HydroxysteroidDehydrogenaseApurifiedpowderobtainedfromadaptedcellsofamutantstrain.Activityonandrosteroneonly,noactivityexhibitedontestosterone.Storeat-20°C.REQUIRESSPECIALSHIPPING:ICEPACK≥0.5unitspermgdryweightSource:Pseudomonastestosteroni

I.U.B.:1.1.1.51and1.1.1.50

Hydroxysteroiddehydrogenasescatalyzetheinterconversionofhydroxylandcarboxylgroupsofsteroids.P.testosteroniderivedhydroxysteroiddehydrogenasesareoftwotypes:3-α-hydroxysteroiddehydrogenase(αenzyme)and3-β-hydroxysteroiddehydrogenase(βenzyme).Theαenzymehasamolecularweightof47,000daltons.Theαenzymeoxidizesonly3-α-hydroxysteroidsoftheC19,C21andC24series.Itisinhibitedbyheavymetalsandsulfhydryl-bindingagents.Theβenzymecatalyzestheoxidationof3-β-hydroxysteroidsoftheC19andC21series,17-β-hydroxysteroidsoftheC18,C19andC21series,aswellascertain16-β-hydroxysteroids.Itisinhibitedbyheavymetalsandreducingagents.Theoxidationoftestosteroneisinhibitedby3,17-α-estrADIolandother1,3,5-estradienederivatives.Worthingtonsuppliestwopreparations:onefromtheregularP.testosteroni(ATCC11966)culturewhichproducesboththeαandtheβenzymes,andasecondfromamutantstrainwhichproducesalmostexclusivelytheαenzyme.Byusingboth,theβ-hydroxysteroidcanbedeterminedbydifference.

TechnicalNote:STDHPandSTDHcontainbothαandβactivities.STDHMP,however,containsonlyαactivity.

UnitDefinition:OneUnitreducesonemicromoleofNADperminuteat25°C,pH9.0usingandrosteroneortestosteroneassubstrate.

美国Worthington Biochemical Corporation成立于1947年，位于美国东海岸美丽海滨小城Lakewood, 有超过60年的生产经营历史，是世界上最主要的酶类供应商，是细胞分离酶的专家级公司。同时，也提供DNA/RNA纯化等分子生物学方面的产品。Worthington已经被购买和出售了好几次，并于1987年返回到沃辛顿家族。60年来，Worthington一直保持世界上高纯度酶的主要来源。