Enzyme Mechanism of Action Flashcards
Changes in the ____ and ____ of enzymes can be determined by blood tests.
Quantity and activity
Genetic defects, _____ deficits, ____ damage, the presence of toxins, the activity of bacterial/viral agents, and enzyme _____/____ all can lead to changes in enzyme activity and yield pathological conditions.
genetic defects, nutritional deficits, tissue damage, the presence of toxins, the activity of bacterial/viral agents, and enzyme inhibitors or activators
What are four reasons enzymes are the preferred catalysts?
Work at milder conditions, can be regulated, reaction specificity, increase reaction rates
What are RNA enzymes called?
RNases or ribozymes
This enzyme types transfers electrons.
oxidoredcutase
This enzyme type transfers groups
transferase
This enzyme type removes a functional group with water.
hydrolase
This enzyme types cleaves bonds via elimination (pi bond) or adds a group to a pi bond.
lyase
This enzyme type transfers groups within a molecule to yield isomers.
isomerase
This enzyme type forms C-C, C-O, C-N, C-S bonds via condensation and ATP.
ligase
“Forms CONS bonds via CONdenSation and ATP”
What are nonprotein enzyme aids called?
Coenzymes, cofactors, prosthetic groups
Prosthetic groups are different from cofactors because they are _____ of the enzyme.
part
What are two examples of cofactors in TCA?
NAD+, FAD
Many coenzymes are derivatives of…
vitamins
Enzymes without the necessary cofactors are called____. What is the opposite?
apoenzymes, holoenzymes
NAD+ is _____ while FAD is bound.
mobile
Can be derived from Trp in humans and vitamin B3
niacin
Describe the four types of enzyme catalysis.
Covalent: formation of a covalent intermediate with the substrate before the product is formed
Acid Base: group on enzyme acts as an acid or base, taking away or giving a H+ to the substrate.
Proximity: if substrate is available at high concentration and is close enough to the enzyme, a reaction will occur
Strain: enzyme binds the substrate in a statically unfavorable way to break the necessary bond
What is the benefit of having 60 active site on PDH?
High level of processing and keeps metabolites at high concentration
What are examples of the induced fit model and the lock and key model?
Induced fit: hexokinase and citrate synthase
Lock and key: dihydrofolate reductase
What are the differences between enzymes and isoenzymes?
Isoenzymes can have different reaction rates and inhibition rates.
What is the benefit of have isoenzymes?
backup in the body because have same function as general enzyme
Elevated levels of isoenzymes could indicate _____.
disease
Lactate DH has two main isoenzymes. What are they? What are their function? Where are they found?
LDH 5 is found in the muscles. Takes pyruvate to lactate.
LDH 1 is found in the heart. Takes lactate to pyruvate.
Serine proteases often interact in _____ catalysis. Aspartate proteases (like in HIV) often interact in _____ catalysis.
Covalent, acid
If thiamin pyrophosphate (TPP) is missing, what illness results?
Beriberi
Derived from vitamin B1
Serum amylase suggests what illness?
Acute pancreatitis
What enzymes compose the PDH complex?
E1: Pyruvate Dehydrogenase
E2: Dihydrolipoyl transacetylase
E3: Dihydrolipoyl dehydrogenase
What are the prosthetic groups/coenzymes of PDH?
TPP -bound to E1. Aldehyde transfer Lipoate - covalently linked to E2. Aceyl group transfer Coenzyme A - substrate for E2 FAD - bound to E3 NAD - substrate for E3-reduced by FADH2
What does a dietary deficiency in niacin cause?
pellagra
Tetrahydrofolate (THF) deficiency can result in?
spinabifida
The majority of enzyme/protein based diseases are cause by—-
mutations in evolutionarily conserved residues
NAD+(P)- dependent DH produce a fluorescent product. What how does this help with enzyme activity quantification?
340 nm is where NADPH absorbs. See how much NADPH there is to determine the enzyme activity.
Both (NAD (P) and NAD(P)H) absorb at 250 so don’t want to look at that portion of the absorbency spectrum
What is tetrahydrofolate’s (THF) role in reaction?
Transfers one carbon units on its N5
