Barcoded microbial system for high-resolution object provenance

Science ◽  
2020 ◽  
Vol 368 (6495) ◽  
pp. 1135-1140 ◽  
Author(s):  
Jason Qian ◽  
Zhi-xiang Lu ◽  
Christopher P. Mancuso ◽  
Han-Ying Jhuang ◽  
Rocío del Carmen Barajas-Ornelas ◽  
...  
Keyword(s):  
Food Safety ◽  
Nucleic Acid ◽  
High Resolution ◽  
Human Health ◽  
Nucleic Acid Detection ◽  
Single Spore ◽  
Detection Assay ◽  
Wide Range ◽  
Fundamental Challenge ◽  
Microbial System

Determining where an object has been is a fundamental challenge for human health, commerce, and food safety. Location-specific microbes in principle offer a cheap and sensitive way to determine object provenance. We created a synthetic, scalable microbial spore system that identifies object provenance in under 1 hour at meter-scale resolution and near single-spore sensitivity and can be safely introduced into and recovered from the environment. This system solves the key challenges in object provenance: persistence in the environment, scalability, rapid and facile decoding, and biocontainment. Our system is compatible with SHERLOCK, a Cas13a RNA-guided nucleic acid detection assay, facilitating its implementation in a wide range of applications.

Forensic microbial system for high-resolution object provenance

2020 ◽  
Author(s):  
Jason Qian ◽  
Zhi-xiang Lu ◽  
Christopher P. Mancuso ◽  
Han-Ying Jhuang ◽  
Rocío del Carmen Barajas-Ornelas ◽  
...  
Keyword(s):  
Food Safety ◽  
High Resolution ◽  
Human Health ◽  
Single Spore ◽  
Wide Range ◽  
Fundamental Challenge ◽  
Microbial System

AbstractMapping where an object has been is a fundamental challenge for human health, commerce, and food safety. Location-specific microbes offers the potential to cheaply and sensitively determine object provenance. We created a synthetic, scalable microbial spore system that identifies object provenance in under one hour at meter-scale resolution and near single spore sensitivity, and that can be safely introduced into and recovered from the environment. This system solves the key challenges in object provenance: persistence in the environment, scalability, rapid and facile decoding, and biocontainment. Our system is compatible with SHERLOCK, facilitating its implementation in a wide range of applications.

Histochemical aspects of nucleic acid detection

1995 ◽  
Vol 53 ◽  
pp. 746-747
Author(s):  
B. A. Hamkalo ◽  
Elizabeth R. Unger
Keyword(s):  
In Situ Hybridization ◽  
Nucleic Acid ◽  
High Resolution ◽  
Dna Sequences ◽  
Single Copy ◽  
Nucleic Acid Detection ◽  
Metaphase Chromosomes ◽  
Potential Applications ◽  
Nucleic Acid Sequences

This symposium brings together several approaches for the detection of specific nucleic acid sequences that have potential applications at the histochemical level.Trask et al. report on the use of fluorescence in situ hybridization (FISH) techniques to study the arrangement of DNA sequences in normal and diseaserelated chromosomes. The sites of specific DNA sequences can be fluorescently tagged. Different sequences can be labeled with different fluorochromes so that their arrangement can be studied using fluorescence microscopy. The distances between points on the same or different chromosomes can be determined in a large number of interphase nuclei or metaphase chromosomes. A variety of probe types, ranging from single-copy sequences to highly repeated sequences can be employed.Hamkalo and co-workers have used non-radioactive methods at the EM level for the detection of nucleic acid sequences by in situ hybridization. Analysis of metaphase chromosomes by electron microscopy allows for high resolution mapping of chromosomes. A variety of labelling procedures have been employed to illustrate the utility of high resolution nucleic acid sequence mapping in these preparations.

scholarly journals A low-cost smart system for electrophoresis-based nucleic acids detection at the visible spectrum

2020 ◽  
Author(s):  
Eduardo Nogueira Cunha ◽  
Maria Fernanda Bezerra de Souza ◽  
Daniel Carlos Ferreira Lanza ◽  
João Paulo Matos Santos Lima
Keyword(s):  
Nucleic Acid ◽  
Point Of Care ◽  
Low Cost ◽  
Visible Spectrum ◽  
Nucleic Acid Detection ◽  
Additional Risk Factor ◽  
Documentation System ◽  
Smart System ◽  
Wide Range ◽  
Image Capturing

ABSTRACTNucleic acid detection by electrophoresis is still a quick and accessible technique for many diagnosis methods, primarily at research laboratories or at the point of care units. Standard protocols detect DNA/RNA molecules through specific bound chemical dyes using a UV-transilluminator or UV-photo documentation system. However, the acquisition costs and availability of these devices, mainly the ones with photography and internet connection capabilities, can be prohibitive, especially in developing countries public health units. Also, ultraviolet radiation is a common additional risk factor to professionals that use electrophoresis-based nucleic acid detection. With that in mind, this work describes the development of a low-cost DNA/RNA detection smart system capable of obtaining qualitative and semi-quantitative data from gel analysis. The proposed device explores the visible light absorption range of commonly used DNA/RNA dyes using readily available parts, and simple manufacturing processes, such as light-emitting diodes (LEDs) and 3D impression. By applying IoT techniques, our system covers a wide range of color spectrum in order to detect bands from various commercially used dyes, using Bluetooth communication and a smartphone for hardware control, image capturing, and sharing. The project also enables process scalability and has low manufacturing and maintenance costs. The use of LEDs at the visible spectrum can achieve very reproducible images, providing a high potential for rapid and point-of-care diagnostics as well as applications in several fields such as healthcare, agriculture, and aquaculture.

scholarly journals SARS-CoV-2 detection with CRISPR diagnostics

2020 ◽  
Author(s):  
Lu Guo ◽  
Xuehan Sun ◽  
Xinge Wang ◽  
Chen Liang ◽  
Haiping Jiang ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Cross Reactivity ◽  
Nucleic Acid Amplification ◽  
Nucleic Acid Detection ◽  
Sample Treatment ◽  
The Novel ◽  
Treatment Protocols ◽  
Design And Optimization ◽  
Detection Assay ◽  
Novel Coronavirus

AbstractThe novel coronavirus (CoV) disease termed COVID-19 (Coronavirus Disease-19) caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) is causing a massive pandemic worldwide, threatening public health systems across the globe. During this ongoing COVID-19 outbreak, nucleic acid detection has played an important role in early diagnosis. Here we report a SARS-CoV-2 detection protocol using a CRISPR-based CRISPR diagnostic platform - CDetection (Cas12b-mediated DNA detection). By combining sample treatment protocols and nucleic acid amplification methods with CDetection, we have established an integrated viral nucleic acid detection platform - CASdetec (CRISPR-assisted detection). The detection limit of CASdetec for SARS-CoV-2 pseudovirus is 1 × 104 copies/mL, with no cross reactivity observed. Our assay design and optimization process can provide guidance for future CRISPR-based nucleic acid detection assay development and optimization.

scholarly journals A programmable pAgo nuclease with universal guide and target specificity from the mesophilic bacterium Kurthia massiliensis

2021 ◽  
Author(s):  
Ekaterina Kropocheva ◽  
Anton Kuzmenko ◽  
Alexei A. Aravin ◽  
Daria Esyunina ◽  
Andrey Kulbachinskiy
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acid Detection ◽  
Bacterial Cells ◽  
Dna And Rna ◽  
Rna Targets ◽  
Wide Range ◽  
Mesophilic Bacterium ◽  
Strict Specificity ◽  
Programmable Nucleases

ABSTRACTArgonaute proteins are programmable nucleases that are found in both eukaryotes and prokaryotes and provide defense against invading genetic elements. Although some prokaryotic Argonautes (pAgos) were shown to recognize RNA targets in vitro, the majority of studied pAgos have strict specificity toward DNA, which limits their practical use in RNA-centric applications. Here, we describe a unique KmAgo nuclease from the mesophilic bacterium Kurthia massiliensis that can be programmed with either DNA or RNA guides and can precisely cleave both DNA and RNA targets. KmAgo preferentially binds 16-20 nt long 5′-phosphorylated guide molecules with no strict specificity for their sequence and is active in a wide range of temperatures. In bacterial cells, KmAgo is loaded with small DNAs with no obvious sequence preferences suggesting that it can uniformly target genomic sequences. Target cleavage by KmAgo depends on the formation of secondary structure indicating that KmAgo can be used for structural probing of RNA targets. Mismatches between the guide and target sequences greatly affect the efficiency and precision of target cleavage, depending on the mismatch position and the nature of the reacting nucleic acid. These properties of KmAgo open the way for its use for highly specific nucleic acid detection and cleavage.

Padlock Probe-based Rolling Circle Amplification Lateral Flow Assay for Point-of-Need Nucleic Acid Detection

The Analyst ◽  
2021 ◽  
Author(s):  
Sidhartha Jain ◽  
David S. Dandy ◽  
Brian Geiss ◽  
Charles Henry
Keyword(s):  
Food Safety ◽  
Nucleic Acid ◽  
Environmental Monitoring ◽  
Rolling Circle Amplification ◽  
Cost Effective ◽  
Clinical Diagnostics ◽  
Nucleic Acid Amplification ◽  
Nucleic Acid Detection ◽  
Padlock Probe ◽  
Rolling Circle

Sensitive, reliable and cost-effective detection of pathogens has wide ranging applications in clinical diagnostics and therapeutics, water and food safety, environmental monitoring, biosafety and epidemiology. Nucleic acid amplification tests (NAATs)...

scholarly journals Molecular Methods in Food Safety Microbiology: Interpretation and Implications of Nucleic Acid Detection

2014 ◽  
Vol 13 (4) ◽  
pp. 551-577 ◽  
Author(s):  
Siele Ceuppens ◽  
Dan Li ◽  
Mieke Uyttendaele ◽  
Pierre Renault ◽  
Paul Ross ◽  
...  
Keyword(s):  
Food Safety ◽  
Nucleic Acid ◽  
Molecular Methods ◽  
Nucleic Acid Detection

scholarly journals An Integrated Rapid Nucleic Acid Detection Assay Based on Recombinant Polymerase Amplification for SARS-CoV-2

2022 ◽  
Author(s):  
Ying Tang ◽  
Yiqin Wang ◽  
Yuchang Li ◽  
Huai Zhao ◽  
Sen Zhang ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acid Detection ◽  
Detection Assay

Development of a conical anode Fe-gun for low voltage SEM

1988 ◽  
Vol 46 ◽  
pp. 978-979
Author(s):  
T. Miyokawa ◽  
S. Norioka ◽  
S. Goto
Keyword(s):  
High Resolution ◽  
Field Emission ◽  
Low Voltage ◽  
Irradiation Damage ◽  
Cold Cathode ◽  
Virtual Source ◽  
Source Position ◽  
Electrostatic Lens ◽  
Electrostatic Lenses ◽  
Wide Range

Field emission SEMs (FE-SEMs) are becoming popular due to their high resolution needs. In the field of semiconductor product, it is demanded to use the low accelerating voltage FE-SEM to avoid the electron irradiation damage and the electron charging up on samples. However the accelerating voltage of usual SEM with FE-gun is limited until 1 kV, which is not enough small for the present demands, because the virtual source goes far from the tip in lower accelerating voltages. This virtual source position depends on the shape of the electrostatic lens. So, we investigated several types of electrostatic lenses to be applicable to the lower accelerating voltage. In the result, it is found a field emission gun with a conical anode is effectively applied for a wide range of low accelerating voltages.A field emission gun usually consists of a field emission tip (cold cathode) and the Butler type electrostatic lens.

Three-fold astigmatism: An important TEM aberration

1993 ◽  
Vol 51 ◽  
pp. 972-973 ◽  
Author(s):  
O.L. Krivanek ◽  
M.L. Leber
Keyword(s):  
High Resolution ◽  
Spatial Frequency ◽  
Field Emission ◽  
Azimuthal Angle ◽  
Hollow Cone ◽  
Small Probe ◽  
Wide Range ◽  
High Resolution Images ◽  
Image Position

Three-fold astigmatism resembles regular astigmatism, but it has 3-fold rather than 2-fold symmetry. Its contribution to the aberration function χ(q) can be written as:where A3 is the coefficient of 3-fold astigmatism, λ is the electron wavelength, q is the spatial frequency, ϕ the azimuthal angle (ϕ = tan-1 (qy/qx)), and ϕ3 the direction of the astigmatism.Three-fold astigmatism is responsible for the “star of Mercedes” aberration figure that one obtains from intermediate lenses once their two-fold astigmatism has been corrected. Its effects have been observed when the beam is tilted in a hollow cone over a wide range of angles, and there is evidence for it in high resolution images of a small probe obtained in a field emission gun TEM/STEM instrument. It was also expected to be a major aberration in sextupole-based Cs correctors, and ways were being developed for dealing with it on Cs-corrected STEMs.

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