First midterm content

Question 1

What is the formula for calculating side chains?

Answer 1

pH = pKa + log(dep/prot)
=10^pH-pKa
a/1-a=deprot
1-deprot=prot
then multiply it by the charge

Question 2

Which AA can act as a general base and acid?

Answer 2

His

Question 3

Name the negative AA

Answer 3

Asp and Glu

Question 4

Name the positive AA

Answer 4

Arg, His, Lys

Question 5

Which AA are prot at -1 and deprot at 0
Draw these

Answer 5

R (arg)
H (his)
K (lys)

Question 6

Which AA are prot at = and deprot at -1
Draw these

Answer 6

C (cys)
Y (tyr)
D (asp)
E (glu)

Question 7

Prot and deprot values of -N and -C

Answer 7

N deprot = 0 prot = +1
C deprot = -1 prot = 0

Question 8

What AA are polar uncharged?
Draw these

Answer 8

Ser
Thr
Asn
Gln

Question 9

What does TLC separate based on?

Answer 9

polarity = np elutes first

Question 10

What does GFC separate based on?

Answer 10

size = bigger first

Question 11

What does electro… separate based on?

Answer 11

size = smaller first

Question 12

What do 2D gels separate based on?
Name 2

Answer 12

weight = smallest first
isoelectric focusing and SDS electrophoresis

Question 13

kinetics formula

Answer 13

Vo/Vmax = [S]/Km+[S]

Question 14

If gives you 75% Vmax and asks you to find S?

Answer 14

0.75/1-0.75

Question 15

If gives you S=20 but asks you to find Vmax?

Answer 15

0.20/1+0.20

Question 16

Formula for thickness

Answer 16

= turns x 5.4

Question 17

Which AA are the breakers?

Answer 17

GPNDS

Question 18

Which AA like B?

Answer 18

WYFVITC

Question 19

Mechanisms of chymotrypsin:
____ negative charge makes _____ positive. His is now a _____ which takes _____ H making Ser a better ______ to attack C=O.

Answer 19

Asp, His
base, Ser, nucleophile

Question 20

Specific activity formula

Answer 20

SA = Ea/ttl protein

Question 21

When an enzyme is purified SA = ____, Total protein = ____ and EA = ____

Answer 21

increases, decreases, decreases