In molecular biology, biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules. This process often consists of metabolic pathways. Some of these biosynthetic pathways are located within a single cellular organelle, while others involve enzymes that are located within multiple cellular organelles. Examples of these biosynthetic pathways include the production of lipid membrane components and nucleotides. Biosynthesis is usually synonymous with anabolism.
A catalytic triad is a set of three coordinated amino acids that can be found in the active site of some enzymes. Catalytic triads are most commonly found in hydrolase and transferase enzymes. An acid-base-nucleophile triad is a common motif for generating a nucleophilic residue for covalent catalysis. The residues form a charge-relay network to polarise and activate the nucleophile, which attacks the substrate, forming a covalent intermediate which is then hydrolysed to release the product and regenerate free enzyme. The nucleophile is most commonly a serine or cysteine amino acid, but occasionally threonine or even selenocysteine. The 3D structure of the enzyme brings together the triad residues in a precise orientation, even though they may be far apart in the sequence.
Cysteine metabolism refers to the biological pathways that consume or create cysteine. The pathways of different amino acids and other metabolites interweave and overlap to creating complex systems.
In enzymology, a tRNA (guanine-N7-)-methyltransferase (EC 2.1.1.33) is an enzyme that catalyzes the chemical reaction
In enzymology, a tRNA guanosine-2'-O-methyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a 3-mercaptopyruvate sulfurtransferase is an enzyme that catalyzes the chemical reactions of 3-mercaptopyruvate. This enzyme belongs to the family of transferases, specifically the sulfurtransferases. This enzyme participates in cysteine metabolism. It is encoded by the MPST gene.
In enzymology, a cysteine desulfurase is an enzyme that catalyzes the chemical reaction
In enzymology, an arginine—tRNA ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a cysteine—tRNA ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a glutamate—tRNA ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a glutamine—tRNA ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a methionine—tRNA ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a proline—tRNA ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a serine—tRNA ligase is an enzyme that catalyzes the chemical reaction
In enzymology, a threonine-tRNA ligase is an enzyme that catalyzes the chemical reaction
In enzymology, an arginyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a leucyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, an [RNA-polymerase]-subunit kinase is an enzyme that catalyzes the chemical reaction
CCA tRNA nucleotidyltransferase is an enzyme with systematic name CTP,CTP,ATP:tRNA cytidylyl,cytidylyl,adenylyltransferase. This enzyme catalyses the following chemical reaction
Molybdopterin synthase sulfurtransferase is an enzyme with systematic name persulfurated L-cysteine desulfurase:(molybdopterin-synthase sulfur-carrier protein)-Gly-Gly sulfurtransferase. This enzyme catalyses the following chemical reaction
