In biochemistry, a ligase is an enzyme that can catalyze the joining (ligation) of two molecules by forming a new chemical bond. This is typically via hydrolysis of a small pendant chemical group on one of the molecules, typically resulting in the formation of new C-O, C-S, or C-N bonds. For example, DNA ligase can join two complementary fragments of nucleic acid by forming phosphodiester bonds, and repair single stranded breaks that arise in double stranded DNA during replication.
The glyoxylate cycle, a variation of the tricarboxylic acid cycle, is an anabolic pathway occurring in plants, bacteria, protists, and fungi. The glyoxylate cycle centers on the conversion of acetyl-CoA to succinate for the synthesis of carbohydrates. In microorganisms, the glyoxylate cycle allows cells to use two carbons, such as acetate, to satisfy cellular carbon requirements when simple sugars such as glucose or fructose are not available. The cycle is generally assumed to be absent in animals, with the exception of nematodes at the early stages of embryogenesis. In recent years, however, the detection of malate synthase (MS) and isocitrate lyase (ICL), key enzymes involved in the glyoxylate cycle, in some animal tissue has raised questions regarding the evolutionary relationship of enzymes in bacteria and animals and suggests that animals encode alternative enzymes of the cycle that differ in function from known MS and ICL in non-metazoan species.
Guanosine monophosphate synthetase, also known as GMPS is an enzyme that converts xanthosine monophosphate to guanosine monophosphate.
In enzymology, an L-2-hydroxyglutarate dehydrogenase is an enzyme that catalyzes the chemical reaction
In enzymology, a hydroxyacid-oxoacid transhydrogenase is an enzyme that catalyzes the chemical reaction
The enzyme 4-hydroxy-2-oxoglutarate aldolase catalyzes the chemical reaction
In enzymology, a formate—tetrahydrofolate ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a 2-ethylmalate synthase (EC 2.3.3.6) is an enzyme that catalyzes the chemical reaction
In enzymology, a 2-isopropylmalate synthase (EC 2.3.3.13) is an enzyme that catalyzes the chemical reaction
In enzymology, a 2-methylcitrate synthase (EC 2.3.3.5) is an enzyme that catalyzes the chemical reaction
In enzymology, a 3-ethylmalate synthase (EC 2.3.3.7) is an enzyme that catalyzes the chemical reaction
In enzymology, a 3-propylmalate synthase (EC 2.3.3.12) is an enzyme that catalyzes the chemical reaction
In enzymology, a homocitrate synthase (EC 2.3.3.14) is an enzyme that catalyzes the chemical reaction
In molecular biology, hydroxymethylglutaryl-CoA synthase or HMG-CoA synthase EC 2.3.3.10 is an enzyme which catalyzes the reaction in which acetyl-CoA condenses with acetoacetyl-CoA to form 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA). This reaction comprises the second step in the mevalonate-dependent isoprenoid biosynthesis pathway. HMG-CoA is an intermediate in both cholesterol synthesis and ketogenesis. This reaction is overactivated in patients with diabetes mellitus type 1 if left untreated, due to prolonged insulin deficiency and the exhaustion of substrates for gluconeogenesis and the TCA cycle, notably oxaloacetate. This results in shunting of excess acetyl-CoA into the ketone synthesis pathway via HMG-CoA, leading to the development of diabetic ketoacidosis.
In enzymology, a malate synthase (EC 2.3.3.9) is an enzyme that catalyzes the chemical reaction
In enzymology, a 2-hydroxy-3-oxoadipate synthase (EC 2.2.1.5) is an enzyme that catalyzes the following chemical reaction:
In enzymology, a N-acylneuraminate-9-phosphate synthase (EC 2.5.1.57) is an enzyme that catalyzes the chemical reaction
L-2-hydroxyglutarate dehydrogenase, mitochondrial is an enzyme that in humans is encoded by the L2HGDH gene, also known as C14orf160, on chromosome 14.
3-Deoxy-D-arabinoheptulosonate 7-phosphate (DAHP) synthase is the first enzyme in a series of metabolic reactions known as the shikimate pathway, which is responsible for the biosynthesis of the amino acids phenylalanine, tyrosine, and tryptophan. Since it is the first enzyme in the shikimate pathway, it controls the amount of carbon entering the pathway. Enzyme inhibition is the primary method of regulating the amount of carbon entering the pathway. Forms of this enzyme differ between organisms, but can be considered DAHP synthase based upon the reaction that is catalyzed by this enzyme.
In enzymology, a D-2-hydroxyglutarate dehydrogenase is an enzyme that catalyzes the chemical reaction
