Optimization of DNA Microsensor Arrays for Biological Detection

Abstract This paper describes the characterization and optimization of a reusable DNA microsensor array for rapid biological agent detection developed in previous publications. (Fig.1) [1–3] This MEMS based DNA sensor utilizes a standard three-electrode electrochemical cell configuration with novel micro fabricated structure design to minimize non-specific binding. The sensor module is easily to be adapted to various protocols and can be used for rapid detection of macromolecules (DNA, RNA) from targets such as uropathogenic Escherichia coli (E. coli) in urine and microorganisms causing otitis media (middle ear infection). Less than 105 E. coli cells can be detected from the urine sample of a patient with urine tract infection. The sensitivity is enhanced by appropriate sensor characterization and surface modification. The total detection time including sample preparation can be reduced to 25 minutes by using a POD conjugated oligonucleotide.

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Integration of a Gold-Specific Whole E. coli Cell Sensing and Adsorption Based on BioBrick

International Journal of Molecular Sciences ◽

10.3390/ijms19123741 ◽

2018 ◽

Vol 19 (12) ◽

pp. 3741

Author(s):

Li Yan ◽

Peiqing Sun ◽

Yun Xu ◽

Shanbo Zhang ◽

Wei Wei ◽

...

Keyword(s):

Heavy Metals ◽

Efficient Method ◽

Visual Detection ◽

Specific Binding ◽

Selective Detection ◽

Biological Detection ◽

Integration System ◽

Major Task ◽

E Coli ◽

Specific Binding Protein

Detection and recovery of heavy metals from environmental sources is a major task in environmental protection and governance. Based on previous research into cell-based visual detection and biological adsorption, we have developed a novel system combining these two functions by the BioBrick technique. The gold-specific sensory gol regulon was assembled on the gold-chaperone GolB (Gold-specific binding protein), which is responsible for selectively absorbing gold ions, and this led to an integration system with increased probe tolerance for gold. After being incorporated into E. coli, this system featured high-selective detection and recycling of gold ions among multi-metal ions from the environment. It serves as an efficient method for biological detection and recovery of various heavy metals. We have developed modular methods for cell-based detection and adsorption of heavy metals, and these offer a quick and convenient tool for development in this area.

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An Aggregation-Induced Emission Material Labeling Antigen-Based Lateral Flow Immunoassay Strip for Rapid Detection of Escherichia coli O157:H7

SLAS TECHNOLOGY Translating Life Sciences Innovation ◽

10.1177/2472630320981935 ◽

2021 ◽

pp. 247263032098193

Author(s):

Cheng Liu ◽

Shuiqin Fang ◽

Yachen Tian ◽

Youxue Wu ◽

Meijiao Wu ◽

...

Keyword(s):

Escherichia Coli ◽

Rapid Detection ◽

Foodborne Pathogen ◽

Test Strip ◽

Lateral Flow ◽

Detection Sensitivity ◽

Lateral Flow Immunoassay ◽

Escherichia Coli O157 ◽

Aggregation Induced Emission ◽

E Coli

Escherichia coli O157:H7 ( E. coli O157:H7) is a dangerous foodborne pathogen, mainly found in beef, milk, fruits, and their products, causing harm to human health or even death. Therefore, the detection of E. coli O157:H7 in food is particularly important. In this paper, we report a lateral flow immunoassay strip (LFIS) based on aggregation-induced emission (AIE) material labeling antigen as a fluorescent probe for the rapid detection of E. coli O157:H7. The detection sensitivity of the strip is 105 CFU/mL, which is 10 times higher than that of the colloidal gold test strip. This method has good specificity and stability and can be used to detect about 250 CFU of E. coli O157:H7 successfully in 25 g or 25 mL of beef, jelly, and milk. AIE-LFIS might be valuable in monitoring food pathogens for rapid detection.

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Lectin and E. coli Binding to Carbohydrate-Functionalized Oligo(ethylene glycol)-Based Microgels: Effect of Elastic Modulus, Crosslinker and Carbohydrate Density

Molecules ◽

10.3390/molecules26020263 ◽

2021 ◽

Vol 26 (2) ◽

pp. 263

Author(s):

Fabian Schröer ◽

Tanja J. Paul ◽

Dimitri Wilms ◽

Torben H. Saatkamp ◽

Nicholas Jäck ◽

...

Keyword(s):

Escherichia Coli ◽

Elastic Modulus ◽

Ethylene Glycol ◽

Concanavalin A ◽

Specific Binding ◽

Network Density ◽

Carbohydrate Binding ◽

E Coli ◽

Surface Recognition ◽

Strong Anchoring

The synthesis of carbohydrate-functionalized biocompatible poly(oligo(ethylene glycol) methacrylate microgels and the analysis of the specific binding to concanavalin A (ConA) and Escherichia coli (E. coli) is shown. By using different crosslinkers, the microgels’ size, density and elastic modulus were varied. Given similar mannose (Man) functionalization degrees, the softer microgels show increased ConA uptake, possibly due to increased ConA diffusion in the less dense microgel network. Furthermore, although the microgels did not form clusters with E. coli in solution, surfaces coated with mannose-functionalized microgels are shown to bind the bacteria whereas galactose (Gal) and unfunctionalized microgels show no binding. While ConA binding depends on the overall microgels’ density and Man functionalization degree, E. coli binding to microgels’ surfaces appears to be largely unresponsive to changes of these parameters, indicating a rather promiscuous surface recognition and sufficiently strong anchoring to few surface-exposed Man units. Overall, these results indicate that carbohydrate-functionalized biocompatible oligo(ethylene glycol)-based microgels are able to immobilize carbohydrate binding pathogens specifically and that the binding of free lectins can be controlled by the network density.

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Regulation of Expression of the TIR-Containing Protein C Gene of the Uropathogenic Escherichia coli Strain CFT073

Pathogens ◽

10.3390/pathogens10050549 ◽

2021 ◽

Vol 10 (5) ◽

pp. 549

Author(s):

Julia Ittensohn ◽

Jacqueline Hemberger ◽

Hannah Griffiths ◽

Maren Keller ◽

Simone Albrecht ◽

...

Keyword(s):

Escherichia Coli ◽

Protein C ◽

Interleukin 1 ◽

Coli Strain ◽

Uropathogenic Escherichia Coli ◽

Reporter Construct ◽

Regulation Of Expression ◽

E Coli ◽

Strain Cft073 ◽

Myeloid Differentiation Factor

The uropathogenic Escherichia coli strain CFT073 causes kidney abscesses in mice Toll/interleukin-1 receptor domain-containing protein C (TcpC) dependently and the corresponding gene is present in around 40% of E. coli isolates of pyelonephritis patients. It impairs the Toll-like receptor (TLR) signaling chain and the NACHT leucin-rich repeat PYD protein 3 inflammasome (NLRP3) by binding to TLR4 and myeloid differentiation factor 88 as well as to NLRP3 and caspase-1, respectively. Overexpression of the tcpC gene stopped replication of CFT073. Overexpression of several tcpC-truncation constructs revealed a transmembrane region, while its TIR domain induced filamentous bacteria. Based on these observations, we hypothesized that tcpC expression is presumably tightly controlled. We tested two putative promoters designated P1 and P2 located at 5′ of the gene c2397 and 5′ of the tcpC gene (c2398), respectively, which may form an operon. High pH and increasing glucose concentrations stimulated a P2 reporter construct that was considerably stronger than a P1 reporter construct, while increasing FeSO4 concentrations suppressed their activity. Human urine activated P2, demonstrating that tcpC might be induced in the urinary tract of infected patients. We conclude that P2, consisting of a 240 bp region 5′ of the tcpC gene, represents the major regulator of tcpC expression.

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A dynamic electrochemical cell sensor for selective capture, rapid detection and noninvasive release of tumor cells

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2020.129345 ◽

2021 ◽

Vol 330 ◽

pp. 129345

Author(s):

Xiaohua Tian ◽

Yonghai Feng ◽

Liang Yuan ◽

Yuqing Duan ◽

Lei Liu ◽

...

Keyword(s):

Tumor Cells ◽

Rapid Detection ◽

Electrochemical Cell

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Characterization of Anti-Bacterial Effect of the Two New Phages against Uropathogenic Escherichia coli

Viruses ◽

10.3390/v13071348 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1348

Author(s):

Lívia Slobodníková ◽

Barbora Markusková ◽

Michal Kajsík ◽

Michal Andrezál ◽

Marek Straka ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Therapeutic Potential ◽

Medical Intervention ◽

Uropathogenic Escherichia Coli ◽

E Coli ◽

Phage Cocktail ◽

Causative Agents ◽

Tract Infections

Urinary tract infections (UTIs) are among the events that most frequently need medical intervention. Uropathogenic Escherichia coli are frequently their causative agents and the infections are sometimes complicated by the presence of polyresistant nosocomial strains. Phage therapy is a tool that has good prospects for the treatment of these infections. In the present study, we isolated and characterized two bacteriophages with broad host specificity against a panel of local uropathogenic E. coli strains and combined them into a phage cocktail. According to genome sequencing, these phages were closely related and belonged to the Tequatrovirus genus. The newly isolated phages showed very good activity on a panel of local clinical E. coli strains from urinary tract infections. In the form of a two-phage cocktail, they were active on E. coli strains belonging to phylogroups B2 and D, with relatively lower activity in B1 and no response in phylogroup A. Our study is a preliminary step toward the establishment of a national phage bank containing local, well-characterized phages with therapeutic potential for patients in Slovakia.

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Enterobactin- and salmochelin-β-lactam conjugates induce cell morphologies consistent with inhibition of penicillin-binding proteins in uropathogenic Escherichia coli CFT073

Chemical Science ◽

10.1039/d0sc04337k ◽

2021 ◽

Author(s):

Artur Sargun ◽

Timothy C. Johnstone ◽

Hui Zhi ◽

Manuela Raffatellu ◽

Elizabeth M. Nolan

Keyword(s):

Escherichia Coli ◽

Binding Proteins ◽

Uropathogenic Escherichia Coli ◽

Penicillin Binding Proteins ◽

E Coli

Siderophore-β-lactam conjugates based on enterobactin and diglucosylated enterobactin enter the periplasm of uropathogenic E. coli CFT073 via the FepA and IroN transporters, and target penicillin-binding proteins.

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Viability and survival capability of quinolone-resistant uropathogenic Escherichia coli

Open Life Sciences ◽

10.2478/s11535-010-0070-9 ◽

2010 ◽

Vol 5 (6) ◽

pp. 827-830

Author(s):

Georgi Slavchev ◽

Nadya Markova

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Expression System ◽

Antibiotic Sensitivity ◽

Uropathogenic Escherichia Coli ◽

Resistant Bacteria ◽

E Coli ◽

Serum Bactericidal Assay ◽

Tract Infections ◽

Macrophage Killing

AbstractUropathogenic strains of E. coli isolated from urine of patients with urinary tract infections were tested for antibiotic sensitivity using bio-Merieux kits and ATB-UR 5 expression system. The virulence of strains was evaluated by serum bactericidal assay, macrophage “killing” and bacterial adhesive tests. Survival capability of strains was assessed under starvation in saline. The results showed that quinolone-resistant uropathogenic strains of E. coli exhibit significantly reduced adhesive potential but relatively high resistance to serum and macrophage bactericidity. In contrast to laboratory strains, the quinolone-resistant uropathogenic clinical isolate demonstrated increased viability during starvation in saline. Our study suggests that quinolone-resistant uropathogenic strains are highly adaptable clones of E. coli, which can exhibit compensatory viability potential under unfavorable conditions. The clinical occurrence of such phenotypes is likely to contribute to the survival, persistence and spread strategy of resistant bacteria.

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