Bio Chem (Metabolism) Flashcards
1
Q
Glycolysis Tissue
A
all tissues
2
Q
Glycolysis Cellular compartment
A
cytosol
3
Q
Glycolysis substrate
A
glucose
4
Q
Glycolysis key enzymatic step
A
PFK-1* (rate limiting)
Hexokinase (found everywhere)
Glucokinase (pancreas and liver)
5
Q
Glycolysis product
A
pyruvate
6
Q
Glycolysis regulators
A
(+) insulin, Fructose 2,6-bisphosphate, AMP
(-) too much ATP or citrate
(-) ATP
7
Q
Glycolysis Cofactors
A
Mg
8
Q
Glycolysis Key intermediates
A
Glucose-6-phosphate can’t leave the cell once converted
9
Q
Glycolysis energy production
A
2 pyruvate
2 ATP
2 NADH
10
Q
Pyruvate oxidation tissue
A
tissue that have mitochondria and oxygen
11
Q
Pyruvate oxidation location
A
mitochondrial matrix
12
Q
Pyruvate oxidation substrate
A
pyruvate
13
Q
Pyruvate oxidation Cofactors and key enzyme
A
Pyruvate dehydrogenase needs
thiamine, niacin, riboflavin,
NAD, FAD, TPP, CoA, lipoic acid
14
Q
Pyruvate oxidation product
A
acetyl CoA
15
Q
Pyruvate oxidation regulation
A
(+) NAD, ADP
16
Q
Pyruvate oxidation energy production
A
2 acetyl CoA
2 NADH
2 NADH
17
Q
Anaerobic glycolysis tissue
A
tissue w/o oxygen
18
Q
Anaerobic glycolysis cellular compartment
A
cytosol
19
Q
Anaerobic glycolysis substrate
A
pyruvate
20
Q
Anaerobic glycolysis key enzyme step/cofactor
A
lactate dehydrogenase
NAD, FAD, TTP
21
Q
Anaerobic glycolysis product
A
lactate can be toxic if can’t eliminate
22
Q
Anaerobic glycolysis regulators
A
(+) NADH
23
Q
Anaerobic glycolysis energy generation
A
-NADH
24
Q
Krebs cycle tissue
A
all tissues, but liver is most significant
25
Krebs cycle cellular compartment
mitochondrial matrix
26
Krebs cycle substrate
acetyl CoA
27
Krebs cycle key enzyme/cofactor
isocitrate dehydrogenase (1st energy generating step) and alpha ketoglutarate dehydrogenase
AKDH needs same 5 cofactors as pyruvate dehydrogenase - NAD, FAD, TPP, CoA, lipoic acid
28
Krebs cycle product
Co2, NADH, FADH2, GTP
29
Krebs cycle regulation
(+) NAD, FAD, GDP
| (-) ATP, citrate
30
Krebs cycle energy productions
(+) 3 NADH
(+) 1 FADH
(+) 1 GTP
(run through twice for one molecule of glucose)
| (+) FADH
31
Glycogen synthesis tissue
liver
32
Glycogen synthesis cellular compartment
cytosol
33
Glycogen synthesis substrate
glucose
34
Glycogen synthesis key enzyme step
phosphoglucomutase (commits glucose to pathway)
glycogen synthase (links glucose molecules)
35
Glycogen synthesis product
glycogen
36
Glycogen synthesis regulation
(+) UTP
37
Glycogen synthesis key intermediates
UDP-glucose
38
Glycogen synthesis energy production
-1 ATP/glucose
39
Glycogenolysis tissues
liver, muscle
40
Pentose Phosphate Pathway/HMP Shunt tissues
liver, RBC mammary gland, adrenal cortex
41
Pentose Phosphate Pathway/HMP Shunt cellular component
cytosol
42
Pentose Phosphate Pathway/HMP Shunt substrate
glucose-6P
43
Pentose Phosphate Pathway/HMP Shunt key enzyme step
glucose-6P dehydrogenase (oxidative)
transktetolase (non-oxidative, requires TTP)
44
Pentose Phosphate Pathway/HMP Shunt product
NADPH, ribose sugars
45
Pentose Phosphate Pathway/HMP Shunt key intermediates
NADPH
46
Fatty Acid Synthesis tissues
liver, adipose, mammary glands, kidney
47
Fatty Acid Synthesis cellular component
cytosol (leaves mitochondria via citrate shuttle)
48
Fatty Acid Synthesis substrate
acetyl coA
49
Fatty Acid Synthesis key enzyme step
acetyl coA carboxylase (requires biotin)
fatty acid synthase (has B5 as part of structure)
50
Fatty Acid Synthesis product
palmitate
51
Fatty Acid Synthesis regulation
(+) insulin
52
Fatty Acid Synthesis key intermediates
malonyl coA
53
Fatty Acid Synthesis energy production
-1 ATP/malonyl CoA, -2 NADPH/malonyl CoA
54
Beta oxidation tissues
liver, muscle, kidney
55
Beta oxidation cellular component
mitochondria (peroxisome)
56
Beta oxidation substrate
fatty acyls
57
Beta oxidation key enzyme step
acetyl CoA synthase
58
Beta oxidation product
acetyl coA, NADH, FADH2
59
Beta oxidation regulation
(+) glucagon
60
Beta oxidation key intermediates
fatty acyl coA, fatty acyl carnitine
61
Beta oxidation energy production
16C saturated FA = 129 ATP (131 total - 2 ATP for activation)
62
ketogenesis tissue
liver
63
ketogenesis cellular component
mitochondrial matrix
64
ketogenesis substrate
acetyl coA
65
ketogenesis key enzyme step
HMG CoA synthase
66
ketogenesis product
beta-hydrozybuterate dehydrogenase, acetone, acetoacetate
67
ketogenesis regulation
(+) acetyl CoA
68
ketogenesis key intermediates
HMG CoA
69
ketogenesis energy production
-2 acetyl coA, -1 NADH
70
ketone degradation tissues
brain, skeletal muscle, heart muscle
| NOT liver
71
ketone degradation cellular component
mitochondrial matrix
72
ketone degradation substrate
products of ketogenesis
beta-hydrozybuterate dehydrogenase, acetone, acetoacetate
73
ketone degradation key enzyme step
beta-hydrozybuterate dehydrogenase
74
ketone degradation product
acetyl coA
75
ketone degradation key intermediates
HMG CoA
76
ketone degradation energy production
+2 acetyl coA, +1 NADH, -1 GTP
77
cholesterol synthesis tissue
liver
78
cholesterol synthesis cellular component
cytosol
79
cholesterol synthesis substrate
acetyl coA
80
cholesterol synthesis key enzyme step
HMG CoA reductase
81
cholesterol synthesis product
cholesterol
82
cholesterol synthesis regulation
(+) insulin
83
cholesterol synthesis key intermediates
HMG CoA, mevolonate --> CoQ
84
cholesterol synthesis energy production
lots
| body doesnt usually break it down for energy
85
urea cycle tissue
liver
86
urea cycle cellular component
cytosol, mithochondrial matrix
87
urea cycle substrate
NH4+, glucose, CO2, aspartate
88
urea cycle key enzyme step
CPS I (Rate limiting)
89
urea cycle product
urea
90
urea cycle regulation
(+) N-acetyl glutamate
91
urea cycle key intermediates
arginine, fumarate
92
urea cycle energy production
-2 ATP
93
gluconeogenesis tissues
liver, kidney, SI
94
gluconeogenesis cellular component
mitochondrial matrix, cytosol, ER
95
gluconeogenesis substrate
alanine (AA), lactate (AR), glycerol (Lipids)
96
gluconeogenesis key enzyme step
pyruvate carboxylase/ PEP carboxykinase
PFK I
G6P
97
gluconeogenesis product
glucose
98
gluconeogenesis regulation
(+) acetyl coA
(-) F26-bisP
| (-) F26-bisP
99
gluconeogenesis key intermediates
pyruvate, fructose-1,6-bisP, glocuose 6P
100
gluconeogenesis energy production
- 2 pyruvate
- 2 NADH
- 4 ATP
- 2 GTP
101
glycogenolysis tissues
liver, muscle
102
glycogenolysis cellular component
cytosol
103
glycogenolysis substrate
glycogen
104
glycogenolysis key enzyme step
glycogen phosphorylase
| requires biotin) (glucose 6P
105
glycogenolysis product
G6P or glucose (liver only)
106
glycogenolysis regulation
(+) AMP, cAMP
| (-) glucose
107
glycogenolysis key intermediates
G6P
108
what are the monosaccharides
glucose
fructose
galactose
mannose
109
what are the disaccharides
sucrose
lactose
maltose
isomaltose
110
what bond is on maltose
a1-4
111
what bond is on lactose
b1-4
lactase specific
112
what bond is on sucrose
a1-b2
113
what types of bonds are on glycogen
a1-4 (base chains)
| a1-6 (branch points)
114
what types of bonds are on cellulose
b1-4 (making it indigestible)
115
what is unique about the beta bond in lactose?
humans usually cant break down/digest beta bonds; but with lactose there is a specific lactase enzyme that allows us to
116
amylose vs amylopectin structure
amylose is unbranched, helix
| amylopectin branched chains of glucose
117
what are the polysaccharides
glycogen
inulin
cellulose
118
polysaccharides in carb absorption are broken down to monosaccharides by what
brush border enzymes
119
carb absorption; fructose is brought in via..
facilitated diffusion
120
what biochemical rxns take place in the mitochondria?
```
krebs cycle
fatty acid oxidation
formation of acetyl coA
part of urea cycle
part of gluconeogenesis
```
121
what biochemical rxns take place in the golgi?
synthesis and packaging of complex molecules including glycolipis, glycoproteins, and lipoproteins
122
what biochemical rxns take place in the cytosol
```
glycolysis
HMP shunt
protein synthesis
fatty acid synthesis
part of urea cycle
part of gluconeogenesis
```
123
what biochemical rxns take place in the lysosomes
degradation of complex macromolecules
124
what biochemical rxns take place in the nucleus
DNA and RNA synthesis
125
most ATP is formed in which cellular component?
mitochondria
126
why break down proteins, carbs, and fats into acetyl-coA (C2) in the TCA/krebs/citric acid acycle?
to link them with oxaloacetate (C4) and create citric acid/citrate
127
vitamins with role in TCA
thiamin (B1)
riboflavin (B2)
niacin (B3)
pantothenic acid (B5)
128
how is H oxidation accomplished in ox-phos?
by splitting hydrogen atom into H+ ion and free electron
129
pathologies associated with ox phos of electron transport chain
uncoupling
inhibition = blocking respiratory chain at places other that ADP+P posiotion
poisons, insecticids, antibiotics, barbituates
130
where does the electron transport chain take place?
INNER membrane of mitochondria
131
glycolysis aerobic/anaerobic
can occur under both
aerobic glycolysis ends at pyruvate
anaeorbic ends at lactate (less energy produced)
132
hexokinase is found mainly in what tissue
muscle cells
133
glucokinase is found mainly in what tissue
liver cells
134
what is the major controller of liver glycogen metabolism
concentration of phosphorylase-a
135
increased cAMP has what effect on
glycogenesis
glycogenolysis
SLOWS glycogenesis (inactivation of glycogen synthase)
MORE glycogenolysis (activation of phosphorylase)
136
HMP shunt primary functions
alternative route for glucose metbolism
- generates NADPH
- provides ribose residues
137
HMP shunt ATP generation
NONE
138
what are eicosanoids
biologically active 20 carbon fatty acids that give rise to cytokines/prostanoids (prostaglandins, thromboxanes, leukotrienes)
139
of the 3 series of eicosanoids, which are completely essential and which are conditionally essential?
linoleic (omega 6) and alpha linoleic (omega 3) fatty acids are completely essential
arachodonate is conditionally essential
140
role of eicosanoids
gives rise to individual sets of prosaglandin, leukotriene, and thromboxane (PG-1, LK-1, TX-1, PG-2, LK-2, etc..) to work in concert to create inflammatory and anti-inflammatory balance
141
what are the three series of eicosanoids
series 1: linoleic acid (omega 6)
series 2: arachadonic acid
series 3: alpha-linolenic acid (omega 3)
142
which series of eicosanoid is pro-inflammatory
series 2: arachadonic acid
143
what enzyme breaks down arachadonate out of membrane phospholipid > arachadonic acid
PLA-2 (phospholipase A2)
144
what enzyme converts arachadonic acid > leukotrienes
lipoxygenase
145
what enzyme converts arachadonic acid > prostaglandins/thromboxanes
cyclooxygenase
146
what are the essential amino acids
Three Liars, Val, Lucy, and Me, Tripped and Fell in His Isolation Tank
```
threonine
lysine
valine
leucine
methionine
tryptophan
arginine
phenylalanine
histidine
isoleucine
```
147
non-essential amino acids
Almost All Girls Go Crazy After Getting Taken Prom Shopping
```
alanine
aspartate
glutamate
glycine
cysteine
asparginine
glutamine
tyrosine
proline
serine
```
148
what makes up the tripeptide glutathione and which is the rate limiting AA for formation
glutamic acid/glutamine
cysteine (RL)
glycine
149
what is a zymogen
| give an example
inactive precursor of an active enzyme
Ex:
zymogen: trypsinogen
enzyme: trypsin
150
how do enzymes speed up thermodynamically favorable reactions
lower energy of activation by binding to a SUBSTRATE
| an enzyme is NOT part of any product
151
enzyme activity (reaction rate) is affected by:
temp
| pH
152
what are co-factors
small molecular weight substances (B vitamins and trace minerals) that are neede to help some enzymes react
typically the cofactor is part of the substrate binding site, on the enzyme
153
enzymes; difference between competitive vs non-competitive inhibition
competitive: binds at substrate binding site
non-competitive: binds to non-substrate site
154
products of HMP shunt are important in which processes
nucleic acid synthesis
steroid synthesis
hepatic phase I detox
155
which part of the urea cycle occurs in the mitochondria?
NH4+CO2 > carbamoyl phosphatase (CP)
CP > L-citrulline
156
which part of the urea cycle occurs in the cytosol?
series of transaminations resulting in L-arginine going to urea + L-ornithine
157
L amino acids are actively transferred across the intestines with the help of what?
vitamin B6
158
what cofactor is necessary for alanine aminotransferase rxns?
vit B6 derivative
159
for the following AA name the alpha-keto acid and enzyme for its conversion
alanine
glutamate
aspartate
alanine > (ALT) > pyruvate
glutamate > alpha ketoglutarate
aspartate > (AST) > oxaloacetate
160
What is the enzyme produced by the brush border and pancreas, and is responsible for the cleaving of single amino acids off of the carboxy end of the peptides?
Carboxypeptidase
161
Which enzyme is responsible for converting IMP and GMP into their nucleoside forms?
5’-nucleotidase
162
what is choleterol an important precursor for?
bile acids
steroid hormones
vitamin D
163
what metabolic process is Carnitine Acyl transferase involved in
lipolysis
164
what metabolic process is Acetyl CoA carboxylase involved in
lipid synthesis
165
what metabolic process is HMG CoA reductase involved in
cholesterol synthesis
166
what metabolic process is HMG CoA synthase involved in
ketogenesis
167
What is the rate-limiting enzyme involved in steroid synthesis
20,22-desmolase
168
what does the enzyme hydrolase do
adds H2O to break bonds (hydrolysis)
169
what does the enzyme aldolase do
cleaves C-C bonds to form aldehydes
170
what does the enzyme dehydrogenase do
removes H from substrate
171
what does the enzyme hydratase do
adds H2O to C-C bonds without breaking bond
can also remove H2O to create double bond
172
what does the enzyme isomerase do
converts between isomers
cis/trans, D/L, aldolase/ketolase
173
what does the enzyme esterase do
hydrolyzes ester linkages to form an alcohol and acid
174
first step of liver detox pathway
phase 1 - hydroxylating cytochrome 450 system; makes fat soluble compounds water soluble
CYP450
(-OH added)
175
second step of liver detox pathway
phase 2 - enzymatic conjugation
takes water soluble/polar intermediates and adds an "anchor" by conjugating them with amino acids
176
last step of liver detox pathway
excretion
bile
serum > urine
177
regulatory enzyme for lipolysis
carnitine acyltransferase
178
regulatory enzyme for fat mobilization
hormone sensitive lipase
179
regulatory enzyme for lipid synthesis
acetyl-CoA carboxylase
180
regulatory enzyme for cholesterol synthesis
HMG CoA reductase
181
regulatory enzyme for pentose phosphate shunt
G6P dehydrogenase
182
regulatory enzyme for ketone body synthesis
HMG CoA synthase
183
regulatory enzyme for purine synthesis
amidotransferase
184
preferred nutrient of brain for
normal:
prolonged fast:
normal: glucose
fast: ketone bodies, glucose
185
preferred nutrient of muscle for
normal:
prolonged fast:
normal:
rest - fatty acids
exercise - glucose
fast: fatty acids
186
preferred nutrient of heart for
normal:
prolonged fast:
"takes anything"
fatty acids, ketone bodies, lactate, glucose for normal and fast
187
preferred nutrient of erythrocytes for
normal:
prolonged fast:
glucose for both normal and fasting
188
what do kinases do?
phosphorylate - take a phosphate group from high energy substrate (ATP) > ADP
adding a phosphate group (kinase is included in word, "hexokinase") uses ATP, removing one (kinase separate from name "pyruvate kinase") gains ATP
189
what is the purpose of glycolysis?
converting sugar to energy
190
what are the processes involving in aerobic respiration?
glycolysis
pyruvate dehydrogenase
TCA cycle
ETC
glycogenolysis
glycogenesis
gluconeogenesis
191
what are the fates of pyruvate?
pyruvate >
> actetyl CoA (pyruvate oxidation) ** most energy generating path
> lactate (anaerobic glycolysis/lactic acid cycle)
> alanine
> oxaloacetate
191
what five cofactors are required for the pyruvate dehydrogenase enzyme complex involved in conversion of pyruvate to Acetyl CoA to prep for entry to TCA cycle?
thiamine pyrophosphate (B1)
lipoic acid
CoA (B5; pantothenic acid)
FAD (B2, riboflavin)
NAD+ (B3, niacin)
"The Lovely Co-enzymes For Nerds"
192
what is the purpose of anaerobic glycolysis? when would this occur?
to regenerate NAD+
cells without mitochondria (RBCs) or anaerobic conditions of skeletal mm
193
which complex of the ETC involves NADH? which involves FADH?
complex 1 - NADH
complex 2 - FADH2
194
what cofactor is involved with complex 3 of the ETC?
CoQ10
195
how many ATP is 1 NADH?
| NPLEX RULES
3
196
how many ATP is 1 FADH?
| NPLEX RULES
2
197
1 molecule of glucose =
| NPLEX RULES
glycolysis: 2 NADH, 2 ATP
pyruvate: 2 NADH
TCA: 6 NADH, 2 GTP, 2 FADH
= 38 ATP (36-38 based on shuttles)
198
what are the intermediates of the krebs cycle?
Citrate
Is (isocitrate)
Krebs (aKG)
Starting (succinyl coA)
Substrate (succinate)
For (fumarate)
Making (malate)
Oxaloacetate
199
what are the shuttles that take biproducts into mitochodria?
malate shuttle (kidney, liver, heart)
gkycerol-3-phosphate shuttle (brain, skeletal muscle)
200
what does the malate shuttle do?
when there is high NADH:NAD in cytosol > moves NADH WITH concentration gradient
201
what does the glycerol 3 phosphate shuttle do?
when there is low NADH:NAD in cytosol > moves NADH AGAINST concentration gradient
(requires energy; -1 NADH, +1 FADH2; net loss of 1 ATP per pyruvate molecule >>> hence why 2 less ATP)
202
what bonds can amylase break?
alpha 1-4 (CAN'T break down alpha 1-6 in complex carbs)
203
what is gluconeogenesis?
production of glucose from NEW (non-carb) sources:
pyruvate, AAs, fats, glycerol, lactic acid
204
where in the body does gluconeogenesis occur?
liver
kidney (PCT)
small amounts in intestines
205
what transporter brings glucose into the liver? what about kidneys?
GLUT-2 (liver)
GLUT-3 (kidney)
206
key cofactor for hexokinase/glucokinase in glycolysis
magnesium
207
cofactors for LDH in anaerobic glycolysis
TPP (b1)
NAD (b3, niacin)
FAD (b2, riobflavin)
208
cofactors for isocitrate DH / aKG DH in TCA
same as PDH (TPP, NAD, FAD, Lipoic acid, CoA)
209
main purpose of PPP/HMP Shunt
produce NADPH
210
what main processes could Acetyl coA do?
- go into krebs cycle and make energy
- go into fatty acid synthesis
- go into cholesterol cynthesis
211
what molecules serve as "shunts" and move processes in and out of structures
fatty acyl carnitine
citrate
212
steroisomers
- enantiomers: mirror image (D vs L)
- diasteromers: non, mirror image
- epimer: differ at one carbon
- anomers: cyclized structures only, A or B
213
what are the monosaccharides
glucose
mannose
galactose
fructose
214
what are the digestible disaccharides
- sucrose (glucose-fructose)
- lactose (glucose-galactose)
- maltose (glucose-glucose)
215
GLUT 1
erythrocyte
blood --- barrier
- brain
- retinal
- placental
- testis
216
GLUT 2
liver
kidney
pancreatic beta cells
serosal surface of intestinal mucosa cells
217
GLUT 3
brain (neurons)
218
GLUT 4
adipose tissue
skeletal muscle
heart muscle
insulin sensitive
219
GLUT 5
intestinal epithelium
spermatozoa
actually a fructose transporter
220
when do we want glycogen metabolism to occur? where?
when we want to store glucose or use reserves
cytosol
221
rate limiting step for glycogenolysis and its cofactor
glycogen phosphorylase
pyridoxal-5-phosphate (B6)
222
rate limiting step for glycogenesis
glycogen synthase
223
upregulation for glucose (gluconeogenesis OR glycogenolysis)
glucagon (liver only)
epinephrine
GTP
224
upregulation for glycogen
insulin; will encourage glucose uptake into cells and glycogen formation
225
rate limiting step of glycolysis and what upregulates it?
phosphofructokinase
- amp
- h+
- fruc 2,6 biphos (inc with insulin)
226
fates of pyruvate
- pyruvate ox (mitochondrial matrix)
- anaerobic glycolysis (cytosol)
227
purpose of anerobic glycolysis
regenerate NAD+
cystol
cells without mitochondria (RBCs)
anaerobic conditions (skeletal muscle)
228
sources of acetyl coA for TCA cycle
- fatty acid (palmitate) beta ox
- ketone body (acetoacetate) metabolism
- glucose
- pyruvate oxidation
- amino acid (alanine) catabolism
- ethanol metabolism
229
ketogenic vs glucogenic AA function
ketogenic AA can be ox to form acetyl coA for ketone body genesis during ketosis
purely keto: lysine and leucine
both: PITTT, phenylalanine, isoleucine, tyrosine, tryptophan, threonine
all others glucogenic (converted > glucose during gluconeogenesis)
230
TCA rate limiting step
isocitrate dehydrogenase
231
232
ETC location
inner mitochondrial membrane
233
ETC complexes and inhibiting factors
- complex I: - by rotenone
- complex II (succinate dehydrogenase)
- complex III: - by antimycin A
- complex IV: - by cyanide, CO
- complex V: - by oligomycin
234
insulin secretion
secretion is
- stim by glucose
- inhibited by epi
235
insulin function relationship to metabolism
causes glucose uptake, synthesis of
- glycogen
- protein
- fat
236
what enzyme is involved in insulin receptor activation
receptor tyrosine kinase >phosphorylates insulin receptor and IRS
237
insulin v glucagon cells
insulin beta cells
glucagon alpha cells
238
glucagon secretion
stim by low glucose or inc epi
inh by insulin
239
what enzyme is involves in glucagon activation
adenylate cyclase > protein kinase
240
fructose metabolism
- mostly liver (sometimes small int or kidney)
- enters cells via facilitated diffusion
- insulin independent
- rate limiting step: aldolase B
241
def of aldolase B vs def of fructokinase
def aldolase B:fructose intolerance
def fructokinase: fructosuria
