BIOCHEMISTRY W/1 TERM ACHEIVE ACCESS
9th Edition
ISBN: 9781319425746
Author: BERG
Publisher: MAC HIGHER
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Question
Chapter 28, Problem 15P
Interpretation Introduction
Interpretation:
The reason for the drop in IC50 value from 20 µMto 1 µM is not at all surprising shouldbe determined.
Concept introduction:
The IC50, half maximal inhibitory concentration, is the capacity of a substance to inhibit biological molecules and biochemical reactions. IC50 is the quantitative measurement of the inhibitor, which indicates the amount of inhibitor required to inhibit the biological substance.
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you are trying to come up with a drug to inhibit the activity of an enzyme thuogth to have a role in a liver disease. in the lab the enzyme was shown to have a Km of 1x10-6 M and Vmax of 0.1 micromoles/min.mg measruing at room temperature. you developed a mixed non-competitve inhibitor with a ki=0.4x10-6M and a Ki` pf 0/2 x 10-5 What will be the apparent Km in the presence of 1.0x10-6 M?
Please explain how it is that you approach a problem like this. For example, how would i be able to answer it if instead of met it said Lys, but also explain how you chose the enzyme for met. Thank you, i'll give a positive rate if the taks above is done.
The objective is to study a novel protease P isolated from the digestive tract of an
Amazonian insect. This protease can exist into two forms Pi and Pa which have
identical amino acid sequences (both of 80 kDa). However, only Pa shows proteolytic
activity. To better understand the activation mode of Pi (inactive form) in Pa (active
form), the following experiment was done using DIPF.
DIPF (diisopropylphosphofluoridate) is a well-known irreversible inhibitor of serine
proteases. It reacts with the catalytic serine residue of the active site of proteases as
shown below:
Enzyme -CH₂OH +
CH(CH3)2
O
F-P=0
O
CH(CH3)2
Diisopropylphospho-
fluoridate (DIPF)
Enzyme
-CH,—O
CH(CH3)2
O
<=0
O
CH(CH3)2
DIP-Enzyme
Both proteases Pa and P₁ were incubated with 32P-DIPF for 30 min at 37°C, and then
dialysed to remove excess of unreacted radiolabelled reagent. The two proteases
were then analyzed in Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis
(SDS-PAGE), with and without 2-mercaptoethanol.…
Chapter 28 Solutions
BIOCHEMISTRY W/1 TERM ACHEIVE ACCESS
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