MIDTERM 01 - Enzymes & Isolation and Characterization of Nucleic Acids Flashcards
Are proteins that acts as catalysts in biochemical reactions
Enzymes
A substance that can be added to a reaction to increase the reaction rate without getting consumed in the process
Catalysts
A disaccharide composed of an alpha-D-glucose molecule + beta D-fructose molecule linked by alpha-1,4-glycosidic bond
Sucrose/Table sugar
A liquid sweetener made from table sugar (sucrose) and water
Invert sugar
A beta-fructofuranosidase mainly used in the food (confectionery) industry
Invertase
Commercial invertase is biosynthesized by yeast strains of __________ or __________
Saccharomyces cerevisiae, Saccharomyces calsbergensis
Are sugars capable of acting reducing agents because it has a free aldehyde group or a ketone group
Reducing sugars
1 example of non-reducing sugar
Sucrose
Glucose + Glucose = __________
Maltose
Glucose + Galactose = __________
Lactose
Glucose + Fructose = __________
Sucrose
An aromatic compound that reacts with reducing sugars and other reducing molecules to form 3-amino-5-nitrosalicylic acid
DNS/3,5-dinitrosalicylic acid
DNS strongly absorbs light at __________ nm
540 nm
Method that detects the presence of free carbonyl group of reducing sugars; it involves the oxidation of aldehydes in glucose and ketones in fructose
DNS colorimetric method
The most favorable pH value; the point where the enzymes are most active
Optimum pH
Most of the enzymes rapidly become denatured at temperature above __________°C
40°C
Storage of enzymes at __________°C or below is generally the most suitable
5°C
Enzyme that contains only substrate and enzyme
Simple enzyme
Enzymes that are made up of protein groups (Apoenzyme) and nonprotein component (Cofactor)
Holoenzyme
Other name for Vitamin B2
Riboflavin
Other name for Vitamin B3
Niacin
Other name for Vitamin B5
Pantothenic acid
Meaning of FADH2
Flavine Adenine Dinucleotide
A cofactor that is bound tightly to the apoenzyme and is difficult to remove without damaging the enzyme
Prosthetic groups
Catalyze redox reactions (Enzyme classifications)
Oxidoreductase (EC 1)
Catalyzes the transport of 1 functional group from 1 molecule to another (Enzyme classifications)
Transferase (EC 2)
Catalyzes hydrolytic reaction or the breaking of bond involving the introduction of water (Enzyme classifications)
Hydrolase (EC 3)
Catalyzes non-hydrolytic cleavage-removal of a double bond or the breaking of a bond by an interaction of functional group (Enzyme classifications)
Lyase (EC 4)
Catalyzes the intramolecular rearrangement of atoms (Enzyme classifications)
Isomerase (EC 5)
Catalyzes reaction that join 2 molecules forming covalent linkage using an energy released from hydrolyzing pyrophosphate bond (Enzyme classifications)
Ligase (EC 6)
An enzyme catalyzing the hydrolysis of fats; secreted by the pancreas and liver (Enzymes used in clinical diagnosis)
Lipase
Plasma lipase level may be __________ in liver disease, vitamin A deficiency, some malignancies, and diabetes
Low
An enzyme concerned with the breakdown of dietary starch and glycogen to maltose; present in pancreatic juices and saliva (Enzymes used in clinical diagnosis)
α-Amylase
Plasma amylase level may be __________ in liver disease
Low
Plasma amylase level may __________ in intestinal obstruction, mumps, acute pancreatitis, and diabetes
Increase
Secreted by the pancreas; elevated levels of this in plasma may occur during acute pancreatic disease (Enzymes used in clinical diagnosis)
Trypsin
Are a group of enzymes which hydrolyze phosphate esters at an alkaline pH; found in bone, liver, kidney, intestinal wall, lactating mammary gland, and placenta (Enzymes used in clinical diagnosis)
Alkaline phosphatases (ALP)
Alkaline phosphatase (ALP) levels may be __________ in rickets and osteomalacia, hyperparathyroidism, Paget’s disease of bone, obstructive jaundice, and metabolic carcinoma (Enzymes used in clinical diagnosis)
Increased
Serum alkaline phosphatase (ALP) levels may __________ in CHF as a result of injury to the liver
Increase
Catalyzes hydrolysis of various phosphate esters at acidic pH; found in the prostate, liver, red blood cells, platelets, and bone (Enzymes used in clinical diagnosis)
Acid phosphatase (ACP)
Acid phosphatase (ACP) levels may __________ in metastatic prostatic carcinoma
Increase
Catalyzes the transfer of the amino group of aspartic acid to α-ketoglutarate forming glutamate and oxaloacetate; widely distributed and has a high concentration in the heart, liver, skeletal muscle, kidney, and erythrocytes (Enzymes used in clinical diagnosis)
Aspartate transaminases (AST) or Glutamate oxaloacetate transaminase (GOT)
Catalyzes the transfer of the amino group of alanine to α-ketoglutarate, forming glutamate and pyruvate; present in high concentration in the liver and to a lesser extent in skeletal muscle, kidney, and heart (Enzymes used in clinical diagnosis)
Alanine transaminase (ALT) or Glutamate pyruvate transaminase (GPT)
Serum levels of __________ and __________ are useful in the diagnosis of liver parenchymal damage and myocardial damage respectively
Serum glutamate pyruvate transaminase (SGPT) and Serum glutamate oxaloacetate transaminase (SGOT)
In liver damage, both SGPT and SGOT increase, but __________ increases more
SGPT
In myocardial infarction, __________ is increased with little or no increase in SGPT
SGOT
2 theories of enzyme binding
Lock and key, Induced fit
In the same way only certain keys fit a lock, only certain substrates fit an enzyme’s active site (Theories of enzyme binding)
Lock and key
The shape of the active site within enzymes is malleable and can be induced to fit the substrate through a variety of mechanisms (Theories of enzyme binding)
Induced fit
Binding of __________ leads to activity
Agonist
Binding of __________ leads to loss of activity
Antagonist
__________ refers to the maximum rate of the reaction
Vmax
__________ refers to the concentration of substrate which permits the enzyme to achieve half Vmax
Km (Michaelis constant)
__________ inhibition results to same Vmax, but increased Km
Competitive inhibition
__________ inhibition results to decreased Vmax and same Km
Noncompetitive inhibition
__________ inhibition results to decreased Vmax and decreased Km
Uncompetitive inhibition
__________ inhibition is surmountable (by 1 concentration)
Competitive inhibition
__________ inhibition is insurmountable or irreversible
Noncompetitive inhibition
__________ inhibition is similar to noncompetitive inhibition that are insurmountable or irreversible, except it only affects the enzyme-substrate complex
Uncompetitive inhibition
Catalyzes the reversible interconversion of lactate and pyruvate; widely distributed with high concentration in the ear, skeletal muscle, liver, kidney, brain, and erythrocytes (Enzymes used in clinical diagnosis)
Lactate dehydrogenase (LDH)
Lactate dehydrogenase (LDH) is __________ in plasma in MI, acute leukemia, generalized carcinomatosis, and acute hepatitis
Increased
Found in the heart muscle, brain, and skeletal muscle; measurement of this is of value in the diagnosis of disorders affecting the skeletal and cardiac muscle (Enzymes used in clinical diagnosis)
Creatine kinase/Creatine phosphokinase (CPK)
Also known as deoxyribonucleic acid; supplies the genetic information
DNA
These are informational molecules made up of polymers of nucleotides linked together by phosphodiester bonds
Nucleic acids
These are the building blocks of nucleic acids, composed of nitrogen-containing heterocyclic base, phosphate, and pentose sugar
Nucleotides
Are nucleotides that do not possess phosphate group; it only has heterocyclic base and pentose sugar
Nucleoside
2 types of nucleic acids in cells
DNA, RNA
Sugar present in DNA
2-deoxyribose
Sugar present in RNA
Ribose
Strand present in DNA
Double-stranded
Strand present in RNA
Single stranded
2 purine bases found in DNA and RNA
Guanine, Adenine
2 pyrimidine bases found in DNA
Cytosine, Thymine
2 pyrimidine bases found in RNA
Cytosine, Uracil
DNA to DNA (Information transmission)
Replication
DNA to RNA (Information transmission)
Transcription
RNA to proteins (Information tarnsmission)
Translation
A cationic detergent that facilitates the separation of polysaccharides during purification and aid in removing polyphenols; widely used when purifying DNA from plant tissues
CTAB
Full name of CTAB
Cetyl-trimethylammonium bromide
__________ mL: __________ g of the CTAB (Preparation of CTAB buffer)
100 mL, 2 g
__________ mL of the __________ M Tris-HCl (Preparation of CTAB buffer)
10 mL, 1 M
pH __________: __________ mL of the __________ M EDTA (Preparation of CTAB buffer)
pH 8: 4 mL, 0.5 M
__________ mL of the __________ M NaCl (Preparation of CTAB buffer)
26 mL, 5 M
__________ mL of the distilled water (Preparation of CTAB buffer)
58 mL
This is used in DNA isolation because it has a low starch content, which allows the DNA to be seen clearly
Onion
This is used because DNA is not insoluble in it, and when it is added to the mixture, all components of the mixture will stay in the solution and the DNA will precipitate
Ice cold ethanol
Test used to detect the presence of deoxyribose
Diphenylamine/Dische test
Test used to detect the presence of ribose
Bial’s orcinol test
The reaction between the Dische reagent and 2-deoxyribose results to the development of a __________
Blue color
Test used to detect the presence of phosphate ions
Test for phosphates
Test for phosphates involve the hydrolysis of pyrophosphates to phosphate, which leads to the formation of a __________
Bright yellow precipitate
Test used to detect the presence of ammonium purpurate or ammonium salts of purpuric acids
Murexide test
When Murexide test is used to test for the presence of uric acids, it results to a __________
Yellow residue
When Murexide test is used to test for the presence of xanthine, it results to a __________
Red residue
Test used to detect the presence of the pyrimidine bases, cytosine and uracil
Wheeler-Johnson test
When the Wheeler-Johnson test is treated with bromine water, it results to a __________
Green coloration
When the Wheeler-Johnson test is added with barium hydroxide, it results to a ___________
Purple liquid
In higher salt concentrations, __________ are insoluble
Polysaccharides
In lower salt concentrations, _________ is insoluble
DNA