What is Km significance?

What is Km significance? 
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Answer :

Km is independent of enzyme concentration. Km value is thus constant for an enzyme. It is the characteristic feature of a particular enzyme for a specific substrate. Km denotes the affinity of enzyme to substrate. Thus, the lesser the numerical value of Km, the affinity of the enzyme for the substrate is more.
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In competitive enzyme activity inhibition (A) The structure of inhibitor generally resembles that of the substrate (B) Inhibitor decreases apparent Km (C) Km remains unaffective (E) Inhibitor decreases Vmax without affecting Km

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In reversible non-competitive enzyme activity inhibition (A) Inhibitor bears structural resemblance to substrate (B) Inhibitor lowers the maximum velocity attainable with a given amount of enzyme (C) Km is increased (D) Km is decreased

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In reversible non-competitive enzyme activity inhibition (A) Vmax is increased (B) Km is increased (C) Km is decreased (D) Concentration of active enzyme is reduced

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The kinetic effect of purely competitive inhibitor of an enzyme (A) Increases Km without affecting Vmax (B) Decreases Km without affecting Vmax (C) Increases Vmax without affecting Km (D) Decreases Vmax without affecting Km

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The Km of the enzyme giving the kinetic data as below is (A) –0.50 (B) –0.25 (C) +0.25 (D) +0.33

Description : The Km of the enzyme giving the kinetic data as below is (A) –0.50 (B) –0.25 (C) +0.25 (D) +0.33

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From the L ineweaver-Burk p lot of Michaelis-Menten equation, Km and Vmax can be determined when V is the reaction velocity at substrate concentration S, the X-axis experimental data are expressed as (A) 1/V (B) V (C) 1/S (D) S

Description : From the L ineweaver-Burk p lot of Michaelis-Menten equation, Km and Vmax can be determined when V is the reaction velocity at substrate concentration S, the X-axis experimental data are expressed as (A) 1/V (B) V (C) 1/S (D) S

Last Answer : Answer : C

Glucokinase (A) Is widely distributed and occurs in most mammalian tissues (B) Has a high km for glucose and hence is important in the phosphorylation of glucose primarily after ingestion of a carbohydrate rich meal (C) Is widely distributed in Prokaryotes (D) None of these

Description : Glucokinase (A) Is widely distributed and occurs in most mammalian tissues (B) Has a high km for glucose and hence is important in the phosphorylation of glucose primarily after ingestion of a carbohydrate rich meal (C) Is widely distributed in Prokaryotes (D) None of these

Last Answer : B

What is the use of assessing the Km value of an enzyme? What is the application?

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Last Answer : Determination of Km value is also useful to understand the natural substrate of an enzyme. Study of Km value will also differentiate the competitive and non-competitive inhibitions.

What is Km value?

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Last Answer : Substrate concentration (expressed in moles/L) at half-maximal velocity is the Km value.