11- protein targets-enzyme

Question 1

list the four different protein targets for drugs

Answer 1

• enzymes
• receptors
• ion channels
• structural proteins (uncommon)

Question 2

explain the enzymes as protein targets

Answer 2

• Drug usually stops the enzyme from working
• Drug exerts effect by preventing the production of the enzyme product
• can’t switch an enzyme on, or make it better- just prevent enzyme from working
• indirect effect
• lack of them produces effect that you want from your drug

Question 3

explain the receptors as protein targets

Answer 3

• carry information inside of cell to out, or other way around- across a membrane
• Drug can activate (agonist) or deactivate (antagonist) the receptor
  
  • amplify or suppress
• Some drugs perform both functions
• Drug exerts effects by amplifying or suppressing receptor function

Question 4

explain the ion channels as protein targets

Answer 4

• Drug can open or close the channel
• Some drugs perform both functions
• Drug exerts effects by amplifying or suppressing channel function
• sometimes called modulators and affect how ion channels work (open or close it)

Question 5

explain the structural proteins as protein targets

Answer 5

• Drugs interfere with the assembly or disassembly of certain protein structures
• quaternary structure or disassembly of a quaternary structure

Question 6

what are the percentages of each of the targets in top 50 drugs

Answer 6

• Enzyme inhibitor 38 %
• Receptor antagonist 24 %
• Receptor agonist 12 %
• Ion channel modulator 8 %
• Unknown or Misc. 18 %

Question 7

what is the reaction for the designer solvent?

Answer 7

enzyme (substrate ->) E-S complex (very close contacts and tight binding ->) E-P complex (product ->) E

Question 8

enzyme active sites are ____

Answer 8

relatively small

Question 9

explain the two purposes that the AA chains serve in terms of the enzyme-substrate reaction

Answer 9

• only a few AA actively participate in the reactions
• all of other AA chains are just there to make sure the chains are held in the right shape to interact with the substrate and produce the reaction the enzyme will catalyze

Question 10

describe the two complimentary things that are present in the active site-transition state thing

Answer 10

• a pocket in enzyme that the substrate is designed to go inside
• non bonded interactions have complementarity: charges, van der wall surfaces

Question 11

describe the process of enzyme binding to substrate (ES complex)

Answer 11

• Forms the enzyme-substrate complex (ES)
• Equilibrium- substrate always coming off and on
• Enzyme normally changes shape to accommodate substrate
• Substrate also changes shape

Question 12

describe the process of the reaction occurring- the S turning into P

Answer 12

• The components in the ES complex (ES) now is correct alignment to facilitate reaction
• Substrate is converted into the product in the active site
• Enzyme may change shape during this process in other cases not visible

Question 13

explain the process of the P being released

Answer 13

• also equilibrium
• The components in the ES complex (ES) now is correct alignment to facilitate reaction
• Substrate is converted into the product in the active site
• Enzyme may change shape during this process
• enzyme changed back

Question 14

two theories of enzymatic conformational change

Answer 14

• Lock and key (older)
  
  • Enzyme binding pocket is the exact shape for the substrate
  • it assumes that neither molecule changes shape
• Induced fit
  
  • Binding of substrate or other molecule changes conformation of the enzyme
  • both cause each other to change until they bind
  • Conformational change “activates” or “deactivates” the enzyme
  • Remember that the substrate is also flexible and will change conformation during binding

Question 15

are molecules static?

Answer 15

NO period