Metabolism High Yield Flashcards
1
Q
Where does beta oxidation occur?
A
mitochondira
2
Q
Where does glycolysis occur?
A
cytoplasm
3
Q
Where does HMP shunt occur?
A
cytoplasm
4
Q
Where does acetyl-CoA production occur?
A
Mitochondria
5
Q
Where does Heme synthesis occur?
A
Both mitochondria and cytoplasm
6
Q
Where does urea cycle occur?
A
mitochondria and cytoplasm
7
Q
Where does TCA cycle occur?
A
Mitcochondria
8
Q
What type of enzyme adds inorganic phosphate onto substrate with NO use of ATP?
A
Phosphorylase
9
Q
What type of enzyme calalyzes oxidation reduction reactions?
A
dehydrogenase
10
Q
What type of enzyme transfers CO2 groups with the help of biotin?
A
Carboxylase
11
Q
What enzyme relocates a functional group within a molecule?
A
Mutase
12
Q
What is the rate determining enzyme of glycolysis?
A
PFK1
13
Q
How does F26BP alter activity of glycolysis?
A
increased activity of PFK1
14
Q
How does citrate alter the activity of glycolysis?
A
increased activity of citrate
15
Q
What is the rate determining enzyme of gluconeogenesis?
A
F16BPase
16
Q
What upregulates F16BPase? What downregulates it?/
A
Upregulate? ATP and acetyl coA
Downregulate- AMP, F26BP
17
Q
What is the rate determining enzyme of TCA cycle?
A
Isocitrate dehydrogenase
18
Q
What inhibits isocitrate dehydrogenase?
A
NADH and ATP
19
Q
What is the rate determining enzyme of glycogenesis?
A
glycogen synthase
20
Q
What is the rate determining enzyme of glycogenolysis?
A
glycogen phosphorylase
21
Q
What is the rate determining enzyme of HMP shunt?
A
G6PD
22
Q
What enhances activity of G6PD?
A
NADP+
23
Q
What decreases activity of G6PD?
A
NADPH
24
Q
What is the rate determining enzyme of de novo pyrimidine synthesis?
A
Carbamoyl phosphate synthetase II
25
What is the rate determining enzyme of de novo purine synthesis?
PRPP aminotransferase
26
What downregulates PRPP aminotransferase activity?
AMP IMP, GMP
27
What is the rate determining enzyme of urea cycle?
carbamoyl phosphate synthetase I
28
What is the rate determining enzyme of fatty acid synthesis?
acetyl coA carboxylase
29
What is the rate determining enzyme of fatty acid oxidation?
Carnitine acyltransferase I
30
What downregulates the activity of carnitine aceyltransferase I?
malonyl- CoA
31
What is the rate determining enzyme of ketogenesis?
HMG- CoA synthase
32
What is the rate determining enzyme of cholesterol synthesis?
HMG- CoA reductase
33
What type of processes is NAD+ used in?
CATABOLIC
34
What type of processes is NADPH used in?
Anabolic processes
35
What pathway produces NADPH?
HMP shunt
36
Where is glukokinase found?
LIVER
37
Where is hexokinase found?
most tissues except the liver and beta pancreatic cells
38
Which has a lower Km... hexokinase or glucokinase?
Hexokinase
39
Which has a higher Vmax...hexokinase or glucokinase?
Glucokinase
40
Which is inducable via insulin...hexokinase or glucokinase?
glucokinase
41
Which is inhibited by G6P...hexokinase or glucokinase?
Hexokinase
42
Which steps of glycolysis produces ATP?
Phosphogylcerte kinase
Pyruvate kinase
43
What inhibits pyruvate kinase?
Alanine and ATP
44
What enzyme is active in the fasting state...FBPase2 or PFK-2?
FBPase2--> converts F26BP back to F6P
45
What enzyme is active in the fed state... FBPase2 or PFK-2?
PFK-2--> converts F6P to F26BP
46
What are the 5 cofactors needed for pyruvate dehydrogenase complex?
B1, B2 B3, B5, Lipoic acid
47
What inhibits lipoic acid?
Arsenic
48
What is the treatment for pyruvate dehydrogenase complex deficiency?
increase intake of ketogenic nutrients (high fat or increased lysine and leucine)
49
What are the symptoms of pyruvate dehydrogenase complex deficiency?
Lactic acidosis, neuro defects and increased serum alanine
50
What 4 molecules does pyruvate lead to?
1- Alanine
2- Oxaloacetate
3- Acyl- CoA
4- Lactate
51
How many molecules of NADH, FADH2, CO2 and GTP produces per acetyl CoA?
NADH- 3
FADH2- 1
CO2- 2
GTP- 1
52
Order of molecules in the TCA cycle?
```
Citrate
Isocitrate
alpha- Ketogluteate
Succinyl- CoA
Succinate
Fumarate
Malate
Oxaloacetate
```
53
What complex in the ETC does FAD2 transfter electrons to?
Complex II (lower energy than NADH transfer (complex I)
54
What does rotenone block?
complex I
55
What does cyanide block?
Complex IV
56
What does antimycin A block?
Complex III
57
What does CO block?
complex IV
58
What does oligomycin blocl?
complex V
59
Name 2 uncoupling agents?
2,4- dinitrophenol
| Aspirin
60
Name the enzyme:
Pyruvate--> OAA
Pyruvate carboxylase
61
Name the enzyme:
OAA--> PEP
Phosphoenolpyruvvate carboxykinase
62
Name the enzyme:
F16BP--> F6P
F16BPase
63
What gluconeogenesis enzyme do muscles lack?
G6Pase
64
Deficiency in enzymes of gluconeogenesis results in...
hypoglycemia
65
Does HMP shunt produce ATP?
NO!!!
66
Which phase of the HMP shunt produces NADPH?
Oxidtive/ irreversible
67
Aside from producing NADPH, what are the other benefit if the HMP shunt?
Produces glycolytic intermediates and ribose for nucleotide synthesis
68
What enzyme is defieicny in essential fructosuria?
Fructokinase
AR
69
What enzyme is deficienct in fructose intolerance?
Aldolase B
AR
70
What accumulates in fructose intolerance?
F1P
this leads to decrease in phosphate (inhibition of glycogenolysis and gluconeogenesis)
71
What is the treatment for fructose intolerance?
Decrease intake fructose and sucrose
72
What enzyme is deficient in galactose deficiency?
Galactokinase (cannot convert galactose to Galactose 1 Phosphate)
73
What molecule increases in galactokinase deficiency?
Galactitol--> leads to infantile cataracts
74
What enzyme is deficient in classic galactosemia?
Galactose 1 phosphate uridyltransferase
75
What is the treatment for classic galactosemia?
exclude galactose and lactose from diet
76
What is sorbitol metabolized to?
Fructose
77
What enzyme produces sorbitol from glucose?
Aldolase reductase
78
What results from increased sorbitol wthin cells?
Osmotic damage (cataracts, retinopathy, peripheral neuropathy)
79
What is lactose metabolized into?
Glucose + galactose
80
Name the essential gluconeogenic amino acids?
Methionine
Valine
Histidine
81
What are the ketogenic essential amino acids?
Leucine
| Lysine
82
What are the essential amino acids that are both ketogenic and glucogenic?
Isoleucine
Phenylalanine
Threonine
Tryptophan
83
Which amino acids are negatively charged at body pH?
Aspartic acid
| Glutamic acid
84
Which amino acids are positively charged at the body pH?
Arginine
Lysine
Histidine
85
In the transport of ammonia...amino acids transfer their NH3 to what compound?
Glutamate which then transfers it to alanine
86
What is the cahill cycle?
Alaine (muscle)--> alanine (liver)--> pyruvate--> glucose (liver)--> glucose (muscle)--> pyruvate--> alanine (muscle)
87
What is the cori cycle?
Lactate (muscle--> lactate (liver)--> pyruvate--> glucose (liver)--> glucose (muscle)--> pyruvate --> lactate (muscle)
88
What is the most common deficiency of the urea cycle?
Ornithine transcarbamylase
89
NAG synthase deficiency affects which enzyme in the urea cycle?
Carbamoyl phosphate synthas I
90
Where are the enzymes carbamoyl phosphate synthase and ornithine transcarbamylase located?
Mitochondria
91
What amino acid is the backbone of urea?
Aspartate
92
What is the treatment for hyperammonemia?
Lactulose (ascidify the GI and trap NH4 for excretion
93
Tyrosine is a derivative of which amino acid?
phenylalanine
94
Niacin is a derivative of which amino acid?
Tryptophan
95
Serotonin is a derivative in which amino acid?
Tryptophan
96
Prophyrin and heme is a derivative of which amino acid?
Glycine
97
Glutathione is a derivative of which amino acids?
glutamate
98
Urea is a derivative of which amino acid?
arginine
99
NO is a derivative of which aminoa cid?
argining
100
NE/ DA/ Epi are derivatives of which amino acids?
Phenylalanine
101
Cofactor for dopamine--> NE?
vit C
102
Cofactor for NE--> Epi?
SAM
103
What phenylalanine derivative is melatin made from? What enzyme is responsible?
Made from DOPA
Tryosinase!
104
What is deficient in malignant PKU?
tetrahydrobiopterin cofactor
105
"musty body odor"
PKU
106
What enzyme is deficient in maple syrup urine disease?
alpha ketoacid dehydrogenase
107
"burnt sugar smelling urine"
Maple syrup urine disease
108
What amino acids are to be avoided in maple syrup urine disease?
isoleucine
Leucine
Valine
(branched amino acids)
109
"black urine when exposed to air"
Alkaptonuria
110
What is deficient in alkaptonuria?
Homogentisate oxidase
111
What pathway is defective in alkaptonura?
Tyrosine--> fumarate
112
What are the symptoms of homocystinuria?
1- intellectual disability
2- marfanoid habitus
3- lens sublixation
4- atherosclerosis
113
What amino acids cannot be reabsorbed in the PCT in cystinuria?
COLA
Cystine
Onithine
Lysine
Arginine
114
What type of receptor is the insulin receptor?
tyrosine kinase
115
What type of receptor is glucagon receptor?
increased cAMP--> increased PKA--> increased glycogen phosphoryalase kinase
116
What organ maintains blood sugar at appropriate levels?
Hepatocytes
117
What enzyme breaks alpha 1,4 linkages?
glycogen phosphorylase
118
What are the two debranching enzyme?
4alpha D glucanotransferase
alpha-1,6- glucosidase
119
Is glycogen phosphorylase active when it is dephosphorylated or phosphorylated?
Phosphorylated
120
What enzyme deficiency leads to severe fasting hypoglycemia, increased glycogen in liver, increased blood lactate, increased triglycerides, increased uric acid and hepatomegaly?
Glucose 6 phosphatase
| von gierke disease
121
What enzyme deficeicny leads to cardiomegaly, hypertrophic cardiomyopathy, exercise intolerance, systemic findings leading to early death?
Lysosomal alpha 1,4 glucosidase (acid maltase)
Pompe disease (type II)
122
What enzyme deficiency leads to is a milder form of type I glycogen storage disease with normal blood lactate levels?
Debranching enzyme (alpha 1,6 glucosidase
Cori Disease (type III)
123
What enzyme deficiency leads to increased glycogen storave in muscles but muscles cannot break it down leading to painful cramps, red urine after strenuous exercise?
Skeletal muscle glycogen phosphorylase (myophosphorylase)
McArdle disease (Type V)
124
How is McArdle disease treated?
B6
125
Deficient enzyme in fabry disease?
alpha- galactosidase A
126
Deficient enzyme in gaucher disease?
Glucocerebrosidase
127
Deficient enzyme in Niemann pick disease?
Shingomyelinase
128
Deficient enzyme in Tay sachs disease?
Heosaminidase A
129
Deficient enzyme in Krabbe disease?
Galactoerebrosidase
130
What enzyme is deficiient in Metachromatic leukodystrophy?
Arylsulfatase A
131
Deficient enzyme in Hurler syndroe?
alpha- L idurinidase
132
What is the deficient enzyme in Hunter syndrome?
Iduronate sulfatase
133
Name the lysosomal storage disease:
progressive neurodegeneration, foam cells, "cherry red" macula, hepatosplenomegaly
Neiman Pick
134
What builds up in nieman pick?
Sphingomyelin
135
Name the lysosomal storage disease:
central and peripheral demyelination with ataxia and dementia
Metachromatic leukodystrophy
136
What builds up in metachromatic leukodystrophy?
cerebroside sulfate
137
Name the lysosomal storage disease:
peripheral neuropathy of hands/ feet, angiokeratomas, CV and renal disease
Fabry disease
138
What builds up in fabry disease?
ceramide trihexoside
139
Name the lysosomal storage disease:
progressive neurodegeneration, delayed development, cherry red macula, lysosomes with onion skin
Tay sachs disease
140
What builds up in Tay sachs?
GM2 ganglioside
141
Name the lysosomal storage disease:
hepatosplenimegaly, pancytopenia, osteoporiss, necrosis of femus, lipid laden macrophages"
gaucher disease
142
What builds up in gaucher disease?
glucocerebroside
143
Name the lysosomal storage disease:
"peripheral neuropathy, developmental delay, optic atrophy, globoid cells
Krabbe disease
144
What builds up in krabbe disease?
Galactocerbroside
145
Name the lysosomal storage disease:
mild developmental delay, mild airway obstruction, mild hepatosplenomegaly, agressive behavior
hunter syndrome
146
Name the lysosomal storage disease:
developpmental delay, gargoylism, airway obstruction, corneal clouding, hepatosplenomegaly
Hurler syndrome
147
Inherited defect in transport of LCFAs in the mitochondria?
Systemic primary carnitine deficiency
148
Fatty acid synthesis requires the transport of _____ from the mitochondria to the cytosol.
Citrate
149
"inability to breakdown fatty acids into acetyl coA leading to accummulation of 8- 10 carbon fatty acyl in the blood"
Medium chain acyl CoA dehydrogenase deficiency
150
What leads to the production of ketone bodies?
Excess acetyl- CoA (glucose and FFA are shunted to ketone formation)
151
What maintains blood glucose levels in fasting states between meals?
hepatic glycogenolysis (major)
152
What maintains blood glucose levels during starvation between 1-3 days?
Hepatic glycogenolysis, adipose release of FFA, muscle and liver, hepatic gluconeogenesis from peripheral lactate and alanine
153
How long does it take for glycogen to be depleted?
1 day
154
What maintains blood glucose levels during starvation after day 3?
adipose stores (ketone bodies from acyl coA)
then after adipose stores are depleted protein degredation accelerates
155
What induces the enzyme HMG- CoA reductase?
insulin
156
What esterifies plasma cholesterol?
LCAT
157
What cells release VLDL?
Hepatocytes
158
What converts chylomiccrons to chylomicron remnants?
LPL
159
What converts VLDL--> IDL?
LPL
160
What converts IDL--> LDL?
Hepatic TG lipase
161
What cells release HDL?
Liver and intestine
162
What enzyme makes nascent HCL mature?
LCAT
163
What is the function of Mature HDL?
Transfer of cholesterol esers to VLDL, IDL, and LDL via CETP (cholesterol ester transfer protein)
164
What is the function of ApoE?
mediates remnant uptake
165
What molecules have ApoE?
```
Chylomicron
Chylomicron remnant
VLDL
IDL
HDL
```
166
What is the function of Apo A-I?
Activates LCAT
167
What molecules have Apo A-I?
Chylomicron
| HCL
168
What is the function of Apo C-II?
LPL cofactor
169
What molecules have Apo C-II?
Chylomicron
VLDL
HDL
170
What is the function of Apo B-48?
Mediates chylomicron secretion
171
What molecules have Apo B-48?
Chylomicron
| Chylomicron remnant
172
What is the function of Apo B-100?
Binds LDL receptor
173
What molecules have Apo B-100?
VLDL
IDL
LDL
174
Which molecule acts as a reserviour of Apo E and C-II?
HDL
175
What secretes HDL?
liver and intestine
176
Which familiar hyperlipidemia has absent LPL or altered Apo C-II?
Type I
177
Which familiar hyperlipidemia has absent or defective LDL receptor?
Type II
178
Which familial hyperlipidemia has hepatic overproduction of VLDL?
Type IV
