AUTHOR=Cheng Yuchen , Zhang Jie , Ren Wenyi , Zhang Lili , Xu Xiaofeng 

TITLE=Response of a new rumen-derived Bacillus licheniformis to different carbon sources

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1238767

DOI=10.3389/fmicb.2023.1238767

ISSN=1664-302X

ABSTRACT=<sec><title>Introduction</title><p><italic>Bacillus licheniformis</italic> (<italic>B. licheniformis</italic>) is a microorganism with a wide range of probiotic properties and applications. Isolation and identification of novel strains is a major aspect of microbial research. Besides, different carbon sources have varying effects on <italic>B. licheniformis</italic> in regulating the microenvironment, and these mechanisms need to be investigated further.</p></sec><sec><title>Methods</title><p>In this study, we isolated and identified a new strain of <italic>B. licheniformis</italic> from bovine rumen fluid and named it <italic>B. licheniformis NXU98</italic>. The strain was treated with two distinct carbon sources—microcrystalline cellulose (MC) and cellobiose (CB). A combination of transcriptome and proteome analyses was used to investigate different carbon source effects.</p></sec><sec><title>Results</title><p>The results showed that <italic>B. licheniformis NXU98</italic> ABC transporter proteins, antibiotic synthesis, flagellar assembly, cellulase-related pathways, and proteins were significantly upregulated in the MC treatment compared to the CB treatment, and lactate metabolism was inhibited. In addition, we used MC as a distinct carbon source to enhance the antibacterial ability of <italic>B. licheniformis NXU98</italic>, to improve its disease resistance, and to regulate the rumen microenvironment.</p></sec><sec><title>Discussion</title><p>Our research provides a potential new probiotic for feed research and a theoretical basis for investigating the mechanisms by which bacteria respond to different carbon sources.</p></sec>