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Marine algae–degrading enzymes and their applications in marine oligosaccharide preparation
Published in Antonio Trincone, Enzymatic Technologies for Marine Polysaccharides, 2019
Benwei Zhu, Limin Ning, Yun Sun, Zhong Yao
Alginate can be degraded by alginate lyase into unsaturated oligosaccharides with double bonds at the nonreducing end by β-elimination of glycosidic bonds. So far, hundreds of alginate lyases have been identified, purified, and characterized from various sources, and these enzymes have been widely used in the food and pharmaceutical industries (Atala et al. 1994; Fremond et al. 1993; Steinlechnermaran et al. 1996). For instance, they have been used for elucidation of the fine structures of alginate (Boyd and Turvey 1978; Aarstad et al. 2012; Østgaard 1993) and the preparation of protoplast of brown au et algae (Hue et al. 2003; Inoue et al. 2011). Furthermore, alginate lyases also show great potentials in the treatment of cystic fibrosis by degrading the polysaccharide biofilm of bacterium (Hatch and Schiller 1998; Islan et al. 2013, 2014).
Introduction to Sensors
Published in Banshi Dhar Gupta, Anand Mohan Shrivastav, Sruthi Prasood Usha, Optical Sensors for Biomedical Diagnostics and Environmental Monitoring, 2017
Banshi Dhar Gupta, Anand Mohan Shrivastav, Sruthi Prasood Usha
Enzymes are the most common class of bio-recognition elements used in sensing. The first biosensor reported utilized glucose oxidase that was entrapped at a Clark oxygen electrode (Clark and Lyons 1962). The enzymatic reactions are specific, which produce predetermined products where the enzyme acts as a catalyst by deciding the rate of generation of intermediate and by-products. Although the enzymatic reactions are certain to occur, the reaction and its rate are influenced by various factors such as enzyme mounting, stability, pH, temperature, and the environmental conditions in which the sensor is supposed to work. Sometimes, coenzymes are also used to ensure the stability and activity of the enzyme. There are different categories of enzymes according to the reaction catalyzed such as oxidoreductase, transferase, hydrolase, lyase, isomerase, and ligase. The oxidoreductase family of enzymes catalyze the oxidation–reduction reaction, while the transferase catalyzes the transfer of one molecular group to another. The group hydrolases perform the breakage of bonds such as C–O and C–C by hydrolysis reactions. The lyase group of enzymes also perform the breakage of bonds in molecules by using catalytic actions other than hydrolysis and oxidation. Isomerases cause structural changes and molecular rearrangements, while ligases join molecules. The enzymes are immobilized by noncovalent and covalent interactions. Electrostatic adsorption of enzyme has also been reported with good stability. Enzymatic bio-recognition element can be used with optical-, electrochemical-, acoustic-, and calorimetric-type transducers.
Basic Chemical Hazards to Human Health and Safety — I
Published in Jack Daugherty, Assessment of Chemical Exposures, 2020
Transport Enzymes.Transferase enzymes move chemical groups from a substrate molecule such as an acetyl, amino, or methyl group, to a recipient molecule. Gamma Glutamyl Transferase (GGT), for instance, transfers amino acids across cellular membranes. Lyase enzymes remove chemical groups, or segments of molecules, without hydrolysis, and form or split C = C bonds, or add other species to double carbon bonds. Aldolases and carboxylases are typical lyases. Ligase enzymes and the high-energy ATP link other molecules together by forming carbon-to-carbon covalent bonds (C-C) or carbon-sulfur covalent bonds (C-S). Ligases also form C-O-, and C-N bonds.
Understanding the effects of process parameters in the bioscouring of cotton and their interactions on pectate lyase activity by factorial design analysis
Published in The Journal of The Textile Institute, 2025
Bruna Lyra Colombi, Quesli Martins, Cintia Kopsch Imme, Diofer Barboza Da Silva, José Alexandre Borges Valle, Jürgen Andreaus, Manuel José Lis Arias, Rita De Cássia Siqueira Curto Valle
Pectate lyase enzyme is widely employed in bioscouring of natural cellulosic fibers, especially cotton, for the degradation of the pectin layer on the fiber to grant hydrophilicity and allowing subsequent dyeing, printing, and finishing processes (Andreaus et al., 2019; Besegatto et al., 2018). Pectate lyase requires Ca2+ for activity, has an optimum pH for the action in the alkaline region (7.5-10.0), and has an optimum temperature between 40 and 50°C (Uenojo & Pastore, 2007). Bioprep® 3000 L enzyme, specifically, acts efficiently in specific conditions of the pH between 7 and 9 and temperature between 50 and 60°C (Foulk et al., 2008). Along with the enzyme, surfactants are used in many bioscouring formulations. Surfactants act as emulsifiers and detergents for immiscible fatty substances from the fiber surface and make saponification of these hydrophobic impurities (oils and waxes) in the aqueous medium, increasing the wettability of fabrics (Raza et al., 2014). However, if the surfactant interacts with the enzyme, conformational changes may eventually lead to the loss of enzymatic activity (Holmberg, 2018).
Transesterification of vegetable oils into biodiesel by an immobilized lipase: a review
Published in Biofuels, 2023
Akossi Moya Joëlle Carole, Kouassi Konan Edmond, Abolle Abollé, Kouassi Esaie Kouadio Appiah, Yao Kouassi Benjamin
Enzymes are thermolabile proteins, biocatalysts in metabolic reactions. They act at low concentration and have a specificity of action. In modern biotechnology, enzymes catalyze reactions of interest to different industries, such as food, energy, medical or chemical industries. They are classified into seven main categories: oxidoreductases, transferases, hydrolases, lyases, isomerases, ligases, and translocases [46–48]: Oxidoreductases catalyze electron and proton transfers from a donor to a receptor.Example: superoxide anion and hydrogen peroxide.Transferases catalyze the transfer of groups.Example: glutathione S-transferases.Hydrolases catalyze the hydrolysis reactions of molecules.Example: lipases, esterases, proteases, amidases.Lyases catalyze decomposition reactions in which a C-C, C-O, C-N or other bond is broken without hydrolysis or oxidation.Example: fructose, bisphosphate, aldolase.Isomerases catalyze the transfer of groups in the same molecule to produce isomeric forms.Example: triose-phosphate isomerase.Ligases catalyze the joining of two molecules by new covalent bonds with concomitant hydrolysis of Adenosine-triphosphate (ATP) or other similar molecules.Example: glutamine synthetase.Translocases catalyze the movement of ions or molecules across cell membranes in general. Example: extern mitochondrial membrane.