AUTHOR=Liu Zhenzhen , Zhao Xiao , Bangash Hina Iqbal 

TITLE=Expression of stress responsive genes enables Limosilactobacillus reuteri to cross-protection against acid, bile salt, and freeze-drying

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1437803

DOI=10.3389/fmicb.2024.1437803

ISSN=1664-302X

ABSTRACT=<sec><title>Introduction</title><p><italic>Limosilactobacillus reuteri</italic> effectively colonizing the gut, secretes antimicrobial compounds and strengthens immune system function. Considering these health benefits, increasing its stress assessments efficiency could improve its commercial viability.</p></sec><sec><title>Methods</title><p>In this work, the resistance of <italic>L. reuteri</italic> FP41 to acid, bile salts, and freeze-drying was examined.</p></sec><sec><title>Results</title><p>The findings showed that strain FP41 demonstrated a strong resistance to acid/bile salt stresses. The transcriptome revealed a significant up-regulation of various stress response genes, including those related to membrane integrity, glutamine metabolism, OsmC family protein, ABC transporters, and chaperonin. Subsequent research demonstrated that overexpression of three stress response-specific proteins, including glutamate decarboxylase GatD, osmotically induced bacterial protein OsmC, and membrane protein component CsbD, significantly increased the survival rate of <italic>L. reuteri</italic> Z204 under acid/bile salts stress. Notably, overexpression of the OsmC, CsbD, and GatD proteins also enhanced the survival of <italic>L. reuteri</italic> after freeze-drying.</p></sec><sec><title>Discussion</title><p>The development of a unique cross-protection method is highlighted in this study, that might significantly increase cellular resistance to acid, bile salts, and cold stresses. This finding could significantly impact the way that <italic>L. reuteri</italic> is employed in industrial manufacturing processes.</p></sec>