a link between the hurdle applied and the expression of genes involved in the general stress response (groEL and clpP) and adhesion processes (efTu and slpA) was evaluated. High pressure homogenization (HPH) at 50 MPa significantly increased the CSH percentage (H%), autoaggregation and in vitro adhesion on mucin of L. acidophilus 08 cells compared with the untreated cells. Moreover, the hyperbaric hurdle induced an upregulation of the stress response genes groEL and ef-TU together with a down regulation of the clpP and S-layer slpA genes. Looking at the protein profile, HPH-treatment showed an increase in the number or intensity of protein bands at high and low molecular weights.

Keywords: Lactobacillus acidophilus 08; adhesion; cell surface hydrophobicity; chaperonin; high pressure homogenization; moonlight protein; probiotics; stress response.