8/13/2019 Metabolic Enzymes
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Metabolic Enzyme Regulation
General Notes
* before regulator means enzyme is phosphorylated by a kinase
(*PKA = Phosphorylated by Protein Kinase A)
* after regulator means enzyme is dephosphorylated
Ca2+ regulates by associating with calmodulin....Ca2+-Calmodulin
complex mediates effects. Assume regulation by PKA is part of the
Glucagon pathway.
ENZYME/PROTEIN ACTIVATION INHIBITION COMMENTS
GLYCOLYSIS
Hexokinase Glucose-6-P
Glucokinase Glucose-6-P Only in Liver
PFK-1 AP
F-!"6-#P
A$P
Ci%ra%eP&P
Lo' (H
Lo' (H - suc) as in
anaero*+ ,lycolysis lac%icaci./
PFK-! AP P&P
Ci%ra%e0PKA
F-6-P --2 F-!"6-#P
3o% a Glycoly%ic&n4y5e+++Provi.es
allos%eric eec%or
Pyruva%e Kinase F-1"6-#P A$P
0PKA
L7H Lac%a%e Cori Cycle liver/
Lac%a%e--2Pyruva%e
P7H Pyruva%e
CoA 8 3A79 8 A7P
Ca!9 8 ,!9
Ace%yl CoA
3A7H
A$P
K3O: &CHA3IS
;e
8/13/2019 Metabolic Enzymes
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ENZYME/PROTEIN ACTIVATION INHIBITION COMMENTS
Fa%%y Acyl CoA
Syn%)e%ase
CP$-I alonyl CoA
Glycerol Kinase
LPL A(oCII ;ecrui%e. %o a(ical surace
o en.o%)elial cells *yInsulin
FA$$Y ACI7 O?I7A$IO3
HSL 0PKA
Fa%%y Acyl CoASyn%)e%ase
FA --2 FAcyl CoAA$P--2AP 9 !Pi/
Loss o $:O )i,)
ener,y ()os()a%es++++
re5e5*er ')en
calcula%in, ener,y yiel./
#-Oxi.a%ion S(iral
&n4y5es
3A7H
FA7!H/
1/ Acyl CoA 7H
!/ &noyl CoA Hy.ra%ase@/ #-Hy.roxy Acyl CoA
7H
/ #-Ke%o $)iolase
K&$O3& #O7Y &$A#OLIS
$)iolase Sequence of Events
Increase. BFA in cy%osol
Balonyl CoA .ecrease.
Increase. i5(or% o FA in%oi%oc)on.ria
Increase. #-Oxi.+
Increase A$P
Increase. 3A7H
#uil. u( o Ace%yl CoA
Ace%yl CoA .iver%e. ro5$CA %o Ke%one #o.ies
Lo'erin, BFA
;eversal o-------Previous
#asically" ke%one *o.ies
are or5e. in %)e
5i%oc)on.rial 5a%rix
')en ace%yl CoA is *ein,(ro.uce. as%er %)an i% can
*e oxi.i4e. in %)e $CA
cycle+
So K#s can *e correla%e.
'i%) )i,) BFA
:i%) res%ora%ion %o nor5al
BFA ++++K# syn%)esis s%o(s*ecause Ace%yl CoA
(reers %o ,o %o $CA
cycle+
HG-CoA Sy%)ase
HG-CoA Lyase
#-Hy.roxy*u%yra%e 7H
Succinyl CoA D AACoA
%ranserase
