Biomaterial Database

Steviol glycoside biosynthesis. 2007

J E Brandle, and P G Telmer

Southern Crop Protection and Food Research Center, 1391 Sandford Street, London, Ont., Canada N5V 4T3. brandleje@agr.gc.ca

Steviol glycosides are found in high concentrations in the leaves of the Paraguayan perennial herb Stevia rebaudiana and their intense sweetness, as well as high concentration in Stevia leaf tissue, has made them the subject of research interest for over 100 years. Steviol glycosides are diterpenoids whose biosynthetic pathways share four steps in common with gibberellic acid formation. The convergence of genomics and plant biochemistry has led to the rapid elucidation of the genes coding for the various enzymes in the biosynthetic pathway. Functional characterization of the enzymes coded for by those genes is on-going. The first committed step in the pathway is the synthesis of the aglycone steviol and the various glycosides found in the leaf tissue result from the elaboration of steviol by a number of glucosyltransferases.

UI	MeSH Term	Description	Entries
D009097	Multienzyme Complexes	Systems of enzymes which function sequentially by catalyzing consecutive reactions linked by common metabolic intermediates. They may involve simply a transfer of water molecules or hydrogen atoms and may be associated with large supramolecular structures such as MITOCHONDRIA or RIBOSOMES.	Complexes, Multienzyme
D006027	Glycosides	Any compound that contains a constituent sugar, in which the hydroxyl group attached to the first carbon is substituted by an alcoholic, phenolic, or other group. They are named specifically for the sugar contained, such as glucoside (glucose), pentoside (pentose), fructoside (fructose), etc. Upon hydrolysis, a sugar and nonsugar component (aglycone) are formed. (From Dorland, 28th ed; From Miall's Dictionary of Chemistry, 5th ed)	Glycoside
D001692	Biological Transport	The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.	Transport, Biological,Biologic Transport,Transport, Biologic
D013729	Terpenes	A class of compounds composed of repeating 5-carbon units of HEMITERPENES.	Isoprenoid,Terpene,Terpenoid,Isoprenoids,Terpenoids
D014617	Vacuoles	Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.	Vacuole
D015394	Molecular Structure	The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.	Structure, Molecular,Molecular Structures,Structures, Molecular
D016695	Glycosyltransferases	Enzymes that catalyze the transfer of glycosyl groups to an acceptor. Most often another carbohydrate molecule acts as an acceptor, but inorganic phosphate can also act as an acceptor, such as in the case of PHOSPHORYLASES. Some of the enzymes in this group also catalyze hydrolysis, which can be regarded as transfer of a glycosyl group from the donor to water. Subclasses include the HEXOSYLTRANSFERASES; PENTOSYLTRANSFERASES; SIALYLTRANSFERASES; and those transferring other glycosyl groups. EC 2.4.	Glycosyltransferase,Glycoside Transferases,Transferases, Glycoside
D045786	Diterpenes, Kaurane	A group of DITERPENES cyclized into four rings.	Ent-Kaurane,Ent-Kaurene,Kaurane,Kaurane Diterpenoid,Kaurane Diterpenoids,Ent-Kauranes,Ent-Kaurenes,Kauranes,Diterpenoid, Kaurane,Diterpenoids, Kaurane,Ent Kaurane,Ent Kaurene,Kaurane Diterpenes