quiz 1.3 enzymes to metab Flashcards
(128 cards)
1
Q
conponents of holoenzyme
A
apoenzyme
cofactor
2
Q
name ng compelte na enzyme
A
holoenzyme
3
Q
organic cofactors can be ____ ______
A
prosthetic
2nd subtrate
4
Q
inorganic cofactors may be ____ ____
A
metallo enzyme
ion activators
5
Q
are cofactors heat stable or labile?
A
stable
6
Q
mechanism of action of cofactors
A
transfer and/or accept functional groups
7
Q
at the end of the rxn, coenzymes _______
A
revert to orig state
8
Q
coenzymes mostly derived from
A
vitamins
9
Q
NAD is derived from
A
nicotinic acid
10
Q
LIPOIC ACID is derived from
A
none
11
Q
pyridoxal phosphate is derived from
A
pyridoxine vit b5
12
Q
biochtin is derived from
A
biotin
13
Q
coenzymes not derived from vits
A
cenzyme q
tetrahydrobioprotein
lipoic acid
14
Q
classif of coenzymes
A
thos that tranfer H
those that transfer pther than H
15
Q
where is the active site of NAD
A
C4 or pyridine ring
16
Q
rxns involving NAD conezyme
A
LDH
malaye dehydrogenase
17
Q
rxns using NADP
A
G6PD reductive biosynthesis (NADPH)
18
Q
conezyme to succinic acid dehydrogenase is tightly bound thru
A
histidine
end product: fumaric acid
19
Q
rxns using FAD
A
succinic acid dehydr
fatty acylCoA
l-amino acid oxidase (FMN)
20
Q
absorbance for FAD/FADH2 and ano itsura
A
450nm
FAD intense color
FADH2 colorless
21
Q
the ubiquitous coenzyme
A
ubiquinone
22
Q
structure of uniquinone
A
has benzoquinone with side chains of repeating isoprenoid unis
23
Q
active sites of uniquinone
A
C1 and 4
24
Q
rxn where may ubiquinone
A
etc
25
absorbance ng ubiquinone and ano itsura
270-290nm
| oxidized form absorbs but disappears when reduced to hudroquinone form
26
conezyme fo the aromatic amino acids
tetrahydrobiopterin
27
thiamine pyrophosphate is derived from
thiamine B1
28
structure ng TPP
subsituted pyrimidine linked to thiazole ring with terminal phosphate
29
TTP requires
Mg++
30
TPP is ainactivated by
thiaminase found in raw fish
31
rxns using TPP
```
puruvic decarboxylase (nonoxid)
pyruvic dehydrogenase (oxid)
transkeolase
```
32
active site ng TPP
C2 ng thiazole ring
33
rxns using tetrahydrobiopterin
phenylalanine hydroxylase
| tryptophan hydroxylase
34
action of TPP
transfers binds aldehyde and ketol groups thru its carbanion center
35
2 forms of lipoic acid
cyclic/oxidized
| open:reduced
36
action of lipoic acid
sulfur group accepts and transfers acyl groups and H+
37
coenzyme A is derived from
pantothenic acid
38
active site g coenzyme A
ung sulfur sa dulo kung saan man un
39
structure ng bicytin
imidazolone ring fused with tetrahydrothiophene linked with valeric acid
40
biocytin is inactivated by
avidin in raw egg white
41
biocytin is derived from
nbiotin
42
mechanism or action ng biotin
carboxylation
43
ano ung mga may lysine na coenzyme
biocytin
| lipoic acid
44
rxns using biocytin
acetyl CoA carboxylase
pyruvate carbyxolase
propionyl carboxylase
methylmalonyl CoA carboxylase
45
2forms of pyridoxal phosphate
pyridoxal phosphate
| pyridoxamine phosphate
46
active site ng pyridoxal phosphate
aldehyde group at C4
47
pyridoxal phosphate reacts with alpha amino of amino acid substrate to form
schiff's base
48
three rxns that lyridoxal phosphate uses
transamination
decarboxation
racemization
49
pyridoxal phosphate is k inhibited by
isoniazid (INH) antiTb drug
50
pyridoxal phosphate binds to what of enzyme
lysine
51
how is schiff's base formed
pyridoxal bla reacts with alpha amino of amino acid substrate
52
rxns using pyridoxal bla
ALT AST
amino acid decarbo
amino acid racemase
53
transaminase mechanism
pyrudoxal bla > aldimine > ketimine > puridoxamine
54
me hanism where intermediate products are released even before all substrate added
ping pong
55
structure ng tetrahydro flouc acid
pterin rin linked to p-aminobenzoic acid bound to glutamic
56
avtive sites ng terragydrofolic nla
N5 ng pterin ring
| N10 ng PABA
57
conezyme inhibited by
folate antagonists
| like methotrexate and sulfonamides
58
rxns using tetrahydrofolate
serine hydroxymethyl transferase
thumidile synthetase
formyl synthetase
59
rxns that cobamide coenz use
racmization:isomerization
| transmethylation
60
2forms ng cobamide coenz
deoxyadenosyl conalamin
| methylcobalamin
61
rxns using cobamide coenz
methylmalonyl CoA mutase
| methionine synthase
62
active sites of FAD/FMN
N1 and 5
63
special com[onent of FAD/FMN
isoalloxazine ring
64
the coenzyme used in ETC
ubiquinone
65
a rxn using coenzyme A that activates palmitic acid for use
fatty acyl CoASH synthase
66
class 1 enzyme
oxidoreductases
67
class 2 enzyme
transferases
68
class 3 enzymes
hydrolases
69
class 4 enzymes
lyases
70
class 5 enzymes
isomerases
71
class 6 enzymes
ligases
72
refers to the protein part of the enzyme
apoenzyme
73
refers to the nonprotein part of the enzyme
cofactor/prosthetic group
74
the complete active enzyme is called
holoenzyme
75
in transferases, generally, the addition of _____ stimulates activity of receptor
phosphate
76
this is the regulation of attachment of whatever bla di ko na-note
covalent modification
77
what is the action of hydrolases
addition of water to break bonds
78
enzymes that are present at a constant amount in the cell
constitutive/housekeeping
79
enzymes that is induced by a particular substrate (genetic control)
inducible
80
model that states the binding site contains amino acid residues rearranged in complementary 3D surface which bind the substrate through various interactions
rigid tempate model (lokc and key)
81
who formulated lock and key model of active sites
fischer
82
who formulated the induced fit model of active sites
koshland
83
model that states that as the substrate binds, te enzyme undergoes a conformational change which positions the side chains of the amino acids in the active site and increases the number of boinding interactions
induced fit model
84
two perspectives that explain the action of enzymes
thermodynamic changes
| processes at the active site
85
difference in free energy between transition and substrate is called
Gibbs free energy of activation
86
diff. processes at the active site
```
proximity/orientation effect
desolvation effect
acid base catalysis
covalent catalysis
strain effect
metal coordination effect
```
87
the reacting groups are close enough or properly oriented as to favor formation of products
orientation/proximity effects
88
removal of water molecules accelerate enzymatic rxns
desolvation effects
89
removal of _______ accelerates enzymatic rxns
water
90
amino acid side chains on the enzyme acts as both proton acceptor and donor
acid base catalysis
91
covalent catalysis is aka
nucleophilic catalysis
92
nucelophilic side chains of amino acids on enzyme attacks nucleophilic parts of substrate and form covalent bonds
covalent catalysis/nucleophilic catalysis
93
conformational change subsequent to substerate binding may lead to distortion on some parts of the substrate
bond distortion/strain effects
94
etal ions acts as lewis acids which can accept electron pair to form a sigma bond
metal coordination effects
95
metalloenzymes are ______ bound
tightly
96
metal-activated enzymes are _____ bound
loosely
97
________________ always present cofactor metal ion
magnesium
98
the plot of pH vs. enzyme activity and temp vs activity gives a _____ shape
bell
ps. optimum pH and temp at peak
99
the enzymes are ______ beyond optimal pH and high temps
denatured
100
enzyme activity _______ proportionately to the conc. of th enzyme
increases
101
substrate concentration is shown in what graph
Michaelis Menten saturation graph
102
as subs. conc. increases, velocity increase only to a point when _________
enzyme is saturated with the substrate
103
a _____________ is obtained when activity of enzyme is plotted against substrate conc.
rectangular hyperbola
104
vmax _____ and km ______ with competitive inhibitors
normal; inc
105
vmax _____ and km ______ with noncompetitive inhibitors
dec; same
106
vmax _____ and km _____ with uncompetitive inhibitors
dec; dec
107
amount of activity that catalyzes the transformation of 1 umol of substrate per minute under specified conditions
IU
108
number of enzyme units per milligram of protein
specific activity
109
units of enzyme activity per umol pf enzyme
turnover rate or catalytic constant (kcat)
110
amount of enzyme activity that transform 1 mole of substrate per second
katal(kat)
111
specific rate constants of the reversible rxn
ks
112
ther eciprocal of the michaelis menten
lineweaver burke
113
slope in the lineweaver burke
km/vmax
114
is defined as the substrate concentration at 1/2 the maximum velocity
km
115
allosteric enzymes give _____ curves of V vs S
sigmoidal shaped
116
the concerted kung anuman to is aka
Monod-Wyman-Chageux
117
the sequential kung anuman to is aka
koshland-Nemethy-Filmer
118
model that describes allosteric transitions of proteins made up of identical subunits
Monod-Wyman-Chageux
119
This model of allosteric regulation holds that subunits are not connected in such a way that a conformational change in one induces a similar change in the others.
koshland-Nemethy-Filmer
120
binding of one ligand to one protomer can affect the binding of the same ligand to another protomer
homotropic interactiond
121
binding of one ligand affects the binding of a different ligand to another protomer
heterotropic interactions
122
means of enzyme regulation
allosteric effectors
reversible covalent modif.
stimulation and inhibition of control protein
proteolytic activation
123
inactive precursors of enzymes are called
zymogen/ptoenzymes
124
intracellular signaling that involves two mechanism
juxtacrine signaling
125
the two emchanism in juxtacrine signaling
gap juntion channels
| interaction of proteins expressed on the serface of sender cell
126
signal transduction that involves hormones secreted and long distance transport to target cells
endocrine signaling
127
transduction taht involves molecules secreted into its immediate or local environment
paracrine
128
a signaling specific to neurons
synaptic or neuronal signaling
