APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
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2021
·Vol. 105
·期 7
·2841-2854
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IF 4.813
Zhou Gang,Wang Ying-si,Peng Hong,Li Su-juan,Sun Ting-li,Shen Peng-fei,Xie Xiao-bao,Shi Qing-shan
Abstract The genus Citrobacter is commonly found in environmental and industrial settings, some members of which have been used for bioremediation of heavy metals owing to the absorption ability of their biofilms. Although our previous studies have found that the outer membrane protein A (OmpA) contributes to the process of Citrobacter werkmanii biofilm formation, the underlying mechanisms remain elusive. Therefore, we deleted ompA from the genome of C. werkmanii and investigated its phenotypes in comparison to the wild type strain (WT) and the complementary strain using biochemical and molecular techniques including RNA-Seq. Our results demonstrated that the deletion of ompA led to an increase in biofilm formation on both polystyrene and glass surfaces due to upregulation of some biofilm formation related genes. Meanwhile, swimming ability, which is mediated by activation of flagellar assembly genes, was increased on semi-solid plates in the ∆ompA strain when compared with WT. Additionally, inactivation of ompA also caused increased 1,2-benzisothiazolin-3-one (BIT) resistance, differential responses to Ca 2+ stress, curli protein expression and cellulose production. Finally, ∆ompA caused differential expression of a total of 1470 genes when compared with WT, of which 146 were upregulated and 1324 were downregulated. These genes were classified into different Gene Ontology (GO) and KEGG pathways. In summary, ompA in C. werkmanii contributes to a variety of biological functions and may act as a target site to modulate biofilm formation. Key points
• ompA is a negative regulator for biofilm formation by C. werkmanii.
• ompA inhibits swimming motility of C. werkmanii.
• ompA deletion causes different expression profiles in C. werkmanii.
研究领域:
微生物学
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分子生物学
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环境科学
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PubMed
高影响因子
JOURNAL OF BACTERIOLOGY
·
2023
·Vol. 205
·期 8
·
IF 3.2
Meng-na Zhang,Xiao-ou Zhao,Qi Cui,Dao-mi Zhu,Muhammad Asif Wisal,Han-dong Yu,Ling-cong Kong,Hong-xia Ma
The development of novel antibiotic adjuvants is imminent because of the frequent emergence of resistance in Gram-negative bacteria, which severely restricts the efficiency and longevity of commonly used clinical antibiotics. It is reported that famotidine, a clinical inhibitor of gastric acid secretion, enhances the antibacterial activity of rifamycin antibiotics, especially rifampicin, against Gram-negative bacteria and reverses drug resistance. Studies have shown that famotidine disrupts the cell membrane of Acinetobacter baumannii and inhibits the expression of the outer membrane protein ompA gene, while causing a dissipation of the plasma membrane potential, compensatively upregulating the pH gradient and ultimately increasing the accumulation of reactive oxygen species by leading to increased bacterial mortality. In addition, famotidine also inhibited the efflux pump activity and the biofilm formation of A. baumannii. In the Galleria mellonella and mouse infection models, the combination of famotidine and rifampicin increased the survival rate of infected animals and decreased the bacterial load in mouse organs. In conclusion, famotidine has the potential to be a novel rifampicin adjuvant, providing a new option for the treatment of clinical Gram-negative bacterial infections.IMPORTANCE In this study, famotidine was discovered for the first time to have potential as an antibiotic adjuvant, enhancing the antibacterial activity of rifamycin antibiotics against A. baumannii and overcoming the limitations of drug therapy. With the discovery of novel applications for the guanidine-containing medication famotidine, the viability of screening prospective antibiotic adjuvants from guanidine-based molecules was further explored. In addition, famotidine exerts activity by affecting the OmpA protein of the cell membrane, indicating that this protein might be used as a therapeutic drug target to treat A. baumannii infections.
研究领域:
微生物学
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药理学
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传染病
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抗菌素耐药性
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PubMed
高影响因子
SENSORS
·
2023
·Vol. 23
·期 9
·4396
·
IF 3.9
Hongyan Zhang,Guiqing Xu,Yuming Chen,Xu Li,Shaopeng Wang,Feihao Jiang,Pengyang Zhan,Chuanfu Lu,Xiaodong Cao,Yongkang Ye,Yunlai Tao
The present work developed an electrochemical genosensor for the detection of virulence outer membrane protein A (ompA,tDNA) gene ofCronobacter sakazakii(C. sakazakii) by exploiting the excellent glucose-oxidase-mimicking activity of copper Metal-organic frameworks (Cu-MOF) doped with gold nanoparticle (AuNPs). The signal nanotags of signal probes (sDNA) that biofunctionalized[email protected]([email protected]) were designed using an Au-S bond. The biosensor was prepared by immobilization capture probes (cDNA) onto an electrodeposited AuNPs-modified glassy carbon electrode (GCE).[email protected]was introduced onto the surface of the GCE via a hybridization reaction between cDNA and tDNA, as well as tDNA and sDNA. Due to the enhanced oxidase-mimicking activity of[email protected]to glucose, the biosensor gave a linear range of 1.0 × 10−15to 1.0 × 10−9mol L−1to tDNA with a detection limit (LOD) of 0.42 fmol L−1under optimized conditions using differential pulse voltammetry measurement (DPV). It can be applied in the direct detection ofompAgene segments in total DNA extracts fromC. sakazakiiwith a broad linear range of 5.4−5.4 × 105CFU mL−1and a LOD of 0.35 CFU mL−1. The biosensor showed good selectivity, fabricating reproducibility and storage stability, and can be used for the detection ofompAgene segments in real samples with recovery between 87.5% and 107.3%.Keywords:electrochemical biosensor;C. sakazakii;gold-nanoparticle-doped copper Metal-organic frameworks;ompAgene;glucose-oxidase-mimicking activity
研究领域:
生物化学
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分析化学
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纳米技术
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微生物学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2022
·
IF 9.231
Xiaodong Cao,Minli Liu,Jie Lu,Hongge Lv,Jinzhe Han,Shudong He,Yongkang Ye,Xiangyang Chen,Zhaojun Wei,Haisong Zheng
This work presented an electrochemical biosensor for the detection of virulence outer membrane protein A ( ompA ) gene of Cronobacter sakazakii ( C. sakazakii ), which was based on the mimic peroxidase activity of boron doped quantum dots-Au nanoparticles (BQDs-AuNPs) and a signal amplification strategy of exonuclease III (Exo III)-assisted target-recycling (EATR). The electrochemical signal was come from the electrochemical reduction of H 2 O 2 by BQDs-AuNPs nanozyme. Due to the enhanced peroxidase-mimic electrocatalytic efficiency of BQDs-AuNPs and the EATR strategy, the biosensor showed a broad linear range (1.0 × 10 -15 – 1.0 × 10 -8 mol L -1 ) and a low limit of detection (LOD, 4.0 × 10 -17 mol L -1 ). The constructed biosensor could also be applied in direct detection of extracted DNA from C. sakazakii . A good linear relationship (7.8 – 7.8 × 10 6 CFU mL −1 ) between the logarithm concentration of C. sakazakii and electrochemical signal was obtained with a LOD of 2.6 CFU mL −1 . The biosensor was applied in the detection of impA gene segments in contaminated infant formula with recoveries ranged in 83.4 – 108.2%.
研究领域:
生物化学
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纳米技术
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分析化学
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微生物学
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食品科学
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PubMed
高影响因子
Cell Reports Medicine
·
2026
·
IF 14
Junhua Xie,Xi-jian Dai,Qiqiong Li,Wanyu Zhang,Xinke Nie,Haihua Ji,Xinyang Chen,Yuchen Wang,Jing Feng,Zhipeng Li,Qiong Liu,Jianxin Ye,Guangzhi Zhang,Shaoping Nie
Gut microbiota dysbiosis is a driving factor in Alzheimer’s disease (AD), yet the mechanisms behind remain elusive. Emerging evidence highlights that outer membrane vesicles (OMVs) are critical mediators of microbiota-host communication. Here, we observed a reduction in a gut probiotic Escherichia coli Nissle 1917 (EcN)-like strain in AD patients, and its levels are positively associated with cognitive ability. The EcN OMVs containing outer membrane protein A (OmpA) translocate to the brain, reshaping the dysregulated immune network. Specifically, EcN OMVs are internalized by glia and neurons, suppressing glial hyperactivation and restoring synaptic function, thereby reducing Aβ deposition and cognitive deficits. The results further show that OmpA plays an important role in vesicle trafficking and inflammatory pathways and may be the key regulator of inflammatory mediators in EcN OMVs, modulating astrocyte-microglia-neuron interactions and functionality. This work discloses the substantial therapeutic potential of the probiotic and its secreted OMVs in intervention and treatment of neurological disorders.
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PubMed
高影响因子
BIOTECHNOLOGY AND BIOPROCESS ENGINEERING
·
2013
·Vol. 17
·期 6
·1128-1134
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IF 1.277
Li Bin,Wang Lei,Su Lingqia,Chen Sheng,Li Zhaofeng,Chen Jian,Wu Jing
OmpA signal peptide mediated cgt gene from Paenibacillus macerans JFB05-01 was cloned and expressed in E. coli BL21 (DE3). The effects of glycine and Triton X-100 on extracellular production of α-cyclodextrin glycosyltransferase (α-CGTase) were investigated. When supplemented with Gly or Triton X-100 to the culture media individually, the secreted extracellular enzyme reached 32 or 33 U/mL at 48 h of cultivation, respectively. When supplemented with Gly and Triton X-100 together, the extracellular α-CGTase activity reached 48 U/mL after 48 h cultivation, which was 20-fold of the control group without any additives. Analysis of membrane permeability demonstrated that addition of glycine and Triton X-100 enhanced the permeability of both outer and inner membrane. The potential mechanism of the enhanced protein secretion was discussed.
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高影响因子
危险品化学品经营许可证（带存储）