scholarly journals Metrological framework to support accurate, reliable, and reproducible nucleic acid measurements

2021 ◽  
Author(s):  
Mojca Milavec ◽  
Megan H. Cleveland ◽  
Young-Kyung Bae ◽  
Robert I. Wielgosz ◽  
Maxim Vonsky ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Metrology In Chemistry ◽  
Amount Of Substance ◽  
Dna And Rna ◽  
Measurement Results ◽  
Metrological Infrastructure ◽  
Nucleic Acid Analysis ◽  
Primary Focus ◽  
Analysis Working Group ◽  
Measurement Capabilities

Abstract Nucleic acid analysis is used in many areas of life sciences such as medicine, food safety, and environmental monitoring. Accurate, reliable measurements of nucleic acids are crucial for maximum impact, yet users are often unaware of the global metrological infrastructure that exists to support these measurements. In this work, we describe international efforts to improve nucleic acid analysis, with a focus on the Nucleic Acid Analysis Working Group (NAWG) of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM). The NAWG is an international group dedicated to improving the global comparability of nucleic acid measurements; its primary focus is to support the development and maintenance of measurement capabilities and the dissemination of measurement services from its members: the National Metrology Institutes (NMIs) and Designated Institutes (DIs). These NMIs and DIs provide DNA and RNA measurement services developed in response to the needs of their stakeholders. The NAWG members have conducted cutting edge work over the last 20 years, demonstrating the ability to support the reliability, comparability, and traceability of nucleic acid measurement results in a variety of sectors.

High-resolution nucleic acid sequence mapping via in situ hybridization at the Electron Microscope level

1995 ◽  
Vol 53 ◽  
pp. 752-753
Author(s):  
B.A. Hamkalo ◽  
S. Narayanswami ◽  
A.P. Kausch
Keyword(s):  
Nucleic Acid ◽  
Interphase Nucleus ◽  
Genome Mapping ◽  
Precise Location ◽  
Electron Microscope Level ◽  
Rna Sequences ◽  
Fundamental Interest ◽  
Whole Cells ◽  
Dna And Rna

The availability of nonradioactive methods to label nucleic acids an the resultant rapid and greater sensitivity of detection has catapulted the technique of in situ hybridization to become the method of choice to locate of specific DNA and RNA sequences on chromosomes and in whole cells in cytological preparations in many areas of biology. It is being applied to problems of fundamental interest to basic cell and molecular biologists such as the organization of the interphase nucleus in the context of putative functional domains; it is making major contributions to genome mapping efforts; and it is being applied to the analysis of clinical specimens. Although fluorescence detection of nucleic acid hybrids is routinely used, certain questions require greater resolution. For example, very closely linked sequences may not be separable using fluorescence; the precise location of sequences with respect to chromosome structures may be below the resolution of light microscopy(LM); and the relative positions of sequences on very small chromosomes may not be feasible.

scholarly journals Sulfur Modification in Natural RNA and Therapeutic Oligonucleotides

2021 ◽  
Author(s):  
Ya Ying Zheng ◽  
Ying Wu ◽  
Thomas Begley ◽  
Jia Sheng
Keyword(s):  
Nucleic Acid ◽  
Dna And Rna ◽  
Sulfur Modification ◽  
Oxygen Atoms

Sulfur modifications have been discovered on both DNA and RNA. Sulfur substitution of oxygen atoms at nucleobase or backbone locations in the nucleic acid framework led to a wide variety...

scholarly journals Alpha-Helical Fragaceatoxin C Nanopore Engineered for Double-Stranded and Single-Stranded Nucleic Acid Analysis

2016 ◽  
Vol 128 (40) ◽  
pp. 12682-12686 ◽  
Author(s):  
Carsten Wloka ◽  
Natalie Lisa Mutter ◽  
Misha Soskine ◽  
Giovanni Maglia
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acid Analysis

Fully Integrated Lab-on-a-Disc for Nucleic Acid Analysis of Food-Borne Pathogens

2014 ◽  
Vol 86 (8) ◽  
pp. 3841-3848 ◽  
Author(s):  
Tae-Hyeong Kim ◽  
Juhee Park ◽  
Chi-Ju Kim ◽  
Yoon-Kyoung Cho
Keyword(s):  
Nucleic Acid ◽  
Fully Integrated ◽  
Food Borne Pathogens ◽  
Food Borne ◽  
Nucleic Acid Analysis

scholarly journals Recent developments in nucleic acid based techniques for use in rumen manipulation

2009 ◽  
Vol 38 (spe) ◽  
pp. 341-351 ◽  
Author(s):  
Christopher McSweeney ◽  
Seungha Kang ◽  
Emma Gagen ◽  
Carl Davis ◽  
Mark Morrison ◽  
...  
Keyword(s):  
Microbial Community ◽  
Nucleic Acid ◽  
Microbial Communities ◽  
Marker Gene ◽  
Molecular Ecology ◽  
Functional Gene ◽  
Rumen Microorganisms ◽  
Dna And Rna ◽  
Conventional Culture ◽  
Reference Strains

Nucleic acid-based techniques which can be used to characterise complex microbial communities without incubation are now being employed regularly in ruminant nutrition studies. Conventional culture-based methods for enumerating rumen microorganisms (bacteria, archaea, protozoa, and fungi) have been superseded and are now used mainly to obtain pure isolates of novel organisms and reference strains that are required for the development and validation of the nucleic acid approaches. These reference strains are also essential for physiological studies of the lifestyle of the organisms as well as sources of genomic DNA and RNA that can be analysed for functional gene activity. The foundation of the molecular ecology techniques is 16S/18S rDNA sequence analysis which has provided a phylogenetically based classification scheme for enumeration and identification of microbial community members. The use of this marker gene in assays involving the use of single nucleic acid probes or primer sets is rapidly evolving to high throughput approaches such as microarray analysis and new generation sequencing technologies. While these analyses are very informative for determining the composition of the microbial community and monitoring changes in population size, they can only infer function based on these observations. The focus of nucleic acid research is now shifting to the functional analysis of the ecosystem which involves the measurement of functional genes and their expression in the predominant or specific members of the rumen microbial community. Functional gene studies are less developed than 16S rDNA-based analysis of community structure. Also for gene expression studies there are inherent problems involved in extracting high quality RNA from digesta, and priming cDNA synthesis from bacterial mRNA. This paper reviews nucleic acid based molecular methods which have recently been developed for studying the structure and function of rumen microbial communities.

Nucleic acids in prion preparations: unspecific background or essential component?

1994 ◽  
Vol 343 (1306) ◽  
pp. 425-430 ◽  
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Large Scale ◽  
Size Range ◽  
Complete Recovery ◽  
Tissue Homogenate ◽  
Purification Step ◽  
Prolonged Incubation ◽  
Purification Scheme ◽  
Nucleic Acid Analysis

As recently published (Kellings et al. J. gen Vir. 73, 1025-1029 (1992)), the analysis of purified scrapie prions by return refocusing gel electrophoresis revealed remaining nucleic acids in the size range up to 1100 nucleotides. The results defined the possible characteristics of a hypothetical scrapie-specific nucleic acid. If homogeneous in size, such a molecule would be less than 80 nucleotides in length at a particle-toinfectivity ratio (p: i) near unity; if heterogeneous, scrapie-specific nucleic acids would have to include molecules smaller than 240 nucleotides. To decrease the amount of nucleic acids, several modifications of the PrP Sc purification scheme were introduced. Instead of sucrose gradient, ultrafiltration was applied as a purification step and nucleic acids were degraded by BenzonasetM after ultrafiltration, but significant reduction of the p: i ratio could not be achieved. To prevent trapping of nucleic acids in prion rods, nuclease (Benzonase™ ) was added into the tissue homogenate and incubated at 37°C, overnight. The Benzonase treatment revealed no loss of infectivity, but the whole procedure of nucleic acid analysis did not lead to a reduction of the p :i ratio. In another approach the number of nucleic acid degradations steps was reduced to essentially two steps: Zn 2+ hydrolysis and Benzonase digestion. Higher Zn 2+ concentrations and prolonged incubation times resulted in a more efficient nucleic acid degradation. The bioassays yielded complete recovery of infectivity. Large-scale preparations for determining the p: i ratio are still underway

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