Adenosine triphosphate (ATP) is an organic compound that provides energy to drive many processes in living cells, such as muscle contraction, nerve impulse propagation, condensate dissolution, and chemical synthesis. Found in all known forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer. When consumed in metabolic processes, it converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. The human body recycles its own body weight equivalent in ATP each day. It is also a precursor to DNA and RNA, and is used as a coenzyme.
In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid H
3PO
4.
The urea cycle (also known as the ornithine cycle) is a cycle of biochemical reactions that produces urea (NH2)2CO from ammonia (NH3). Animals that use this cycle, mainly amphibians and mammals, are called ureotelic.
Adenosine monophosphate (AMP), also known as 5'-adenylic acid, is a nucleotide. AMP consists of a phosphate group, the sugar ribose, and the nucleobase adenine; it is an ester of phosphoric acid and the nucleoside adenosine. As a substituent it takes the form of the prefix adenylyl-.
An anaerobic organism or anaerobe is any organism that does not require molecular oxygen for growth. It may react negatively or even die if free oxygen is present. In contrast, an aerobic organism (aerobe) is an organism that requires an oxygenated environment. Anaerobes may be unicellular or multicellular. Most fungi are obligate aerobes, requiring oxygen to survive. However, some species, such as the Chytridiomycota that reside in the rumen of cattle, are obligate anaerobes; for these species, anaerobic respiration is used because oxygen will disrupt their metabolism or kill them. Deep waters of the ocean are a common anoxic environment.
Thylakoids are membrane-bound compartments inside chloroplasts and cyanobacteria. They are the site of the light-dependent reactions of photosynthesis. Thylakoids consist of a thylakoid membrane surrounding a thylakoid lumen. Chloroplast thylakoids frequently form stacks of disks referred to as grana. Grana are connected by intergranal/stromal thylakoids, which join granum stacks together as a single functional compartment.
Polyphosphates are salts or esters of polymeric oxyanions formed from tetrahedral PO4 (phosphate) structural units linked together by sharing oxygen atoms. Polyphosphates can adopt linear or a cyclic ring structures. In biology, the polyphosphate esters ADP and ATP are involved in energy storage. A variety of polyphosphates find application in mineral sequestration in municipal waters, generally being present at 1 to 5 ppm. GTP, CTP, and UTP are also nucleotides important in the protein synthesis, lipid synthesis, and carbohydrate metabolism, respectively. Polyphosphates are also used as food additives, marked E452.
Carbamoyl phosphate is an anion of biochemical significance. In land-dwelling animals, it is an intermediary metabolite in nitrogen disposal through the urea cycle and the synthesis of pyrimidines. Its enzymatic counterpart, carbamoyl phosphate synthetase I, interacts with a class of molecules called sirtuins, NAD dependent protein deacetylases, and ATP to form carbamoyl phosphate. CP then enters the urea cycle in which it reacts with ornithine to form citrulline.
Glutamate dehydrogenase is an enzyme observed in both prokaryotes and eukaryotic mitochondria. The aforementioned reaction also yields ammonia, which in eukaryotes is canonically processed as a substrate in the urea cycle. Typically, the α-ketoglutarate to glutamate reaction does not occur in mammals, as glutamate dehydrogenase equilibrium favours the production of ammonia and α-ketoglutarate. Glutamate dehydrogenase also has a very low affinity for ammonia, and therefore toxic levels of ammonia would have to be present in the body for the reverse reaction to proceed. However, in brain, the NAD+/NADH ratio in brain mitochondria encourages oxidative deamination. In bacteria, the ammonia is assimilated to amino acids via glutamate and aminotransferases. In plants, the enzyme can work in either direction depending on environment and stress. Transgenic plants expressing microbial GLDHs are improved in tolerance to herbicide, water deficit, and pathogen infections. They are more nutritionally valuable.
Plastoquinone (PQ) is an isoprenoid quinone molecule involved in the electron transport chain in the light-dependent reactions of photosynthesis. The most common form of plastoquinone, known as PQ-A or PQ-9, is a 2,3-dimethyl-1,4-benzoquinone molecule with a side chain of nine isoprenyl units. There are other forms of plastoquinone, such as ones with shorter side chains like PQ-3 as well as analogs such as PQ-B, PQ-C, and PQ-D, which differ in their side chains. The benzoquinone and isoprenyl units are both nonpolar, anchoring the molecule within the inner section of a lipid bilayer, where the hydrophobic tails are usually found.
In the mitochondrion, the matrix is the space within the inner membrane. The word "matrix" stems from the fact that this space is viscous, compared to the relatively aqueous cytoplasm. The mitochondrial matrix contains the mitochondrial DNA, ribosomes, soluble enzymes, small organic molecules, nucleotide cofactors, and inorganic ions.[1] The enzymes in the matrix facilitate reactions responsible for the production of ATP, such as the citric acid cycle, oxidative phosphorylation, oxidation of pyruvate, and the beta oxidation of fatty acids.
Glutamine synthetase (GS) is an enzyme that plays an essential role in the metabolism of nitrogen by catalyzing the condensation of glutamate and ammonia to form glutamine:
Cyanidin is a natural organic compound. It is a particular type of anthocyanidin. It is a pigment found in many red berries including grapes, bilberry, blackberry, blueberry, cherry, chokeberry, cranberry, elderberry, hawthorn, loganberry, açai berry and raspberry. It can also be found in other fruits such as apples and plums, and in red cabbage and red onion. It has a characteristic reddish-purple color, though this can change with pH; solutions of the compound are red at pH < 3, violet at pH 7-8, and blue at pH > 11. In certain fruits, the highest concentrations of cyanidin are found in the seeds and skin. Cyanidin has been found to be a potent sirtuin 6 (SIRT6) activator.
Metabolic wastes or excrements are substances left over from metabolic processes (such as cellular respiration) which cannot be used by the organism (they are surplus or toxic), and must therefore be excreted. This includes nitrogen compounds, water, CO2, phosphates, sulphates, etc. Animals treat these compounds as excretes. Plants have chemical "machinery" which transforms some of them (primarily the nitrogen compounds) into useful substances.
Glutathione synthetase (GSS) is the second enzyme in the glutathione (GSH) biosynthesis pathway. It catalyses the condensation of gamma-glutamylcysteine and glycine, to form glutathione. Glutathione synthetase is also a potent antioxidant. It is found in many species including bacteria, yeast, mammals, and plants.
Mitochondrial carriers are proteins from solute carrier family 25 which transfer molecules across the membranes of the mitochondria. Mitochondrial carriers are also classified in the Transporter Classification Database. The Mitochondrial Carrier (MC) Superfamily has been expanded to include both the original Mitochondrial Carrier (MC) family and the Mitochondrial Inner/Outer Membrane Fusion (MMF) family.
Cobalt chelatase (EC 6.6.1.2) is an enzyme that catalyzes the chemical reaction
Anthocyanins, also called anthocyans, are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical compound that gives flowers a blue color for the first time in his treatise "Die Farben der Blüthen". Food plants rich in anthocyanins include the blueberry, raspberry, black rice, and black soybean, among many others that are red, blue, purple, or black. Some of the colors of autumn leaves are derived from anthocyanins.
The Purine Nucleotide Cycle is a metabolic pathway in protein metabolism requiring the amino acids aspartate and glutamate. The cycle is used to regulate the levels of adenine nucleotides, in which ammonia and fumarate are generated. Adenine converts to AMP, which then coverts into IMP and the byproduct ammonia. IMP converts to S-AMP (adenylosuccinate), which then coverts to AMP and the byproduct fumarate. The fumarate goes on to produce ATP (energy) via oxidative phosphorylation as it enters the Krebs Cycle and then the Electron Transport Chain. Lowenstein first described this pathway and outlined its importance in processes including amino acid catabolism and regulation of flux through glycolysis and the Krebs cycle.
Chlorophyllide a and Chlorophyllide b are the biosynthetic precursors of chlorophyll a and chlorophyll b respectively. Their propionic acid groups are converted to phytyl esters by the enzyme chlorophyll synthase in the final step of the pathway. Thus the main interest in these chemical compounds has been in the study of chlorophyll biosynthesis in plants, algae and cyanobacteria. Chlorophyllide a is also an intermediate in the biosynthesis of bacteriochlorophylls.
