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Arsenals of Pharmacotherapeutically Active Proteins and Peptides: Old Wine in a New Bottle
Published in Debarshi Kar Mahapatra, Swati Gokul Talele, Tatiana G. Volova, A. K. Haghi, Biologically Active Natural Products, 2020
On the basis of number of amino acids present, peptides can be classified as: Dipeptide which contains two amino acid residues.Tripeptide which contains three amino acid residues.Tetrapeptide which contains four amino acid residues.Oligopeptides which contain less than 10 amino acid residues.Polypeptides which contain 50 or less than 50 amino acid residues.
Synthesis of Bioactive Peptides for Pharmaceutical Applications
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Jaison Jeevanandam, Ashish Kumar Solanki, Shailza Sharma, Prabir Kumar Kulabhusan, Sapna Pahil, Michael K. Danquah
The short chains of amino acid monomers are grouped together with peptide bond linkages to form a beneficial biological entity called peptide. These peptides are classified into dipeptide, which is the shortest peptide, tripeptide, and polypeptide based on the number of amino acids required for peptide formation. Peptides contain less than 50 amino acids and are different from proteins which contain functional polypeptides bound with ligands or genetic material. Also, peptides are highly beneficial in molecular biology as they allow the formation of antibiotic peptides without the requirement of purified protein (Muheem et al., 2016). Recently, peptides are used in mass spectroscopy for the identification of protein structure and function, by analyzing sequences and masses of peptide (Aebersold and Mann, 2016). Moreover, inhibitory peptides are utilized to inhibit the proteins related to diseases and are broadly utilized as a curative agent of deadly diseases (Risitano et al., 2014). The synthesis procedure of peptides determines their properties and thus, they are classified based on the method of synthesis used for peptide formation. Bioactivity is an important property of peptides and thus bioactive peptides are widely used in biomedical pharmaceutical applications. Ribosomal, non-ribosomal, peptones, milk-based and peptide fragments are the sub-classes of bioactive peptides that possess enormous applicational importance (Korhonen et al., 2006).
Nanostructured Cellular Biomolecules and Their Transformation in Context of Bionanotechnology
Published in Anil Kumar Anal, Bionanotechnology, 2018
Amino acids are linked together in a polypeptide chain by peptide bond. The linkage between amino acids occurs through simple condensation reaction between the α-amino groups of one amino acid with α-carboxyl group of another amino acid with the release of a water molecule. Linked amino acids in a polypeptide chain are called amino acid residues. The free amino group and carboxyl group at the opposite ends of peptide chain are called the N-terminal and C-terminal, respectively. During protein synthesis, polypeptide chain formation starts from N-terminal of amino acid (usually methionine) and continues toward the C-terminals by adding one amino acid at a time. Depending on the number of amino acids linked together, they are termed as dipeptide, tripeptide, oligopeptide, and polypeptide. Dipeptide contains two amino acids linked by one peptide bond. Therefore, each peptide chain has one free amino and carboxyl group at opposite ends (Moran et al. 2012).
Environmentally friendly recycling system for epoxy resin with dynamic covalent bonding
Published in Science and Technology of Advanced Materials, 2021
Hsing-Ying Tsai, Takehiro Fujita, Siqian Wang, Masanobu Naito
In this paper, we proposed an environmentally friendly recycling system of ERD that mimics the drug metabolism in living organisms. Herein, we focused on glutathione (γ-glutamyl-cysteinyl-glycine, GSH), cysteine-containing tripeptide as a waterborne thiol-containing reductant. GSH is renowned as a natural antioxidant in organism. GSH has an antioxidant effect by reducing reactive oxygen species and peroxides using its own thiol group, and a detoxification effect by S-S bonding (glutathione conjugation) to the thiol group of cysteine residues of various poisons and drugs, thereby playing a role in protecting against cell injury and death, canceration, and aging [22–25]. Here, we expected that waterborne GSH enables us to mediate cleavages of the disulfide bonding in ERD by thiol-disulfide exchange reaction. Consequently, ERD was disassembled into small oligomers under the mediation of GSH at room temperature in water/organic solvent binary system. The resulting liquid epoxy residue as decomposition was curable upon heating at 180°C for 6 hours by regeneration of disulfide bonding among ERD residues. The obtained solid ERD exhibited 90% of storage modulus compared to the virgin epoxy resin, and the value was almost identical even after several recycling cycles. Finally, CFRP structure was fabricated with ERD (CFRP-ERD). The CFRP-ERD was decomposed using GSH aqueous solution and the carbon fibers were successfully recovered without contamination of ERD. It was further demonstrated that the liquid ERD residue could be cured to form ERD again.
Involvement of glutathione and glutathione metabolizing enzymes in Pistia stratiotes tolerance to arsenite
Published in International Journal of Phytoremediation, 2020
Fernanda Vidal de Campos, Juraci Alves de Oliveira, Adinan Alves da Silva, Cleberson Ribeiro, Sebastián Giraldo Montoya, Fernanda dos Santos Farnese
Our results showed that P. stratiotes is able to accumulate and retain large amount of AsIII in a short time of exposure, presenting high potential for phytoremediation of aquatic environments. In addition, P. stratiotes maintains positive growth rate and minimal cellular damage when exposed to low and moderate AsIII concentrations which is an indication of the ability of the plant to detoxify the metalloid. Glutathione seems to play a central role in AsIII detoxification in Pistia stratiotes, since AsIII uptake was accompanied by increase of both glutathione biosynthesis and the activity of enzymes involved in the metabolism of this tripeptide. This hypothesis is reinforced by the fact that the most marked decrease in growth and the appearance of cellular damage coincided with the impairment of glutathione metabolism. In fact, glutathione synthesis and/or regeneration systems can also be compromised by the toxicity of the pollutant, which would probably result in plant death if the exposure period were longer. Thus, it is possible to conclude that Pistia stratiotes is an interesting plant for programs aimed at the remediation of arsenic-contaminated environments and its ability to detoxify the pollutant correlates with the activity and integration of the enzymes involved in glutathione metabolism.
Investigation of metallothionein level, reduced GSH level, MDA level, and metal content in two different tissues of freshwater mussels from Atatürk Dam Lake coast, Turkey
Published in Chemistry and Ecology, 2019
Organisms in aquatic ecosystems have developed various protective mechanisms against environmental conditions and pollution [17]. Long-term exposure to environmental pollutants may cause a variety of damage to aquatic organisms [18]. The intracellular level of reactive oxygen species (ROS) in aquatic organisms can be increased in the presence of excess metal. To protect against ROS damage, organisms have developed complex antioxidants and detoxifying mechanisms that can inhibit ROS production [15,19,20]. Several biochemical markers are used to evaluate the oxidative stress in mussels that are exposed to metals [21]. Glutathione (GSH) is a tripeptide composed of glutamic acid, cysteine, and glycine amino acids. It is an intracellular antioxidant that plays an important role in xenobiotic damage, cellular defense, detoxification of drugs, and controling the release of ROS [22,23]. Malondialdehyde (MDA) is a product of lipid hydroperoxidation and is considered an important biochemical marker for chemical damage in mussels exposed to aquatic pollutants such as metals [24–26]. Metal-binding proteins such as metallothioneins (MT) are widely used as an important biochemical marker for both oxidative stress and metal toxicity. Because of their high cysteine content, they play an active role in the scavenging of free radicals [21,27]. It is also well known that they have important roles in metal homeostasis and metal detoxification because of their high affinity to metal ions [21].