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Glossary of scientific and technical terms in bioengineering and biological engineering
Published in Megh R. Goyal, Scientific and Technical Terms in Bioengineering and Biological Engineering, 2018
Z-DNA is a form of DNA, in which the double helix is wound in a left-hand, instead of a right-hand, manner. DNA adopts the Z conformation when purines and pyrimidines alternate on each strand, e.g., 5’CGCGCGCG 3’ or 3’GCGCGCGC5.’ Synonym is zig-zag DNA.
Biosorption of heavy metals from water: mechanism, critical evaluation and translatability of methodology
Published in Environmental Technology Reviews, 2022
Risha Jasmine Nathan, Arvind Kumar Jain, Rhonda J. Rosengren
Nickel: In soils, Ni is found as insoluble sulphides and silicates, as well as soluble compounds [69]. Thus, surface water can be contaminated with Ni by direct leaching from rocks and sediments resulting in human exposure to this toxicant through drinking water. Chronic exposure to Ni leads to accumulation over time and may cause cardiovascular and renal diseases [29,70]. Carcinogenic activity of Ni in humans results due to the fact that the divalent form of this element can initiate carcinogenesis via mutagenesis, chromosome damage, formation of Z-DNA, inhibition of DNA excision-repair or epigenetic mechanisms [71,72]. Sub-chronic exposure to Ni has been reported to cause hyperglycaemia, decrease in serum urea and blood haemoglobin, as well as significantly increase urine urea. The symptoms for sub-chronic toxicity include lethargy, ataxia, hypothermia, salivation, diarrhoea [73].
Water-soluble polycarbodiimides and their cytotoxic and antifungal properties
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Enosha Harshani De Silva, Narges Salamat, Li Zhang, Jie Zheng, Bruce M. Novak
Cytotoxic compounds can be used as cancer therapeutics. DNA-targeted anticancer drugs are the most efficient and novel clinical method [23]. Mustard-gas was the first DNA targeted chemotherapy drug, which was used in World War I and II victims [23]. Chiral compounds [24], oligomers [25], peptides [23], and some metallic supramolecular polymers [20,26] are some examples of DNA interactive anticancer drugs. The previously reported chiral drugs (-)-and (+)-daunorubicin manifest these properties, with the R enantiomer binding B-DNA and the S enantiomer binding Z-DNA [25]. In addition, metal complex helical polymers displayed a high binding affinity towards DNA [27,28]. Also, chiral molecules can be used as DNA templates that could identify DNA [29]. Thus, it was concluded that cytotoxic polymeric materials with chiral and helical structures could display promising anticancer activity. However, significant potential side effects limited their usage as chemotherapeutic agents. Thus, there is a high demand for the continued pursuit of new anticancer agents [30].
Reactivity towards DNA and protein, cellular uptake, cytotoxic activity of a mononuclear copper(II) complex of the thioflavin-T (ThT)-based derivative
Published in Journal of Coordination Chemistry, 2020
Zhanfen Chen, Yixuan Wu, Wangxi Wu, Yumin Zhang
The conformational change of CT-DNA due to the interaction with 1 was measured using circular dichroism (CD). The normal CT-DNA has a right-handed chiral conformation and exists in B-form in solution. The observed CD spectrum of CT-DNA (Figure 5) consists of a positive absorption band at 275 nm due to the base stacking and a negative band at 245 nm due to the right-handed helicity and is characteristic of canonical B-form DNA [32]. Z-form DNA is another major nucleic acid duplex structure, which is a left-handed helix. The structure is generally adopted by oligonucleotides that have sequences of alternating pyrimidines and purines in the presence of high salt concentrations [33]. The CD spectra of Z-DNA are generally characterized by a broad negative band at around 290 nm and a positive band centered at 260–265 nm [34]. Herein, when treated with 1, a visible decrease in the ellipticity and slight red-shift were observed on both the positive and negative bands with an increase in the [1]/[CT-DNA] ratio. Such a changing tendency is an indication of B→Z DNA conformation conversion [34, 35]. However, the conversion remained incomplete and B-DNA still prevailed in solution because the inversion of the CD spectra was not observed in the tested conditions. The results suggest that 1 can indeed alter the tertiary structure of DNA.