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Marine Algal Secondary Metabolites Are a Potential Pharmaceutical Resource for Human Society Developments
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Somasundaram Ambiga, Raja Suja Pandian, Lazarus Vijune Lawrence, Arjun Pandian, Ramu Arun Kumar, Bakrudeen Ali Ahmed Abdul
Marine fungus like Caldariomyces fumago synthesizes chloroperoxidase is distinctive among peroxidases in that it has a cysteinic thiolate as a fifth axial ligand of the heme rather than an imidazole ligand. This enzyme is extremely versatile: it catalyzes not only peroxidase reactions, but also catalase and monooxygenase reactions, and it’s almost unusual, in that in the presence of H2O2 and halide ions, it can catalyze halogenation reactions. A few oxidoreductases are now available for use in the textile, food, and other fields, and many are being actively developed for future commercialization. Industrial-technical, specialty chemical synthesis, environmental, food, pharmaceutical, and personal healthcare are some of the industries where oxidoreductase is used. Oxidoreductase-based biocatalysts fit well with the creation of highly effective, economic, and ecologically friendly industries because they are specialized, energy-saving, and biodegradable.
Macronutrients
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
The name of an enzyme has two parts. The first part is the name of the substrate, and the second part is terminated with a suffix -ase (54). For example, protease is an enzyme of the substrate protein. For the international nomenclature, the name of an enzyme is preceded by the two letters EC (Enzyme Commission) followed by four numbers. For example, E.C.2.7.1.1. The first number denotes one of the six main classes: oxidoreductases, transferases, hydrolases, lyases, isomerases, and ligases. The second number denotes the subclass and the third number denotes the sub-subclass. The last number denotes the serial number of the enzyme in its sub-subclass (53–54). Enzymes are classified based on the reactions they catalyze into six classes cited above. Oxidoreductases such as glutathione reductase, lactate dehydrogenase, and glucose-6-phosphate dehydrogenase are the enzymes that catalyze oxidation-reduction reactions of their substrates. Transferases transfer a functional group between two substrates such as a methyl or phosphate group. Hydrolases catalyze the hydrolysis reactions of carbohydrates, proteins, and esters. Lyases cleave various chemical bonds by other means than hydrolysis and oxidation for the formation of double bonds. Isomerases are involved in isomerization of substrate where interconversion of cis-trans isomers is implicated. Ligases such as alanyl-t-RNA synthetase, glutamine synthetase, and DNA ligases join together two substrates with associated hydrolysis of a nucleoside triphosphate (53–54).
Biocatalysts: The Different Classes and Applications for Synthesis of APIs
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
The enzyme classification adopted by the Enzyme Commission of the IUB is based on a hierarchically ordered sequence of numbers EC w.x.y.z: The first number denotes the general class (e.g., transferase, “2”). The second and the third number refer to the mechanism of the catalyzed reaction but allow to distinguish between different activities (e.g., transferring C1-groups, “2.1” together with methyltransferase, “2.1.1”). The forth number is a serial one within the sub-subclass. It is in the nature of such classification that it makes no distinction between enzymes catalyzing the same type of reaction but being of different sources, so that they may differ from each other with respect to chemical or physical properties due to which they can be separated from each other by physical methods. A similar situation exists in case of isoforms of enzymes that underwent different post-translational modifications. Enzymes belonging to the first enzyme class are oxidoreductases (EC 1.-.-.-) catalyzing oxidation-reduction reactions. If the catalyzed reaction is the oxidation of an alcohol (EC 1.1.-.-), the enzyme acts on the −CHR-OH group of the donor, being oxidized by donating hydrogen or an electron to the acceptor, e.g., NAD+ (EC 1.1.1.-). The fourth digit is a running number; the resulting systematic name is alcohol: NAD oxidoreductase with the EC classification 1.1.1.1 and the common name alcohol dehydrogenase. All enzymes have a systematic and a common name and are subdivided into six general classes as compiled in Table 7.1.
Cytotoxicities and wound healing effects of contact lens multipurpose solution on human corneal epithelial cell
Published in Clinical and Experimental Optometry, 2022
Su Hwan Park, Sung Hee Park, Hak Sun Yu, Jonghoon Shin, Su Jin Kim, Ji Eun Lee
Exploring the cytotoxic effects of the components present in MPS on the cornea is warranted. In the present study, the cytotoxicity and wound healing effects of five commercially available MPSs were analysed according to their composition and concentration. The MTT assay was used to measure the enzymatic activity of NADPH-dependent cellular oxidoreductase, as it reflects mitochondrial activity and cell viability. The presence of LDH, a cytosolic enzyme, was used as an indicator of cell membrane damage that reflects cytotoxicity. The present results indicate significantly reduced cell survival and increased cell lysis in all MPS-treated cells at 6 h and 24h after exposure. All the tested MPSs proved toxic to HCECs, which is consistent with the findings of previous studies.11,27–29 However, the extent of cytotoxicity differed depending on the type of the MPS; higher toxicity was associated with Boston, DL, and NY.
Effects of chronic exposure to low levels of IR on Medaka (Oryzias latipes): a proteomic and bioinformatic approach
Published in International Journal of Radiation Biology, 2021
Yeni Natalia C. Perez-Gelvez, Alvin C. Camus, Robert Bridger, Lance Wells, Olin E. Rhodes, Carl W. Bergmann
Annotation and enrichment analysis via the Blast2GO software was used to further investigate biological processes (BP), molecular functions (MF), and cellular components (CC) that were impacted as a result of chronic exposure to different levels of IR. The two tissue groups (Carcasses and Organs) were analyzed separately. Tables S4 and S5 in Supplementary File 1 present the list of the enrichment GO terms. Figures 5–7 summarize the CirGO information by molecular function (MF), biological process (BP), and cellular components (CC) respectively. The percentages presented in Figures 5–7 refer to the percent of the aggregate of the representations of each one of the enrichment terms after a specific dose of IR. In carcasses, most of the MF of DAPs in carcasses correspond to binding functions (especially at medium and high doses), or ion channel activity (as much as 65.4% at high doses among the overexpressed proteins). After exposure to low levels of IR, the highest percentages of MF terms correspond to exopeptidase activity (35.4%, in the overexpressed proteins) and phosphotransferase activity (50%, among the underexpressed proteins). In organs, when sorting by molecular function, binding related terms after exposure to either low or medium doses were most prevalent among overexpressed proteins. The highest represented percentage of the molecular function of the underexpressed proteins is related to oxidoreductase activity, especially at medium and high doses.
A metabolic pathway for the prodrug nabumetone to the pharmacologically active metabolite, 6-methoxy-2-naphthylacetic acid (6-MNA) by non-cytochrome P450 enzymes
Published in Xenobiotica, 2020
Kaori Matsumoto, Tetsuya Hasegawa, Kosuke Ohara, Chihiro Takei, Tomoyo Kamei, Junichi Koyanagi, Tamiko Takahashi, Masayuki Akimoto
Several drugs containing alkyl side chains are metabolized to the corresponding ω-carboxylic acids by ADH and ALDH following initial ω-hydroxylation by CYP enzymes or others. Incubations with S9 fractions inferred that 6-MNE-ol was a substrate for NAD+-dependent enzymes. Many cytosolic oxidoreductases are capable of oxidizing the primary alcohol to the corresponding aldehyde using NAD+ as a cofactor, which is then converted to its reduced form, NADH. The present results indicated that the oxidized form of the cofactor NAD+ was required for the metabolism of nabumetone to 6-MNA in this process (Figure 6). As a general inhibitor of alcohol dehydrogenases, 4-MP, which is a NAD+-requiring enzyme, markedly inhibited the formation of 6-MNA (Figure 7). These results were consistent with the cofactor-dependent formation of 6-MNA. The sole end-product, 6-MNA, was definitely formed from 6-MNA-ol.