Journal of Functional Foods
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2025
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IF 4
Zhaoxi Deng,Yanfei Ma,Kangwei Hou,Jinyan Dai,Yifan Zhong,Yingying Mao,Jinzhi Zhang,Haifeng Wang
Quorum sensing (QS) is an essential pathway for bacterial communication through autoinducers (AIs). The luxS gene involved in QS has been proven to regulate different behavior of Lactobacillus rhamnosus GG (LGG), whereas it is unclear whether the AI-2/LuxS system have beneficial effects the host by regulating LGG. Our aim was to investigate whether luxS mutation affects the ability of LGG to maintain intestinal microbiota homeostasis, intestinal barrier integrity and inflammatory immune responses in mice infected with Escherichia coli ( E. coli ). This study showed that both wild-type (WT) and luxS mutant (ΔluxS) of LGG can alleviate changes in the microbiota caused by E. coli by down-regulating the relative abundance of Parasturtella . Supplementation with WT and ΔluxS increased the CD4 + /CD8 + ratio in spleen, improved goblet cell numbers and enhanced Muc 2 secretion. Moreover, WT and ΔluxS decreases proinflammatory mediator levels by inhibiting MAPK and NF-κB signal transduction.
研究领域:
微生物学
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免疫学
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分子生物学
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产品关联
DOI
高影响因子
Foods
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2022
·Vol. 11
·期 9
·1203
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IF 5.561
Jiao Shi,Shu-Fang Li,Kun Feng,Shuang-Yan Han,Teng-Gen Hu,Hong Wu
For improving probiotics’ survivability under harsh conditions, this study usedLactiplantibacillus plantarumGIM1.648 as a model microorganism to investigate its ability to produce biofilms on electrospun ethyl cellulose nanofiber mats. SEM observations confirmed that biofilm was successfully formed on the nanofibers, with the latter being an excellent scaffold material. The optimal cultivation conditions for biofilm formation were MRS medium without Tween 80, a culture time of 36 h, a temperature of 30 °C, a pH of 6.5, and an inoculum concentration of 1% (v/v). The sessile cells in the biofilm exhibited improved gastrointestinal and thermal tolerance compared to the planktonic cells. Additionally, the RT-qPCR assay indicated that theluxSgene played a crucial role in biofilm formation, with its relative expression level being 8.7-fold higher compared to the planktonic cells. In conclusion, biofilm formation on electrospun nanofiber mat has great potential for improving the viability of probiotic cells under harsh conditions.Keywords:electrospun nanofiber mat;biofilm;probiotics;viability;luxSgene
研究领域:
微生物学
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食品科学
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材料科学
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DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2025
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IF 9
Yuan Li,Danchen Zhu,Linmeng Hong,Jixiang Dai,Lijun Wu
This study systematically investigated the effect of interfering with autoinducer-2 (AI-2) signaling system on controlling initial fouling attachment and irreversible components. Exposure of bacteria to the inhibitor significantly reduced the expression of the luxS gene, which resulted in a 37.3% reduction of AI-2 signaling molecule synthesis. Expression of flagellin and kinesin, which determine bacteria adhesion properties, and virulence genes was significantly down-regulated. AI-2 quorum quenching (QQ) significantly suppressed the initial biofilm growth and inhibition efficiency was positively correlated with bacteria concentration. Extracellular polymeric substances accumulation decreased by 40.8% in QQ experiment relative to the control, thus mitigating the flux decline. Polysaccharides, which constitute irreversible components, were significantly reduced by 69.3% with presence of inhibitor. AI-2 QQ altered protein and peptide structure of fouling layer, which converted irreversible fouling into reversible fouling. These findings contributed to the understanding of QQ susceptibility to initial fouling, providing a theoretical basis for engineering applications.
研究领域:
微生物学
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环境工程
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Food Bioscience
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2024
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IF 4.8
Xueqi Lu,Mengying Sun,Yuqing Chen,Dashuai He,Yanfeng Tuo,Guangqing Mu,Yinglong Song
Fermented milk is a typically product of co-fermentation by a variety of lactic acid bacteria (LAB). Quorum sensing (QS), as an intercellular communication mechanism of bacteria, may serve as a key factor influencing the quality of fermented milk. In this study, the fermentation performance of Lactobacillus delbrueckii subsp . bulgaricus DPUL-F36 were evaluated after supplementation with auto-inducer-2 (AI-2). The protein-protein interaction network (PPIN) was used to retrieve the interactions between QS genes and four major metabolic pathway genes. The expression of luxS gene in DPUL-F36 may affect amino acid metabolism, carbohydrate metabolism and cell wall formation. The key differential metabolites were identified by metabolomics analysis. A variety of amino acids including L-Glutamic, L-Tryptophan, L-Threonine, L-Histidine and L-Glutamine were found to be up-regulated in response to the addition of AI-2. Malic acid and succinate gradually accumulate in the tricarboxylic acid cycle. The consumption of citric acid increased with the fermentation process. In terms of rheological and texture characteristics of fermented milk, addition of AI-2 could effectively improve its shear stress resistance, firmness and index of viscosity. Our research provided a theoretical basis for improving the fermentation performance of DPUL-F36 strains, and support for the screening of excellent composite starter culture.
研究领域:
微生物学
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食品科学
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分子生物学
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生物技术
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DOI
高影响因子
危险品化学品经营许可证（带存储）