Sarsasapogenin 3β-glucosyltransferase

{{Short description|Class of enzymes}}

{{infobox enzyme

| Name = sarsasapogenin 3-β-glucosyltransferase

| EC_number = 2.4.1.193

| CAS_number = 117698-14-3

| GO_code = 0047249

| image =

| width =

| caption =

}}

In enzymology, a sarsasapogenin 3β-glucosyltransferase ({{EC number|2.4.1.193}}) is an enzyme that catalyzes the chemical reaction

:UDP-glucose + sarsasapogenin {{eqm}} UDP + sarsasapogenin 3-O-β-D-glucoside

Thus, the two substrates of this enzyme are UDP-glucose and sarsasapogenin [(3β,5β,25S)-spirostan-3-ol], whereas its two products are UDP and sarsasapogenin 3-O-β-D-glucoside.{{citation | vauthors = Paczkowski C, Wojciechowski ZA | title = The occurrence of UDPG-dependent glucosyltransferase specific for sarsasapogenin in Asparagus officinalis | journal = Phytochemistry | volume = 27 | issue = 9 | year = 1988 | pages = 2743–47 | doi = 10.1016/0031-9422(88)80654-X}}

The enzyme was first isolated from the root of the common asparagus (Asparagus officinalis). It is specific for substrate sterols with the uncommon 5β-configuration (sarsasapogenin and smilagenin), that is with a cis-linkage between the A and B rings of the steroid nucleus.

This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP-glucose:(3β,5β,25S)-spirostan-3-ol 3-O-β-D-glucosyltransferase. This enzyme is also called uridine diphosphoglucose-sarsasapogenin glucosyltransferase.