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MOF-based Electrochemical Sensors for DNA/RNA/ATP
Published in Ram K. Gupta, Tahir Rasheed, Tuan Anh Nguyen, Muhammad Bilal, Metal-Organic Frameworks-Based Hybrid Materials for Environmental Sensing and Monitoring, 2022
Saadat Majeed, Muhammad Umer Farooq, Sayed Tayyab Raza Naqvi, Batool Fatima, Muhammad Najam-ul-Haq, Sabahat Majeed, Fahad Ali, Naeem Akhtar Khan
DNA is a hereditary material that is helpful for genetic and biological development. It is present in all living organisms, including prokaryotes, eukaryotes, and many viruses. Two spirals are wrapped around each other in a large double-helical-shaped polymer. Each spiral consists of large numbers of monomers known as a nucleotide. Each nucleotide consists of three types of building block: deoxyribose sugar, phosphoric acid, and complementary two base pairs. Base pairs include guanine, cytosine, adenine, and thymine. Nucleotides are covalently attached through the phosphate group of one nucleotide and the sugar of another nucleotide. Two spirals of DNA are connected through hydrogen bonds between nitrogenous bases. There is a specific sequence of bonding of these nitrogenous bases, namely, adenine attaches with thymine through double bonds and guanine with cytosine through triple bonds. High stability in the configuration of DNA molecules is necessary for the replication of new DNA as well as RNA molecules. Each strand of DNA acts as a template for the production of new DNA. DNA is a dense complex of proteins that is present in the nucleus in eukaryotes and cytoplasm in prokaryotes. There is a specific concentration of each base pair in the DNA molecule. Change in concentration of base pairs decreases the immunity that results in many various genetic diseases, tumors, and cancer. Therefore, for clinical purposes detection of DNA is important [8].
Strategies, Design, and Chemistry in Small Interfering RNA Delivery Vehicle Systems for Cancer Therapy
Published in Loutfy H. Madkour, Nanoparticle-Based Drug Delivery in Cancer Treatment, 2022
Chemically modified nucleotides can improve chemical stability and efficacy, increase cell specificity, reduce immunological effects, and decrease off-target effects [174]. siRNA conjugation is one important method to achieve efficacious RNAi both in vitro and in vivo. This section will focus on the chemical modification of nucleotides and synthesis of siRNA.
Methods of Identifying Microbiological Hazards in Indoor Environments
Published in Rafał L. Górny, Microbiological Corrosion of Buildings, 2020
Sequencing is a technique that allows determination of the sequence of nucleotides in the analysed DNA fragment. Its development in the 1970s by Frederick Sanger initiated extensive research aimed at creating genome maps of living organisms. The most famous of the research carried out was completed in 2003: the Human Genome Project. Currently, there is a very extensive, publicly available base that contains genome sequences of almost 260 thousand organism species and various bioinformatics tools for their analysis ‘in silico’. Although in recent years the interest in new sequencing techniques, such as pyrosequencing or next-generation sequencing, is growing, Sanger sequencing is still considered a reference method. It is also still the most commonly used technique to determine nucleotide sequences in the tested fragment of nucleic acid [Benson et al. 2013; Stärk et al. 1998].
A gravity inspired clustering algorithm for gene selection from high-dimensional microarray data
Published in The Imaging Science Journal, 2023
P. Jayashree, V. Brindha, P. Karthik
DNA (Deoxyribonucleic Acid) is a molecule composed of two chains of complex organic molecules called nucleotides. A gene is a sequence of nucleotides within a DNA molecule which stores the content about the synthesis of a ‘gene product’, determining the way a living organism is built and the way it functions. There are four types of nucleotides, by interleaving of which, a DNA strand is formed. These types are designated A (adenine), G (guanine), C (cytosine), and T (thymine). A DNA strand contains chains of nucleotides (called polynucleotide strands) which coil around each other and are bound by hydrogen bonds between complementary nucleotide pairs (called base pairs). The nucleotide types A and T are complementary to each other, with G and C being the other complementary pair. In order for the information present in genes to be expressed, a process called transcription occurs, which converts the encoded information into physical or chemical artefacts in the body of the organism.
An overview of the current progress, challenges, and prospects of human biomonitoring and exposome studies
Published in Journal of Toxicology and Environmental Health, Part B, 2019
Mariana Zuccherato Bocato, João Paulo Bianchi Ximenez, Christian Hoffmann, Fernando Barbosa
Variations in the linear sequence of the genetic code, such as single nucleotide polymorphisms (SNPs), may play a key role in explaining inter-individual differences in structure and function, as well as insight into disease susceptibility and resistance. However, the purpose of our genome is also dependent upon epigenetic mechanisms, which are by definition “beyond the genome,” and include alterations of chromatin structure, involving covalent modification of the central DNA molecule itself, as well as the complex macromolecules that form chromatin. The rapidly evolving field of epigenetics is contributing to our understanding of gene–environment interactions, as epigenetic mechanisms provide additional information on transcriptional control that regulates gene expression (Stricker, Köferle, and Beck 2017).
Comparative proteomic analysis revealed the metabolic mechanism of excessive exopolysaccharide synthesis by Bacillus mucilaginosus under CaCO3 addition
Published in Preparative Biochemistry & Biotechnology, 2019
Hongyu Xu, Zhiwen Zhang, Hui Li, Yujie Yan, Jinsong Shi, Zhenghong Xu
Nucleotides are involved in almost all biochemical processes of the cells; these molecules are precursors of nucleic acid biosynthesis and intermediates of many biosynthesis processes.[34] The three enzymes (polyribonucleotide nucleotidyltransferase, dihydropyrimidinase, and inosine 5′-monophosphate dehydrogenase) were all down-regulated with CaCO3 addition. In the control group, the expression of nucleotide metabolism-related proteins was relatively enhanced and indicates that the substrate used at this time was mainly adopted to maintain the growth of cells themselves. Nucleotide metabolism was inhibited under CaCO3 addition. The utilization of the substrate was high, and additional carbon flux flowed to the direction of polysaccharide synthesis with the growth and reproduction of the substrate.