PRELIM LESSON#1: INTRODUCTION TO ENZYMATICS Flashcards
Study of enzymes: activity of enzymes, chemical reaction they create, clinical uses
ENZYMOLOGY
○ present inside tissues and cells
○ Not common in the circulation
ENZYMES
_________ act as Biological catalysts
ENZYMES
Hasten chemical reactions
ENZYMES
___________are not consumed during the reactions
ENZYMES
__________ is not diagnostic to a certain
disease, but it is useful in specifying which organ is
affected
Enzyme testing
Enzyme + Substrate = __________
Product
_____________are categorized according to what they catalyze
Enzymes
recognizes and catalyzes a single substrate
ABSOLUTE
Recognizes and catalyzes a group of
substrates that have specific functional
groups
GROUP
Recognizes and catalyzes a group of
substrates that have a particular type of
bond
LINKAGE
Enzyme specificity has three groups
Absolute
Group
Linkage
3 NOMENCLATURE OF ENZYMES
SRE
1) Substrate + -ase
2) Reaction it catalyzes
3) Enzyme Commission Nomenclature (E.C.)
Lipid = __________
lipase
Ester = __________
esterase
Protein = ________
protease
Amylose = ___________
amylase
Lactose = ___________
lactase
Oxidation = __________
oxidase
Reduction = ___________
reductase
Hydrolysis = ___________
hydrolase
_________ = remove hydrogen atoms
Dehydrogenase
_________ = remove carboxyl groups
Decarboxylase
ex. E.C. 1.1.1.21
3) Enzyme Commission Nomenclature (E.C.)
1st digit =_______
○ Based on the OTHLIL classification
● 2nd digit = _______
● 3rd and 4th =_________
class
subclass
serial number
The names of some enzymes do not end in -ase
ex. _______, _________
pepsin, trypsin
__________ - active form of pepsinogen
Pepsin
_____________- active form of trypsinogen
Trypsin
2) Reaction it catalyzes
(5 examples)
ORHDD
Oxidation
reduction
hydrolysis
dehydrogenase
decarboxylase
1) Substrate + -ase
(5 examples)
Lipids
Esterase
Protein
Amylose
Lactose
OTHLIL CLASSIFICATION OF ENZYMES
OTHLIL
● Oxidoreductases
● Transferases
● Hydrolases
● Lyases
● Isomerases
● Ligases
removal of H ion / electrons
Oxidation
acceptance of H ion / electrons
Reduction
Ex. E.C. 1.1.1.27: L-lactate NAD+ Oxidoreductase
○ Lactate dehydrogenase
OXIDOREDUCTASES
Transfer of functional groups other than hydrogen from one substrate to another
2) TRANSFERASES
Ex. E.C. 2.6.1.1 : L-Aspartate: 2-Oxaloglutarate
Aminotransferase
○ Aspartate Aminotransferase
TRANSFERASES
Hydrolysis of various bonds
HYDROLASES
○ Addition of water to a bond resulting in bond breakage
3) HYDROLASES
Ex. E.C. 3.1.1.3 : triacylglycerol lipase
3) HYDROLASES
Catalyze the removal of groups from substrates without hydrolysis or oxidation
4) LYASES
the product contains double bonds or a ring
4) LYASES
Rearrange the functional groups within a molecule and catalyze the conversion of one isomer into another
Ex. Phosphoglycerate mutase
ISOMERASES
Catalyze the joining of two large molecules by forming a new chemical bond
Ex. DNA ligase
6) LIGASES
● Site where enzyme binds to the substrate
ACTIVE SITE
● Has the same shape as substrate
● Two types: lock and key, induced fit
ACTIVE SITE
Binding site on enzyme where activators and inhibitors bind
ALLOSTERIC SITE
Changes the structure of the active site to prevent substrate binding
Inhibitor
Changes the shape of the active site to the appearance of the substrate to promote binding
Activator
● Acted upon by the enzyme
● Specific
SUBSTRATE
Different form but with the same action
ISOENZYME
● Non-protein molecule
● Facilitate enzymatic reactions
● Not all reactions require cofactors
COFACTOR
Some enzymes require cofactors
● Without cofactors: ____________
● With cofactors: _____________
Some enzymes require cofactors
● Without cofactors: inactive apoenzyme
● With cofactors: active holoenzyme
● tightly bound
● Metal ions (activators) or organic molecules
● Change the configuration of the enzyme/link
substrate to enzyme/coenzyme
PROSTHETIC GROUPS
● loosely bound
● Organic molecules
● “second substrate” for enzyme reactions
COENZYMES
what are the two TYPES OF COFACTORS
PROSTHETIC GROUPS and COENZYMES
● Polypeptide portion
● Inactive enzyme
APOENZYME
Apoenzyme + Coenzyme
HOLOENZYME
● Also known as zymogen
● Enzyme precursor; inactive
● No active site
● Converted by proteolysis
Ex: Trypsinogen to Trypsin
________________________
PROENZYME
Chymotrypsinogen to Chymotrypsin
