Monday , 21 April 2014

Assam TET Answer key 2014 Assam TET Paper Solution

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Assam TET Answer key 2014, Assam TET Paper Solution 2014, Assam TET Solved Answer sheet 2014, Assam TET 2014 Answer Key, Assam TET Answer key Download

Most people have two forms of the acetaldehyde dehydrogenase, a low K M mitochondrial form and a high K M cytosolic
form. In susceptible persons, the mitochondrial enzyme is less active due to the substitution of a single amino acid, and
acetaldehyde is processed only by the cytosolic enzyme. Because this enzyme has a high K M, less acetaldehyde is
converted into acetate; excess acetaldehyde escapes into the blood and accounts for the physiological effects.
8.4.1. The Significance of K M and V max Values
Conceptual Insights, Steady-State Enzyme Kinetics. Learn how the kinetic
parameters KMand Vmaxcan be determined experimentally using the enzyme
kinetics lab simulation in this media module.

Assam TET Answer key 2014 Assam TET Paper Solution

The Michaelis constant, K M, and the maximal rate, V max, can be readily derived from rates of catalysis measured at a
variety of substrate concentrations if an enzyme operates according to the simple scheme given in equation 23. The
derivation of K M and V max is most commonly achieved with the use of curve-fitting programs on a computer (see the
appendix to this chapter for alternative means of determining K M and V max). The K M values of enzymes range widely
(Table 8.5). For most enzymes, K M lies between 10-1 and 10-7 M. The K M value for an enzyme depends on the
particular substrate and on environmental conditions such as pH, temperature, and ionic strength. The Michaelis
constant, K M, has two meanings. First, K M is the concentration of substrate at which half the active sites are filled.
Thus, K M provides a measure of the substrate concentration required for significant catalysis to occur. In fact, for many
enzymes, experimental evidence suggests that K M provides an approximation of substrate concentration in vivo. When
the K M is known, the fraction of sites filled, f ES, at any substrate concentration can be calculated from
Second, K M is related to the rate constants of the individual steps in the catalytic scheme given in equation 9. In
equation 15, K M is defined as (k -1 + k 2)/k 1. Consider a limiting case in which k -1 is much greater than k 2. Under such
circumstances, the ES complex dissociates to E and S much more rapidly than product is formed. Under these conditions
(k -1 >> k 2),
The dissociation constant of the ES complex is given by
In other words, K
M
is equal to the dissociation constant of the ES complex if k
2
is much smaller than k- 1
. When this
condition is met, K M is a measure of the strength of the ES complex: a high K M indicates weak binding; a low K M

 


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