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Multiphoton imaging of the retina
Published in Pablo Artal, Handbook of Visual Optics, 2017
Robin Sharma, Jennifer J. Hunter
Coenzymes such as NAD(P)H and flavoproteins like FAD are crucial for mitochondria-based cellular respiration pathways such as oxidative phosphorylation. Many retinal layers are densely packed with mitochondria because the retina is more metabolically active than the brain per unit weight (Wong-Riley, 2010). These molecules are of critical importance for cell survival and play the following roles during cellular respiration: NADH and NADPH are the reduced forms of the coenzymes nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+), respectively, and serve as reducing agents. NADH, a key component of cellular respiration, is generated in the cytoplasm during glycolysis. It is also produced in the mitochondria by the Krebs cycle (also known as the citric acid cycle) during aerobic respiration. NADH donates electrons in complex I, the first stage of the electron transport chain (oxidative phosphorylation), which generates adenosine triphosphate (ATP), a unit of intracellular energy. Thus, glycolysis and the Krebs cycle produce NADH, while the electron transport chain consumes NADH.Flavin adenine dinucleotide (FAD) is also strongly fluorescent. FAD moves electrons between the Krebs cycle and complex II, the second stage of the electron transport chain. FAD is used during the Krebs cycle and produced during the electron transport chain.
Optical Nanosensors
Published in Vinod Kumar Khanna, Nanosensors, 2021
The microdevice was applied to the ECL detection of NADH. “NADH” is an abbreviation for the reduced form of NAD (nicotinamide adenine dinucleotide), a coenzyme found in all living cells, which is converted from its reduced form (NADH) to its oxidized form (NAD+) by dehydrogenase enzymes. Direct imaging of NADH was performed through the NS microarray itself. The ECL microarray showed good temporal stability and reproducibility. The substrate concentration was monitored and imaged by measuring NADH ECL intensity. Therefore, many clinically important analytes are detectable by changing the nature of the dehydrogenase enzyme.
Microbial Metabolism
Published in Maria Csuros, Csaba Csuros, Klara Ver, Microbiological Examination of Water and Wastewater, 2018
Maria Csuros, Csaba Csuros, Klara Ver
NAD is a co-enzyme, derived from the B vitamin nicotinic acid that participates in many biological dehydrogenation reactions. It normally carries a positive charge and can accept one hydrogen atom and two electrons to become the reduced form NADH. NADH is generated during the oxidation of food; it then gives up two electrons (and single proton) to the electron transport chain, thereby reverting to NAD⁺ and generating three molecules of ATP per molecule of NADH.
Higher sirt1 is associated with a better body composition in master sprinters and untrained peers
Published in European Journal of Sport Science, 2023
Patrício Lopes de Araújo Leite, Larissa Alves Maciel, Patrick Anderson Santos, Lucas Pinheiro Barbosa, Sara Duarte Gutierrez, Hugo de Luca Corrêa, Lysleine Alves de Deus, Marcia Cristina Araújo, Samuel da Silva Aguiar, Thiago dos Santos Rosa, John E. Lewis, Herbert Gustavo Simões
Sirt1 (i.e. silent information regulator 1) is one of the seven members of the Sirt family (Sirt1–7) of enzymes and is flexibly involved in several anti-aging pathways. Nicotinamide adenine dinucleotide (NAD+), a deacetylation-dependent coenzyme, is involved in the regulation of different immunometabolic pathways that fight diseases associated with aging (Lavu et al., 2008). Among these pathways, Sirt1 plays an important role in liver fat metabolism by acting on subcutaneous adipose tissue and increasing mitochondrial biogenesis and lipolysis. This enzyme also seems to play a causal role in signalling skeletal-muscle hypertrophy (Koltai et al., 2018; Lavu et al., 2008). However, Sirt1 is reduced in obese individuals, which in turn may accelerate the cellular aging process (Mariani et al., 2020; Stefanowicz et al., 2018). Considering Sirt1′s pleiotropic phenotype, the decrease in its expression is associated with the pathophysiology of several age-related diseases (Kratz et al., 2021; Zhao et al., 2020).
Study on the Improvement of Methane Explosion Inhibition Effect by Ultrafine Water Mist Containing Methanotroph-inorganic Salt
Published in Combustion Science and Technology, 2022
Ke Yang, Chunxiao Yue, Zhixiang Xing, Hong Ji, Yongmei Hao, Jie Wu, Juncheng Jiang
MMO is the first and relatively important enzyme in the metabolic process, which is divided into sMMO present in the cytoplasm and pMMO present in the cell membrane. Sometimes two enzymes are expressed at the same time, and sometimes the expression of one enzyme restricts the expression of the other enzyme. Compared with sMMO, the expression of pMMO has a greater impact on the affinity of methanotroph, so the enhancement of pMMO activity can improve the degradation efficiency of methanotroph (Prichanont, Leak, Stuckey 1998; Streger et al. 1999). Two auxiliary enzymes appeared in the degradation process of CH4, namely NADH enzyme and NAD+ enzyme. The former is a reduced coenzyme and the latter is an oxidized coenzyme. The main function is to transfer electrons. O2 cannot directly oxidize NADH. But under the action of dehydrogenase, it can be converted into NAD+ (Gassner and Lippard 1999). In the process of respiration, under the action of dehydrogenase, oxygen can be reduced to water. Aerobic bacteria absorb nutrients mainly in this way. With the joint participation of O2, NADH, and NAD+, the nutrients needed for bacterial cell growth are decomposed and converted into substances that can be absorbed by themselves. The oxidized coenzyme NAD+ is mainly produced through a series of complex reactions with the participation of ATP and glutamine deamination.
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
About 11 KO related with the glycerolipids degradation pathway could be observed in the UASB sludge biomass (Figure 5). The most abundant one was the oxidoreductase K00128 (0.049%), aldehyde dehydrogenase (NAD+). This enzyme has a wide specificity, and can catalyze the reduction of the NAD+ to NADH using an aldehyde and a molecule of H2O, concomitantly generating a carboxylate and H+ in this reaction. In this case, the D-glyceraldehyde is then converted to D-glycerate, in one of the steps of the glycerol degradation before glycolysis. In this way, besides the glycerolipids metabolism, this enzyme is also related to the Glycolysis/Gluconeogenesis, Fatty Acids Degradation, Limonene and pinene degradation and Pyruvate metabolisms, Aminoacids metabolism, among others, which can justify its high proportions in this biomass. In this study, this KO could be mostly related to the bacterial genera Oxobacter (20.4%), Lutibacter (18.4%), Polaribacter (16.3%) and Spirosoma (4.1%).