lec 15: amino acid catabolism
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Lec 15: AMINO ACID CATABOLISM. fate of amino nitrogen in mammals. fig 18-1. metabolism of amino nitrogen in liver. fig 18-2. nitrogen removal molecules…. fig 18-2. metabolism of amino nitrogen in liver. fig 18-2. transamination reaction. pg 677. fig 18-5. chemistry of the PLP - PowerPoint PPT PresentationTRANSCRIPT
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Lecture 14 Slides
Glycogen: the glucose buffer…
Glycogen granules
~ 1600 glucose monomers per granule
fig 7-14
Glycogen in real life…
How is glycogen synthesized?
-sequential addition of glucose to a growing a1-4 linked linear polymer
-creation of branches composed of a1-6 linkages
glycogenin, then glycogen synthase
branching enzyme
O1
234
5
6
reducingend
non-reducing
end
Glucose ends…
polymer ends…
fig 7-14
pg 597
fig 15-29
addition of UDP carrier to glucose-1-P
fig 15-30
addition of glucose monomersto the growing glycogen chain
fig 15-31
Glycogen branching enzyme creates branches
fig 15-9
Glycogen branching enzyme creates branches
10a1 4 3
7 a1 6
a1 4
How is glycogen broken down?
-sequential removal of glucose-1P from the non-reducing end
-dismantling of those pesky branches
glycogen phosphorylase
debranching enzyme
fig 14-11
fig 15-26
debranching enzyme removes branches
4
4 a1 6
a1 47a1 4
1 a1 67a1 4
freeglucose
Debranching enzyme removes branches
transferaseactivity
a1-6glucosidase
Ask… ortxt: 858-333-6376
fig 15-36
Allosteric control of glycogen phosphorylase
Hormonal control of glycogen phosphorylase
fig 15-34
fig 15-37
regulation ofglycogen synthaseby phos-phorylationas well…
fig 23-13
Liver glucosemetabolism
Blood glucoselevel is criticaland stringentlyregulated
fig 23-23
fig 23-20
The Coricycle
Liver as a "glucostat"
high blood glucose
low blood glucose
Glucagon: the hormone of starvation
phosphorylation of enzymes
alteration of fructose 2,6 bis P
Insulin: the hormone of plenty
fig 23-24
b cell glucose sensing: an ATP gated channel