Enzymes Flashcards
(229 cards)
0
Q
Abnormal large amount of enzymes in serum are used clinically as evidence of?
A
Organ damage
1
Q
When bind tightly to the enzyme, the coenzyme is called
A
Prosthetic group
2
Q
Water free cavity
A
Active site
3
Q
Inactive enzyme precursor. Coagulation factors and digestive enzyme
A
Proenzyme or zymogen
4
Q
Where the substrates bind and undergo a chemical reaction
A
Active site
5
Q
Active substance formed by a combination of a coenzymes and an apoenzymes
A
Holoenzyme
6
Q
Binds regulatory molecules
A
Allosteric site
7
Q
Substance acted upon enzyme, specific for each enzyme
A
Substrates
8
Q
Promote change in shape
A
Allosteric site
9
Q
Specific biologic proteins that catalyze biochemical reactions without altering the equilibrium point of the reaction or being consumed or changed in composition
A
Enzymes
10
Q
Represents the subclass to which the enzyme is assigned
A
Second and third digits
11
Q
Serial number that is specific to each enzyme in a subclass
A
Final and fourth number
12
Q
Helper molecules, nonprotein substance added in the enzyme substance complex to manifest the enzyme activity
A
Cofactors
13
Q
Places the enzyme in its classification
A
First digit
14
Q
Catalyze the hydrolysis of various bonds.
Splitting of a bond by addition of water
A
Hydrolases
15
Q
Catalyze the interconversion of geometric, optical or positional isomers
A
Isomerase
16
Q
Protein portion of enzyme, subject to denaturation, in enzyme losses activity
A
Apoenzyme
17
Q
Physical binding of a substrate to the active site of an enzyme
A
ES complex
18
Q
Catalyze an oxidation reduction reaction between two substrates
A
Oxidoreductase
19
Q
Catalyze the joining of two substrate molecules, coupled with breaking of the pyrophosphate bond in adenosine triphosphate or a similar compound
A
Ligases
20
Q
Enzymes combined with only one substrate and catalyzes only one reaction
A
Absolute specificity
21
Q
They combine with all the substrates containing a particular chemical group
A
Group specificity
22
Q
Reaction rate is directly proportional to substrate concentration
A
First order kinetics
23
Q
Excess energy
The energy required to raise all molecules in 1mol of a compound at a certain temperature to the transition state at the peak of energy barrier
A
Activation energy
24
Specific to chemical bonds
Bond specificity
25
pH range wherein most physiologic reactions occur
7-8
26
Enzymes that predominantly combine with only one optical isomer of certain compound
Stereoisomeric specificity
27
Only a fixed number of substrates is converted to product per second
Zero order kinetics
28
Inactivation temperature of enzymes
60-65C
29
Nonprotein entities that must bind to particular enzymes before a reaction occurs
Cofactor
30
Optimal pH is controlled by means of appropriate
Buffer solution
31
Catalyze the transfer of a group other than hydrogen from one substrate to another
Transferase
32
Incubation temperature
+/-1C
33
For every 10C increase in temperature, there will be two fold increase in enzymatic activity
Temperature coefficient
34
Alter the spatial configuration of the enzyme for proper substrate binding, linking substrate to the enzyme or coenzyme
Activators
35
Binds an enzyme at a place other than the active site but instead prevent all enzymatic activity by binding to all allosteric site located elsewhere on the enzyme
Noncompetitive inhibitor
36
Catalyze the removal of groups from substrates without hydrolysis.
The product contains double bonds
Lyases
37
Second substrate
Coenzyme
38
Physically bind to the active site of an enzyme and compete with the substrate for the active site
Competitive inhibitor
39
Appear in the serum following cellular injury
Enzymes
40
Enzymes are measured in terms of?
Change in:
Substrate concentration
Product concentration
Coenzyme concentration
41
Results in permanent loss or enzymatic activity
Permanent binding
42
Results from a change in the shape of the active site when an inhibitor binds to an allosteric site
Allosteric inhibitor
43
Reaction rate depends only on enzyme concentration
Zero order kinetics
44
Enzymes are active at what temperatures?
25, 30, and 37C
45
Binds to the enzyme substrate complex. Does not yield products
Uncompetitive inhibitor
46
Theory wherein based on the shape of the key must fit into the lock
Lock and key theory
47
The reactants are combined, the reaction proceeds for designated time, the reaction stopped and a measurement of the amount of reaction that has occurred is made
Fixed time method
48
An increase in the concentration of substrate molecules will result to the increase in the likelihood of the active site that will be filled by the substrates instead of inhibitors
Reversible competition
49
An organic factor
Coenzyme
50
Based on the substrate binding to the active site of the enzyme.
Induced fit theory
51
Coenzyme frequently measured in the lab
NADH
52
Multiple measurements of the absorbance changed are made during the reaction
Continuous monitoring
53
Results when binding of an activator molecule to an allosteric site caused a change in the active site that makes it capable a binding a substrate
Excitory allosteric inhibitor
54
Enzyme concentration are always performed in?
Zero order kinetics
55
Similar enzymatic activity but differ in physical, biochemical and immunologic characteristics
Isoenzyme
56
Increasing its concentration will increase the velocity of an enzymatic reaction.
Essential for complete enzymatic activity
Coenzyme
57
The reaction is assumed to be linear over the reaction time
Fixed time method
58
As the enzyme binds to the substrate the shape of the active site conforms precisely to the shape of the substrate
Induced fit
59
Convenient method of an enzyme quantitation is measurement of its?
Catalytic activity
60
Optimum temperature of enzymatic activity
37C
61
More advantageous over fixed time method because the linearity of the reaction may be more adequately verified
Continuous monitoring
62
Acid phosphatase is seen in
Prostatic carcinoma
63
Alanine transferase is seen in
Hepatic disorder
64
Alkaline phosphatase is seen in
Hepatic disorder
| Bone disorder
65
GGT in
Hepatic disorder
67
Lactate dehydrogenase
Myocardial infarction
Hepatic disorder
Hemolysis
Carcinoma
68
Amylase in
Acute pancreatitis
69
Lipase in
Acute pancreatitis
71
Trypsin in
Acute pancreatitis
72
Aspartate aminotransferase
Myocardial infarction
Hepatic disorder
Skeletal muscle disorder
73
Myocardial infarction increase in what enzyme?
AST
CK
LD
75
Hepatic disorder increase in
```
ALT
ALP
AST
GGT
LD
```
76
Chymotrypsin in
Chronic pancreatitis insufficiency
77
Skeletal muscle disorder increase in
AST
| CK
78
Acute pancreatitis increase in
AMY
LPS
Trypsin
79
Chronic pancreatitis insufficiency increase in?
Chymotrypsin
| Elastase 1
80
Generally associated with ATP regeneration in contractile or transport system
CK
81
CK major sources
Skeletal, muscle and brain tissue
82
Predominant function occurs in muscle cells, where it is involved in the storage of high energy creatine phosphate
CK
83
CK level is considered as sensitive indicator of?
Acute myocardial infarction
| Duchenne type
84
CK is a dimeric molecule with small molecular size composed of pair of two different monomers called
M and B
85
This is known to increase CK <5x URL
Intramuscular injection
86
The dominant isoenzyme of CK found in brain, intestine and smooth muscle
CK-BB
87
Highest concentration of CK BB is seen in
CNS
GIT
Uterus during pregnancy
88
Useful tumor associated marker
CK BB
89
CK isoenzyme that Migrate fastest
CK BB
| CK-1
90
Serves as buffer
| Component of CK reagent
Imidazole
92
Creatine kinase in
Myocardial infarction
| Skeletal muscle disorder
93
The only tissue from which CK MB enters the serum in significant quantities
Myocardium
94
Measures decrease in absorbance at 340nm with optimum pH oh 9. CK method
Tanser-Gilbarg assay
| Forward or direct method
95
Potent inhibitor
Urate and cystein
97
For the detection of myocardial damage
CK MB
98
Elastase-1 in
Chronic pancreatitis insufficiency
99
Forward method is coupled with
Pyruvate kinase-LD-NADH system
100
CK is sensitive with?
Light and pH
101
CK MB begin to rise in? Peak? Normalize?
Rise:4-8 hrs
Peak:12-24hrs
Normalize:48-72hrs
102
Released after cell lysis interferes with CK assay particularly with hemolysis of >320mg/dL
Adenylate kinase
103
CK MB is not elevated in?
Angina
104
Not usually measurable when tissue damage occurs
CK BB
105
With this amount, CK MB is considered as the most sensitive indicator of myocardial damage
>6% of total CK
106
Both abundantly present in cardiac and skeletal muscle
CK MM
107
Pyridoxal phosphate functions as coenzyme
AST
108
Most commonly performed
2-6x faster
Optimal pH of 6.8
CK method
Oliver rosalki
| Reverse indirect method
109
EC code of CK
EC 2.7.3.2
110
Involved in the transfer of an amino group between aspartate and alpha keto acids with the formation of oxaloacetate and glutamate
AST
111
Major source of AST
Cardiac tissue
Liver
Skeletal muscle
112
AST is for the evaluation of
Myocardial infarction
Skeletal muscle involvement
Hepatocellular disorder
113
In AMI, AST begin to rise? Peak? Normalize?
Rise:6-8hrs
Peak:24hrs
Normalize:within 5 days
114
Routinely used method for AST.
| pH 7.5; 340nm
Karmen method
115
Karmeyhod used this indicator reagent to monitor the change in absorbance
Malate dehydrogenase
116
Two enzyme fraction of AST
Cytoplasm and mitochondrial
117
Predominant AST isoenzyme occurring in serum
Cytoplasmic isoenzyme
118
EC code of LD
EC1.1.1.27
119
Enzyme that catalyzes the interconversion of lactic and pyruvic acid
LD
120
LD 1 contain high levels of?
RBC and cardiac tissue
121
EC code of AST
EC 2.6.1.1
122
Hydrogen transfer enzyme that uses the coenzyme NAD+
LD
123
Markedly increased in hepatic carcinoma and toxic hepatitis
LD5
124
Two different polypeptide chain in LD
H and M
125
In AMI, LD levels rise? Peak? Normalize?
Rise:12-24hrs
Peak:48-72hrs
Remain elevated for 10days
127
Major isoenzyme in the sera of healthy individuals
LD2
128
LD isoenzyme. More abundant in skeletal muscle
LD5
129
G6PD in
Drug induced hemolytic anemia
130
Alcohol dehydrogenase LD isoenzyme
LD6
131
LD6 is elevated in
Drug hepatotoxicity and obstructive jaundice
132
LD6 is present in patients with
Arteriosclerosis
133
LD1 prefers what method? How bout Ld5?
LD1-forward
| LD5-reverse
134
Screening test for AMI.
| Small heme protein found in skeletal and cardiac muscle
Myoglobin
135
Highest level of LD are seen in
Pernicious anemia
| Hemolytic disorder
136
Reverse method is coupled with
Hexokinase-G6PD-NADP system
137
Substrate that the represent LD1 activity of total LD
Alpha hydroxybutyrate
138
Marker for angina and early detector for AMI
Myoglobin
139
Method in myoglobin:
| Based on latex enhanced immuno turbidimetric method
Diazyme myoglobin assay
140
Method in LD.
pH7.2
2x faster as the forwad
Wroblenski La due
| Reverse
141
Complex of three proteins that bind to the thin filaments of cardiac muscle
Troponins
142
Most important marker of cardiac injury
Troponin
143
Specific for heart muscle
Valuable tool in diagnosis of AMI
Binds the troponin complex to tropomyosin
Troponin T
144
TnI in AMI
Onset:3-6hrs
Peak:12-18hrs
Normalize:5-10days
145
Liver specific enzyme
ALT
146
EC code of ALT
EC2.6.1.2
147
Regulate the calcium dependent interaction of myosin head with actin filament during striated muscle contraction
Cardiac troponin
148
Responsible for transmitting calcium signal that triggers muscle contraction
Troponin
149
Troponin is gold standard in?
Acute coronary syndrome
150
Inhibits the binding of actin and myosin
| Very sensitive indicator
Troponin I
151
Troponin T in AMI
Onset:3-4hrs
Peak:10-24hrs
Normalize:7days
152
Significant in the evaluation of hepatic disorders. Monitors the course of hepatitis treatment and effect of drug therapy
ALT
153
Nonspecific enzyme capable of reacting with many different substrates
Alkaline phosphatase
154
Alkaline phosphatase EC code
EC3.1.3.1
155
Functions to liberate inorganic phosphate form an organic phosphate ester with the concomitant production of an alcohol
Alkaline phosphatase
156
In normal sera, ALP was derived from?
Liver and bone
157
This blood group increases intestinal ALP after consumption of a fatty meal
B and O blood group
158
ALP require this ion as an activator
Mg2+
159
Isoenzyme of ALP that migrate fastest? Slowest?
Fastest-liver ALP
| Slowest-intestinal ALP
160
Isoenzyme of ALP that is most heat stable? Heat Labile?
Stable-placental ALP
| Labile-bone ALP
161
Total ALP increased, what is the isoenzyme that is most frequently elevated? Associated disease?
Liver ALP
| Obstructive jaundice
162
Bone ALP increased in?
Pagets disease or osteitis deformans
163
ALP levels are significantly decrease in ?
Hypophosphatasia
164
Isoenzyme characterized by the ectopic production of an enzyme by malignant tissue
Regan isoenzyme
165
Detected in lung, breast, ovarian and gynecologic cancers
regan isoenzyme
166
Regan is co migrator of?
Bone ALP
167
Regan is inhibited by?
Phenylalanine
168
Useful in monitoring the effects of therapy because it disappear on successful treatment
Regan isoenzyme
169
Detected in adenocarcinoma of the pancreas and bile duct, pleural cancers
Nagao isoenzyme
170
Nagao is inhibited by?
Phenylalanine and L-leucin
171
Heat stability test of ALP is performed at?
56C for 10-15mins
172
Catalyze the transfer of glutamyl groups between peptides or amino acids through linkage at a gamma carboxyl group
GGT
173
GGT EC code
Ec2.3.2.1
174
Elevated among individuals undergoing warfarin, phenobarbital, and phenytoin therapy
GGT
175
Cholinesterase EC code
EC3.1.1.7
176
Cholinesterase is marker of?
Insecticide and pesticides poisoning
177
Used to monitor the effect of muscle relaxants after surgery
Cholinesterase
178
Useful in differentiating the source of an ALP level
GGT
179
GGT is elevated in
Biliary tract obstruction
180
GGT is a sensitive indicator of?
Alcoholism
181
Involved in:
Peptide and protein synthesis
Regulation of glutathione levels
Transport of amino acid across cell membrane
GGT
182
Index of parenchymal function
Cholinesterase
183
Added to the reverse method to inhibit AK
Adenosine monophosphate
184
In AMI: myoglobin onset? Peak? Normalize?
Onset:1-3hrs
Peak:5-12hrs
Normalize:18-30hrs
185
Zinc containing enzyme that is part of the glycolytic pathway and is found virtually all cells in the body
LD
186
Method in LD determination. Most commonly used
Produces positive rate NADH
Not affected by product inhibition
Wacker method
| Forward method
187
Tissue sources of LD
LD1&2-heart, RBC, kidneys
LD3-lungs, pancreas, spleen
LD4&5-skeletal muscles, liver, intestines
189
Major isoenzyme in the sera of a healthy person
CK MM
190
Catalyzes the breakdown of starch and glycogen
Amylase
191
Addition of these substances will make assay more sensitive and specific for AP detection
Colipase and bile salts
192
Measures amylase activity by following the decreases in substrate in substance concentration. Degradation of starch
Amyloclastic
193
The most predominant pancreatic amylase isoenzyme in acute pancreatitis
P3
194
Condition when amylase combined with immunoglobulin to form a complex that is too large to be filtered by the glomerulus
Macroamylasemia
195
Measures the amount of reducing sugars produced by the hydrolysis of starch
Measures the appearance of product
Saccharogenic
196
Major tissue sources of amylase
Acinar cells of pancreas and salivary glands
197
Amylase EC code
EC3.2.1.1
198
Stages in prostatic carcinoma
A and B- malignant tumor
C- prostate in pelvic area
D-metastasized tumor
199
Measures disappearance of starch
Amyloclastic
200
Amylase requires these ions for activation
Calcium and chloride ions
201
Smallest enzyme. Normally filtered by the glomerulus and also appears in the urine
Amylase
202
Enzyme that hydrolyzes the ester linkages of fats to produce alcohol and fatty acids
Lipase
203
Measures amylase activity by the increase in color intensity of the soluble dye substrate solution produced in the reaction
Chromogenic
204
Method for lipase: used an olive oil as a substrate and measured the liberated fatty acids by titration after a 24hr incubation
Cherry crandall method
205
Amylase isoenzyme
S type-ptyalin
| P type-amylopsin
206
Catalyzes the same reaction made by ALP except that is active at pH5.0
Acid phosphatase ACP
207
Specific substrate of choice for quantitative endpoint reaction in ACP
Thymolphthalein monophosphate
208
Amylase in acute pancreatitis
Onset:2-12hrs
Peak:24hrs
Normalize:3-5days
209
Inhibitor of prostatic ACP
L-tartrate
210
Lipase EC code
EC3.1.1.3
211
Newborn screening marker
G6PD
212
Earliest pancreatic marker
Amylase
213
Coupling of several enzyme systems to monitor amylase activity
Continuous monitoring
214
G6PD EC code
EC1.1.1.49
215
Confirmed AMI occured
LD1>LD2
| CKMB >6%
216
ALP and GGT
Biliary tract obstruction
217
Useful serum markers for the diagnosis of AMI
Troponin I
218
Important in HMP
G6PD
219
ACP EC code
Ec3.1.3.2
220
Salivary amylase inhibitor
Wheat germ lectin
221
CKMB>6% and LD2>LD1
Myocardial damage, not necessarily AMI
222
Useful in the forensic clinical chemistry in the investigation of rape cases
ACP
223
Enzymes in bone disorders
ALP and ACP
224
Common chronic skeletal disease
Excessive resorption of bone by osteoclastic activity
Irregular pattern of bone deposition
Pagets disease
225
Increased osteoblastic activity
| Vitamin D deficiency
Rickets-children
| Osteomalacia-adult
226
Effect of PTH to calcium and phosphorus
| Little osteoblastic activity
Hyperparathyroidism
227
In acute pancreatitis lipase:
Onset:6hrs
Peak:24hrs
Remain elevated:7days
Normalize:8-14days
228
Most specific pancreatic marker
Lipase
229
For the diagnosis of prostatic carcinoma
ACP
230
LD2
Variety of noncardiac disorders
231
Identify angina patients with high risk of having AMI
Troponin T
232
AST increased
Liver cell necrosis
233
Common bone tumor
Osteogenic sarcoma
234
Ratio of acute pancreatitis
7-15%
235
Renal clearance decreased
| Low ratio of <2%
Macroamylasemia
