HMP Flashcards
glucose 6P DH
uses NADP+ and H2O to make NADPH and 6-phosphogluconolactose
inhibited by NADPH
Cell needs NADPH on HMP
@FA syn and detox
oxidative rxns produce NADPH
-nonoxidative rxns convert ribulose 5P to glucose 6P to produce more NADPH
use both pathways
cell needs NADPH and pyruvate on HMP
@RBCs Oxidative and non oxidative rxns used
- oxidative gen NADH ade ribulose 5P
- nonox convert ribulose 5P to fructose 6P and glyceraldehyde 3P which glycolysis converts to pyruvate
use both pathways
Pathways requiring NADPH
Reductive biosyn
cytochrome p450 monooxygenase system
phagocytosis by WBC
Syn of NO
Reduction of H2O2 (ROS)
CYP450 activity
- Add OH group to make toxins/drugs more soluble
- Mitochondrial-biosyn of steroid hormones
- Mitochondrial-Liver-Biosyn of bile and active vit D3
Needs NADPH and Oxygen to function
Glutathione reduction
Glutathione in reduced form=GSH
OHe- to H2O with glutathione
- after reduces to H2O=becomes oxidized and inactive by glutathione reductase
- NADPH re-reduces glutathione using glutathione reductase
Superoxide reaction
Hb-Fe2+O2 to Hb-Fe3+ + O2e-
Spontaneous
Occurs in highly oxidizing environemtnof RBC
Why GSH is important
Glucose 6P DH def what it does and then what occurs (4 things)
won’t make NADPH from glucose 6P (also can’t do HMP pathway)
- ROS accumulate because no GSH re-reduction
- Heinz bodies (precipitation of Hb) are symptomatic
- Worsened by oxidant stress (infections/drugs/fava beans)
- hemolysis by ROS
Favism-Alternate name?
- inheritance
- homo vs hetero?
- why occur?
- Sx
Glucose 6P DH def
-x link recessive
hetero is usually asymptomatic if no oxidant stress
-offers relative resistance to type of malaria
Sx-Heinz bodies, anemia
Malic enzyme
in Malate to pyruvate in lipid synthesizing cells (adipose, mammary gland, liver)
produces 70% total NADPH
Nicotinamide Nucleotide Transhydrogenase
NADH to NADPH (and NAD+ obviously)
Close to glutathione reductase so can product vs ROS coming off ETC from CoQ
