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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**

**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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