EXAM1_L10_Enzymes

Question 1

6 types of enzymes

Answer 1

1. oxidoreductases
2. Transferases (CNP groups)
3. Hydrolases (cleavage by adding water)
4. Lyases (cleavage of C-C,C-S,C-N)
5. Isomerases (racemization of optical/geo isomers)
6. Ligases (bind C and O,S,N; coupled to hydrolysis)

Question 2

What kind of bonds need to be broken to be considered a Lyase? or Ligase? transferase?

Answer 2

CC, CN, CS
Ligase C to OSN
Transferase CNP groups

Question 3

Cofactor,Metal ion, organic cofactor, cosubstrate, prosthetic group

Answer 3

Cofactor- mol req for enzyme activity
metal- Fe3+,Zn2+,Cu2+
organic cofactor- coenzyme
cosubstrate- coenzyme used in transit
prosthetic group- permanent coenzyme (heme in hb)

Question 4

who is founder of Lock & Key model? when?

Induced fit model? when?

Answer 4

Fischer 1890

Koshland, 1958 (68 years later)

Question 5

Enzymes stereospecific and functional group specific- They might ask a question and have D or L sugar or alpha beta. make sure you pay attention to DETAILS Slow down think about every part

Answer 5

lactate dehydrogenase- L stereospecific

Question 6

Binding energy from where? Weak interactions of ES provide what? Enzyme shaped more like the transition state than the substrate

Answer 6

binding energy created by formation of multiple weak covalent bonds of ES.
Weak interactions of ES provide strong force for catalysis

Question 7

glycopeptidyl transferase (GT) essential bacterial protein to make cell wall.  GT catalyzes xlink substrate is\_\_\_\_\_ dipeptide.
\_\_\_\_\_\_ is a transition state analog that \_\_\_\_ \_\_\_\_ to GT and inactivates the enzyme

Answer 7

alanine-alanine dipeptide.

Penicillin binds covalently to GT- inactivating the enzyme