Alkaline phosphatase of the developing down feather: Substrates, activators, and inhibitors☆

[摘要] 1.1.Thepatternofactivityofalkalinephosphataseinthedevelopingdownfeatherandthespecificityofthereactionwerestudiedwithrespecttothefollowingsubstrates:sodiumglycerophosphate,disodiump-nitrophenylphosphate,glucose-1-phosphate,glucose-6-phosphate,hexosediphosphate,fructose-6-phosphate,muscleandyeastadenylicacids.2.2.WiththemethodofGomori,thepatternofactivitywasthesame,butofvaryingstrength,withallsubstratesexceptyeastadenylicacid.Mostsubstratesproducedastrongreactioninthemesodermalpulp,withallpartsofthecellsbeingblackenedbyprecipitate;thereactionintheepidermisconsistedofamoderateblackeningofthenucleusandcytoplasmofthecylindercellslyingnexttothepulp,andofthenucleoliinmoreperipheralcells.Withyeastadenylicacidtherewasaprominentreactioninthenucleoliofallcellsandareductionoftheactivityelsewhere.3.3.Withtheazodyemethod,thecytoplasmofthecellsofthemesodermalpulpwashighlyreactive.Aweakerreactionwasfoundintheepidermalcytoplasm.4.4.ThepossibilitythatseveralphosphataseswerecontributingtotheGomorireactionwastestedbyusingMg++,Mn++,Be++,Zn++,Fe+++,HAsO4−−,HAsO3−−,CN−,semicarbazide,iodoacetate,Versene,glycine,alanine,cysteine,histidine,methionine,proline,valine,serine,lysine,andarginineinconjunctionwithseveralofthesubstrates.5.5.Versene,iodoacetate,semicarbazide,Be++,CN−,cysteine,histidine,glycine,alanine,arginine,lysine,andmethionineinhighconcentrationsinhibitedphosphataseactivity.Mn++,Fe+++,andHAsO3−−hadnoapparenteffect.Inlowconcentrations,methionine,proline,andvalinegavesomeindicationofstimulatingactivitywithsodiumglycerophosphate.6.6.Thereactionsoftheadenylicacidsandfructosesugarstotheinhibitorsdifferedfromthoseofothersubstrates.Mg++wasnecessaryforactivitywithmuscleadenylicacid,fructose-6-phosphate,andhexosediphosphate.AthighconcentrationsZn++inhibitedactivitywithallsubstratesexceptfructose-6-phosphate,andinlowconcentrationstimulatedactivitywithyeastadenylicacid.Therewasstrongnucleolaractivitywithyeastadenylicacidinconcentrationsofarsenatewhichinhibitedactivitywithallothersubstrates.Glycinepromotedactivitywithmuscleadenylicacid.Thereactionswithfructosesugarswereblockedbylowerconcentrationsofinhibitorsthanwithsodiumglycerophosphate.7.7.Epidermalphosphatasewasremovedmorereadilybytheinhibitingagentsthanthephosphataseinthepulp.8.8.ThesedatasuggestthatthedevelopingdownfeathercontainsmorethanonephosphatasecapableofutilizingthevarioussubstratesatapHof9.0–9.4.Theyalsosuggestthatthereisatruenucleolarreactionforalkalinephosphatase.

[学科分类] 生物科学（综合）