HintsSheetfor“InhibitionandAllostericRegulationofMonomericPhosphoenolpyruvateCarboxykinaseby3-MercaptopicolinicAcid”MarkD.Balan,MatthewJ.Mcleod,WilliamR.Lotosky,MarkGhaly,andToddHolyoakMetabolicpathwaythatPEPCKisinvolvedin:

PEPCK

O

O

-O

O

O-

oxaloacetate

P

O

O--O O

O

O-

phosphoenolpyruvate

Glycolysisroleinmetabolism:BreakdownglucosetocreateATPandpyruvate.PyruvateisthenusedinthecitricacidcycletoproducemoreATP.Gluconeogenesisroleinmetabolism:Makeglucosefromprecursorsincell,esp.pyruvate.

Hypoglycemicagent=somethingthatleadstolowlevelsofglucose(lowbloodsugar)P-loopmotif=Manyphosphate-bindingproteinshaveaphosphate-bindingloop(P-loop).TheconsensussequenceforthisstructureisGXXXXGKT/S.SkiptheExperimentalsectionunlessyouareinterestedinhowtodocrystallography(wewillnotdiscussitinclass).ReactionmechanismofPEPCK:from:"StructuralInsightsintotheMechanismofPhosphoenolpyruvateCarboxykinaseCatalysis"CarlsonandHolyoak,JBiolChem.2009Oct2;284(40):27037–27041.InthesectionoftheResultsandDiscussionenitledCrystallography,youdon'tneedtopayattentiontothedetailsofthestructuredetermination.Whentheytalkaboutdisorderedloopstheymeanthatsomeloopsintheproteinareflexibleandsoaremissingfromthex-raystructurebecauseitisa"snapshot"oftheproteinstructure.Anythinginmotionisnotclearlyvisible.