TY - JOUR
T1 - Transcriptional response and enhanced intestinal adhesion ability of lactobacillus rhamnosus GG after acid stress
AU - Bang, Miseon
AU - Yong, Cheng Chung
AU - Ko, Hyeok Jin
AU - Choi, In-Geol
AU - Oh, Sejong
PY - 2018/10/1
Y1 - 2018/10/1
N2 - Lactobacillus rhamnosus GG (LGG) is a probiotic commonly used in fermented dairy products. In this study, RNA-sequencing was performed to unravel the effects of acid stress on LGG. The transcriptomic data revealed that the exposure of LGG to acid at pH 4.5 (resembling the final pH of fermented dairy products) for 1 h or 24 h provoked a stringent-type transcriptomic response wherein stress response-and glycolysis-related genes were upregulated, whereas genes involved in gluconeogenesis, amino acid metabolism, and nucleotide metabolism were suppressed. Notably, the pilus-specific adhesion genes, spaC, and spaF were significantly upregulated upon exposure to acid-stress. The transcriptomic results were further confirmed via quantitative polymerase chain reaction analysis. Moreover, acid-stressed LGG demonstrated an enhanced mucin-binding ability in vitro, with 1 log more LGG cells (p < 0.05) bound to a mucin layer in a 96-well culture plate as compared to the control. The enhanced intestinal binding ability of acid-stressed LGG was confirmed in an animal study, wherein significantly more viable LGG cells (≥ 2 log CFU/g) were observed in the ileum, caecum, and colon of acid-stressed LGG-treated mice as compared with a non-acid-stressed LGG-treated control group. To our knowledge, this is the first report showing that acid stress enhanced the intestine-binding ability of LGG through the induction of pili-related genes.
AB - Lactobacillus rhamnosus GG (LGG) is a probiotic commonly used in fermented dairy products. In this study, RNA-sequencing was performed to unravel the effects of acid stress on LGG. The transcriptomic data revealed that the exposure of LGG to acid at pH 4.5 (resembling the final pH of fermented dairy products) for 1 h or 24 h provoked a stringent-type transcriptomic response wherein stress response-and glycolysis-related genes were upregulated, whereas genes involved in gluconeogenesis, amino acid metabolism, and nucleotide metabolism were suppressed. Notably, the pilus-specific adhesion genes, spaC, and spaF were significantly upregulated upon exposure to acid-stress. The transcriptomic results were further confirmed via quantitative polymerase chain reaction analysis. Moreover, acid-stressed LGG demonstrated an enhanced mucin-binding ability in vitro, with 1 log more LGG cells (p < 0.05) bound to a mucin layer in a 96-well culture plate as compared to the control. The enhanced intestinal binding ability of acid-stressed LGG was confirmed in an animal study, wherein significantly more viable LGG cells (≥ 2 log CFU/g) were observed in the ileum, caecum, and colon of acid-stressed LGG-treated mice as compared with a non-acid-stressed LGG-treated control group. To our knowledge, this is the first report showing that acid stress enhanced the intestine-binding ability of LGG through the induction of pili-related genes.
KW - Adhesion
KW - Lactobacillus
KW - Microbial physiology
KW - Probiotics
KW - Stress response
KW - Transcriptomics
UR - http://www.scopus.com/inward/record.url?scp=85065752277&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85065752277&partnerID=8YFLogxK
U2 - 10.4014/jmb.1807.07033
DO - 10.4014/jmb.1807.07033
M3 - Article
C2 - 30196592
AN - SCOPUS:85065752277
VL - 28
SP - 1604
EP - 1613
JO - Journal of Microbiology and Biotechnology
JF - Journal of Microbiology and Biotechnology
SN - 1017-7825
IS - 10
ER -