APPLIED BIOCHEMISTRY AND MICROBIOLOGY
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2024
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IF 1
Hu J.,Wu Y.,Kang L.,Liu Y.,Wu Y.,Han D.,Wang J.
Abstract Shiga toxin-producing Escherichia coli (STEC) is an important foodborne pathogen that seriously threats the public and animal health. The major virulence of STEC is Shiga toxin (Stx) which is encoded by Stx prophage. Stx prophage induction leads to the production of Stx. Our recent research has shown that dietary functional sugars can differently regulate Shiga toxin type 2 (Stx2) prophage induction. However, high-throughput assays are required to find more dietary inhibitors for Stx prophage induction. This study aims to establish the recA dual-luciferase reporter system for rapidly screening the functional sugars that can inhibit Stx prophage induction. Results showed that the recA dual-luciferase reporter plasmid was successfully constructed as confirmed by DNA sequencing. Established recA dual-luciferase reporter system showed similar screening results when compared with traditional temperate phage determination method (i.e., qPCR) and suggested that L-arabinose is a dietary functional Stx prophage induction inhibitor. Supplementation with L-arabinose in culture medium reduces Stx production in STEC isolated from fecal samples of diarrhea piglets. Collectively, the recA dual-luciferase reporter system is a promising tool for convenient and rapid screening of dietary Stx prophage induction inhibitor, especially suitable for large-scale screening experiments.
研究领域:
微生物学
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分子生物学
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食品安全
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生物技术
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产品关联
DOI
高影响因子
TALANTA
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2024
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IF 5.6
Kexin Ren,Mengxia Duan,Tingting Su,Dichen Ying,Shijia Wu,Zhouping Wang,Nuo Duan
Shiga toxin type II (Stx2), the major virulence component of enterohemorrhagic Escherichia coli , is strongly associated with the life-threatening hemolytic uremic syndrome thus posing a substantial risk to food safety and human health. In this work, a dual-mode aptasensor with colorimetric and surface-enhanced Raman scattering was developed for Stx2 specific detection based on noble metal nanoparticles and Raman reporter loaded metal-organic framework (Mn/Fe-MIL(53)@AuNSs-MBA). The Mn/Fe-MIL(53)@AuNSs could catalyze the H 2 O 2 -mediated oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB), thereby enabling visual detection. Meanwhile, the SERS signal from MBA can be enhanced by the decorated AuNSs. Under optimal conditions, a linear range of 0.05–500 ng/mL with limit of detection (LOD) of 26 pg/mL was achieved in colorimetric mode and a linear range of 5–1000 ng/mL with LOD of 0.82 ng/mL in SERS mode, in which the dual-mode results complement each other, widening the linear range, increasing the accuracy and reliability of the detection. The method was further applied to the detection of Stx2 in milk with average recovery of 101.1 %, demonstrating its superior potential for bacterial toxin monitoring.
研究领域:
生物传感
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食品科学
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分子诊断
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产品关联
DOI
PubMed
高影响因子
FOOD CONTROL
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2021
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IF 5.548
Shan Shan,Yanmei Huang,Zhaohong Huang,Zhonger Long,Chengwei Liu,Xuelong Zhao,Keyu Xing,Xiaoyue Xiao,Jintao Liu,Yunhong Huang,Weihua Lai,Daofeng Liu
Shiga toxin-producing Escherichia coli (STEC) is known as a kind of foodborne pathogens that can produce Shiga toxin type1, type 2, or both, encoded by stx1 and stx2 genes, respectively. Rapid and accurate detection of STEC and stx1 / stx2 subtyping assay in food and environment is essential for foodborne outbreak investigation. In this study, a method for the accurate and rapid subtyping of STEC single colony using asymmetric polymerase chain reaction (asPCR) combined with lateral flow immunoassay (LFIA) was established. AsPCR was conducted using biotinylated stx1 and digoxin-labeled stx2 primers to obtain several single stranded DNA amplicons labeled with biotin or/and digoxin. Subsequently, these amplicons were tagged with specific probes labeled with carboxylate-modified red polystyrene microspheres using sequential hybridization. Finally, STEC with different Shiga toxin gene types could be distinguished depending on the appearance of different test lines on an LFIA strip. Thus, the STEC single colony could be identified and subtyped accurately and conveniently using this method. This method showed high specificity. Twenty-four strains of STEC in milk were detected and subtyped using our method, which combines asPCR with LFIA.
研究领域:
微生物学
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分子生物学
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食品安全
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病原体检测
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产品关联
DOI
高影响因子
Gut Microbes
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2023
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IF 12.2
Jie Hu,Yifan Wu,Xingjian Zhou,Luyuan Kang,Shiyi Zhang,Yisi Liu,Yu Pi,Xilong Li,Junjun Wang,Dandan Han
The pathogenicity of Escherichia coli (E. coli) O157:H7 is predominantly associated with Shiga toxin 2 (Stx2) that poses a huge threat to human and animal intestinal health. Production of Stx2 requires expression of stx2 gene, which is located in the genome of lambdoid Stx2 prophage. Growing evidence has implicated that many commonly consumed foods participate in the regulation of prophage induction. In this study, we aimed to explore whether specific dietary functional sugars could inhibit Stx2 prophage induction in E. coli O157:H7, thereby preventing Stx2 production and promoting intestinal health. We demonstrated that Stx2 prophage induction in E. coli O157:H7 was strongly inhibited by L-arabinose both in vitro and in a mouse model. Mechanistically, L-arabinose at doses of 9, 12, or 15 mM diminished RecA protein levels, a master mediator of the SOS response, contributing to reduced Stx2-converting phage induction. L-Arabinose inhibited quorum sensing and oxidative stress response, which are known as positive regulators of the SOS response and subsequent Stx2 phage production. Furthermore, L-arabinose impaired E. coli O157:H7 arginine transport and metabolism that were involved in producing Stx2 phage. Collectively, our results suggest that L-arabinose may be exploited as a novel Stx2 prophage induction inhibitor against E. coli O157:H7 infection.
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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病理学
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产品关联
DOI
PubMed
高影响因子