China
Africa
Explore chapters and articles related to this topic
Cell Physiology
Published in Wei-Shou Hu, Cell Culture Bioprocess Engineering, 2020
The substrate for glycosidic bond formation by glycosyltransferase is a nucleotide sugar. The carbonyl carbon of the sugar is the carbon that will form the glycosidic bond. Before it can react with the glycan substrate, the carbonyl carbon of the sugar substrate (glucose 1-phosphate, galactose 1-phosphate, N-acetyl-glucosamine-phosphate, or mannose 1-phosphate) needs to be “activated” by reacting with a nucleotide (NTPs: UTP, CTP, GTP) to form NDP-sugar or CMP-sialic acid at the expense of an equivalent of 1 ATP. Different sugars are linked to different NDPs. Uracil is used for glucose- and galactose-based sugars (e.g., UDP-glucose and UDP-galactose), guanyl for mannose and fucose, and cytidyl for sialic acid.
Cellulose, the Main Component of Biomass
Published in Jean-Luc Wertz, Magali Deleu, Séverine Coppée, Aurore Richel, Hemicelluloses and Lignin in Biorefineries, 2017
Jean-Luc Wertz, Magali Deleu, Séverine Coppée, Aurore Richel
Cellulose synthases are glycosyltransferases that catalyze the transfer of sugar moieties from activated donor molecules (glycones) to specific acceptor molecules (aglycones), forming glycosidic bonds.22,38,39 These activated molecules are referred to as nucleotide sugars or sugar nucleotides. Nucleotide sugars act as glycosyl donors in glycosylation reactions.
Microbial and functional characterization of granulated sludge from full-scale UASB thermophilic reactor applied to sugarcane vinasse treatment
Published in Environmental Technology, 2022
Franciele Pereira Camargo, Isabel Kimiko Sakamoto, Tiago Palladino Delforno, Cédric Midoux, Iolanda Cristina Silveira Duarte, Edson Luiz Silva, Ariane Bize, Maria Bernadete Amâncio Varesche
Among the main carbohydrate metabolism pathways, the most abundant one, glycolysis and gluconeogenesis (0.50%), citric acid cycle (0.55%), pentose phosphate (0.52%), galactose (0.32%), starch and sucrose (0.42%), amino sugar and nucleotide sugar (0.45%), pyruvate (0.83%), glyoxylate and dicarboxylate (0.70%), butanoate (0.45%), among others (0.91%), stand out. The most abundant genera were Sulfirimonas (11.04%), Defluviitoga (8.02%), Coprothermobacter (6.77%), Fervidobacterium (4.09%), Fluviicola (3.72%), Pseudomonas (2.93%), Marinospirillum (2.67%) and Acetomicrobium (1.99%). Also, Defluviitoga was the most abundant genus in the galactose, starch and sucrose and pentose phosphate pathways.
Metabolomics approach to biomarkers of dry eye disease using 1H-NMR in rats
Published in Journal of Toxicology and Environmental Health, Part A, 2021
Jung Dae Lee, Hyang Yeon Kim, Jin Ju Park, Soo Bean Oh, Hyeyoon Goo, Kyong Jin Cho, Suhkmann Kim, Kyu-Bong Kim
In addition, valine, leucine and isoleucine biosynthesis; glycine, serine and threonine metabolism; phenylalanine metabolism; glyoxylate and dicarboxylate metabolism; pantothenate and CoA biosynthesis; citrate cycle (TCA cycle); pyruvate metabolism; phenylalanine, tyrosine and tryptophan biosynthesis; taurine and hypotaurine metabolism; primary bile acid biosynthesis; histidine metabolism; glycolysis/gluconeogenesis; glutathione metabolism; amino sugar and nucleotide sugar metabolism; and tryptophan metabolism were associated with the pathways of urinary metabolites (Table 2). The expected change of the urinary metabolic pathways in the DED group is illustrated in Figure 10.
Cyanobacteria mediated heavy metal removal: a review on mechanism, biosynthesis, and removal capability
Published in Environmental Technology Reviews, 2021
Abdullah Al-Amin, Fahmida Parvin, Joydeep Chakraborty, Yong-Ick Kim
Wild type cyanobacteria may not be an ideal organism for all types of heavy metal ion removal operations. Every species has some limitations in biosorption [47]. To combat all of these challenges, engineered cyanobacteria may be a good alternative for ideal heavy metal removal operations. Genetic modification enhances anionic moiety in cell surface and alteration of chemical compounds for optimum heavy metal ion adsorption in cell surface [38]. Cyanobacterial EPS is highly complex in nature. Though knowledge in EPS biosynthesis is still insufficient, EPS synthesis pathway engineering may provide insights for optimizing EPS production, which may enhance anionic moiety in the cell surface. The following three approaches can genetically modify the EPS: EPS synthesis is carbon and energy-demanding process. Expressing BicA transporter in Synechocystis sp. strain PCC6803, resulted in enhancing CO2 uptake, faster growth of the cell, and increase of EPS production [67]. Another approach to enhance carbon availability is by reducing carbon sink and other competitive pathways, for example, sucrose, glycosylglycocerol, and glycogen. This approach may shift the carbon sink toward polysaccharide production [58].Sufficient sugar nucleotides can induce high EPS production. Performing metabolism engineering enhances the expression level of enzymes (phosphoglucomutase, UDP-glucose pyrophosphorylase, UDP-glucose dehydrogenase, and UDP-galactose-4-epimerase), responsible for supplying nucleotide sugar precursor might enhance EPS production [68].Assemblance of monosaccharide's repeated unit into polysaccharide may be achieved by overexpressing native glycosyltransferase or recombining heterologous glycosyltransferase genes [69]. And these polysaccharides will be transported outside the cell as EPS.