Question

An enzyme catalyzes the reaction A --> B. The enzyme is present at a concentration of...

An enzyme catalyzes the reaction A --> B. The enzyme is present at a concentration of 2 nM, and the Vmax is 1.2 mm/s. The Km for substrate A is 10 mM. Calculate the initial velocity of the reaction, Vo, when the substrate concentration is a) 4 mM, b) 15 mM, c) 45 mM.

Homework Answers

Answer #1

Et= concentration of enzyme= 2nM =2*10-9 M   , Vmax= 1.2 mM/s= 1.2*10-3 M/s, KM= 10mM= 10*10-3 M

From Michaelis-Menten Kinetics, V= initial velocity = VmaxS/(KM +S)

a) for S= 4mM= 4*10-3M, V= 1.2*10-3* 4*10-3/( 10*10-3 +4*10-3)= 4.8*10-6/ 14*10-3= 0.0003429 M/s

b) for S= 15mM= 15*10-3M, V= 1.2*10-315*10-3/ (10*10-3 +15*10-3)= 1.2*15/*10-3/25= 7.2*10-4 M/s

c) for S= 45mM =45*10-3M, V= 1.2*10-3*45*10-3/ (10*10-3+45*10-3)= 1.2*45*10-3/58= 9.3*10-4 M/s

From

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
The following parameter(s) of an enzyme-catalyzed reaction depend(s) on enzyme concentration: A) Km (Michaelis constant) B)...
The following parameter(s) of an enzyme-catalyzed reaction depend(s) on enzyme concentration: A) Km (Michaelis constant) B) Vmax (maximum velocity) C) kcat (turnover number) D) A and B E) B and C Km is the equivalent of: A) Substrate concentration at Vo B) Substrate concentration when Vmax is reached C) Substrate concentration when 1/2 Vmax is reached D) Product concentration when 1/2 Vmax is reached
An enzyme catalyzes a reaction with an initial velocity of 50 micromoles/litre-seconds when the substrate concentration...
An enzyme catalyzes a reaction with an initial velocity of 50 micromoles/litre-seconds when the substrate concentration is 5 micromolar and 80 micromoles/litre-seconds when the substrate concentration is 10 micromolar. The Vmax and Km of this enzyme are: A) 50 micromoles/litre-seconds; 5 micromolar B) 80 micromoles/litre-seconds; 10 micromolar. C) 200 micromoles/litre-seconds; 15 micromolar D) 100 micromoles/litre-seconds; 12.5 micromolar E) 10 micromoles/litre-seconds; 1 micromolar
An enzyme is discovered that converts substrate A to product B. The molecular weight of the...
An enzyme is discovered that converts substrate A to product B. The molecular weight of the enzyme is 10000 Daltons. The Km and Vmax values for the enzyme are shown below: Km (mM) 2 Vmax (mmole/min/mg) 20 What is the reaction initial velocity for this enzyme when the concentration of A is 4 mM? What is the turnover number of this enzyme?
For an enzyme-catalyzed reaction, the initial velocity was determined at two different concentrations of the substrate....
For an enzyme-catalyzed reaction, the initial velocity was determined at two different concentrations of the substrate. Which of the following would be closest to the value of Vmax? For an enzyme-catalyzed reaction, the initial velocity was determined at two different concentrations of the substrate. Which of the following would be closest to the value of Km? [S] (mM) Vo(mM/min) 1.0 2.0 4.0 2.8
20. You run a reaction with 1 µg of enzyme QB26, buffer and 25 millimolar (mM)...
20. You run a reaction with 1 µg of enzyme QB26, buffer and 25 millimolar (mM) substrate and obtain an initial reaction velocity (vo) of 100micromolar (µM) product per second. You repeat the reaction the same as before but with 50 mM substrate and observe vo = 101µM/sec, repeat at 100mM substrate, get vo =102µM/sec. a. The substrate concentrations in these reactions are very close the Km b. The velocities in these reactions are very close to Vmax c. The...
Questions about biochem: 1.) If the ΔG'° of the reaction A --> B is +1000 kJ/mol,...
Questions about biochem: 1.) If the ΔG'° of the reaction A --> B is +1000 kJ/mol, under standard conditions the reaction will never reach equilibrium. True or False ? 2.) An enzyme catalyzes the reaction A↔B. The enzyme is present at a concentration of 4 nm, and the Vmax is 1.5 µM s-1. The Km for substrate A is 10 µM. Which of the following is the initial velocity of the reaction Vo when the substrate concentration is 10 µM?...
An enzyme is found that catalyzes the reaction A ↔B. In an experiment with total enzyme...
An enzyme is found that catalyzes the reaction A ↔B. In an experiment with total enzyme concentration of 5 nM, Vmax is 1.5 μM s^-1. What is kcat for the enzyme. Give your answer as a number only in units of s^-1.
1) For an enzyme that displays Michaelis-Menten kinetics, what is the initial velocity as a function...
1) For an enzyme that displays Michaelis-Menten kinetics, what is the initial velocity as a function of Vmax when: i) [S] = Km ii) [S] = 0.1 Km iii) [S] = 50Km 2) An enzyme (follows Michaelis-Mentin Kinetics) has Km = 0.5 M. The initial velocity is 0.2 Mmin-1 at substrate concentration of 50 M. What is the Vmax? What is the initial velocity when a) [S] = 2 M and b) [S] = 0.5 M? 3) What will be...
For any enzyme that follows simple Michaelis-Menten kinetics, when the initial velocity of the reaction is...
For any enzyme that follows simple Michaelis-Menten kinetics, when the initial velocity of the reaction is 1/5 of Vmax what is the Substrate concentration? A) KM << [S] B) KM = 1/5[S] C) KM = 4[S] D) KM = 5[S] E) KM = [S]
An enzyme catalyzes the reaction A -> B +H2O. If km for this reaction is 100uM...
An enzyme catalyzes the reaction A -> B +H2O. If km for this reaction is 100uM and vmax is 4umol/min/mg enzyme, calculate the amount of B formed in 2.0 min by 1.0 mg enzyme with 50uM A in solution.