2. Enzyme-catalyzed reactions. Answer the following with true or false. If false, explain why.(a) The initial rate of an enzyme-catalyzed reaction is independent of substrate concentration.(b) At saturating levels of substrate, the rate of an enzyme-catalyzed reaction is proportional to the enzymeconcentration.(c) The Michaelis constant Km equals the substrate concentration at which velocity (v) = Vmax/2.(d) The Km for a regulatory enzyme varies with enzyme concentration.(e) If enough substrate is added, the normal Vmax of an enzyme-catalyzed reaction can be attained even inthe presence of a noncompetitive inhibitor.(f) The Km of some enzymes may be altered by the presence of metabolites structurally unrelated to thesubstrate.(g) The rate of an enzyme-catalyzed reaction in the presence of a rate-limiting concentration of substratedecreases with time.(h) The sigmoidal shape of the v versus [S] curve for some regulatory enzymes indicates that affinity of theenzyme for the substrate decreases as the substrate concentration is increased.

Enzyme is a biological catalyst, protein in nature which can increase the chemical reaction without…

Answered: 2. Enzyme-catalyzed reactions. Answer…

Biochemistry

9th Edition

ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

. The optimal conditions for salivary lysozyme (hydrolyzing glycoproteins of bacterial wall) are 37 C - temperature and pH is 5.2. Explain the decrease in this enzyme activity if the temperature will rise up to 60 °C and pH will be changed to 8.0. To answer the question: a) draw the graph of the velocity dependency on temperature and pH; b) calculate the relative enzyme activity if 10 mg of lysozyme catalyzes the formation of 5 uM of the product per 2 minutes. Concidor NH3: 5.
calculate the reaction velocity at saturating substrate concentrations. Your numerical answer is assumed to be in units of M sec-1. [S] = 100 mM k1 = 10 sec-1 k2 = 3000 sec-1 k-1 = 20 sec-1 [E]T = 1 \muμM
1. For enzyme catalyzed reaction: ki S + E=X (fast) k2 X -2> P + E (slow) derive the rate law and answer the following: a) What is meant by Michaelis-Menten constant km? (b) Prove that order of reaction in substrate changes from unity to zero at higher [S]. (c) What is the rate and value of km, if k2 >> k1. (d) Draw the potential energy diagram for enzyme catalyzed reaction.
Select true if the statement is CORRECT and false if OTHERWISE 1. Enzymes are catalysts and increase the speed of a chemical reaction without themselves undergoing any permanent chemical change. 2. Catalysis is defined as the acceleration of a chemical reaction 3. if the amount of the enzyme is kept constant and the substrate concentration is then gradually increased, the reaction velocity will decrease. 4. In the Induced-fit Model, if a dissimilar substance which does not fit the site is present, the enzyme rejects it 5. The Michaelis constant Vo is defined as the substrate concentration at 1/2 the maximum velocity. 6. A prosthetic group - an organic substance which is dialyzable and thermostable which is firmly attached to the protein or apoenzyme portion. 7. The rate of an enzyme-catalyzed reaction increases as the temperature is raised beyond optimum temperature. 8. Enzymes can be classified by the kind of chemical reaction catalyzed. 9. The living cell is the site of tremendous…
Directions: Solve the following problem: The enzyme ẞ-methylaspartase catalyzes the deamination of ẞ-methylaspartate: CH,NH, CH OOC-CH-CH-COOOOC-CH-CH-COO+NH mesaconate Williams and Selbin The effects of hydroxymethylaspartate as an inhibitor for this enzyme was studied. The following data wer Substrate Concentration obtained: Reaction Rate without inhibitor (mM) 1 × 10-4 5 x 10-4 1.5 x 10-3 2.5 x 10-3 5 x 10-3 (mM/s) 0.026 0.092 0.136 0.150 0.165 Reaction Rate with inhibitor (mM/s) 0.010 0.040 0.086 0.120 0.142 Use Lineweaver-Burk plot to determine the KM and Vmax of the enzyme in the absence of inhibitor. Moreover, determine as well whether the inhibitor is competitive or noncompetitive. Show the graphs and calculations below.
1. The concentration of substrate X is high. What happens to the rate of the enzyme-catalyzed reaction if the concentration of substrate X is reduced? Explain. 2. An enzyme has an optimum pH of 7.2. What is most likely to happen to the activity of the enzyme if the pH drops to 6.2? Explain
Velocity (mmol/minute) [S], (mM) No inhibitor Inhibitor 3 10.4 4.1 5 14.5 6.4 10 22.5 11.3 30 33.8 22.6 90 40.5 33.8 The kinetics of an enzyme are measured as a function of substrate in the presence and the in absence of 2mM inhibitor (I). What are the values of Vmax and KM in the absence of inhibitor? In its presence? In its presence? What is the type of inhibition?
when saturated with substrate, an enzyme has a maximum initial rate of 110mumoles of substrate converted to product per second. At a substrate concentration of 100mu M, the same enzyme converts substrate to product at a rate of 0.010mmoles/ sec. Assuming that Michaelis - Menten kinetics are followed, calculate the reaction rate when substrate concentration is 2x10^-3M.
I. Indicate whether each of the following statements are true or false. _1. According to the lock-and-key model of enzyme action, the active site of an enzyme is flexible in shape. 2. In an enzyme-catalyzed reaction, the compound that undergoes a chemical change is called the substrate. 3. The nonprotein portion of a conjugated enzyme is the enzyme's active site. _4. Simple enzymes have inorganic cofactors, and conjugated enzymes have organic cofactors. 5. Vitamins are required in minute quantities for normal cellular function. 6. vitamins are found in all food groups. 7. Ribose sugars are found on one chain of the DNA molecule and deoxyribose sugars are found on the other chain of the DNA molecule. 8. A DNA molecule has a double helix at one end of the molecule and a single helix at the other end of the molecule. _9. Complementary bases are held together by covalent bonds. 10. DNA molecules always contain the nitrogenous base thymine.
1) 4 ms. Name an enzyme that requires NAD/NADH for activity. Draw the chemistry of this reaction (show mechanism).
1. The optimal conditions for salivary lysozyme (hydrolyzing glycoproteins ofbacterial wall) are 37 C- temperature and pH is 5.2. Explain the decrease in this enzyme activity if the temperature will rise up to 60 °C and pH will be changed to 8.0. To answer the question: a) draw the graph of the velocity dependency on temperature and pH; b) calculate the relative enzyme activity if 10 mg of lysozyme catalyzes the formation of 5 uM of the product per 2 minutes. 2 Consider the matic reaction schee: Asnaragine + H20 Aspartate+ NH3:
For an enzyme that displays Michaelis-Menton kinetics, what is thereaction velocity, V (as a percentage of V max , observed at the followingvalues?[S] = K M[S] = 0.5K M[S] = 0.1K M[S] = 2K M[S] = 10K M

SEE MORE QUESTIONS

Recommended textbooks for you

Biochemistry

ISBN:

9781319114671

Author:

Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:

W. H. Freeman

Lehninger Principles of Biochemistry

Biochemistry

ISBN:

9781464126116

Author:

David L. Nelson, Michael M. Cox

Publisher:

W. H. Freeman

Fundamentals of Biochemistry: Life at the Molecul…

Biochemistry

ISBN:

9781118918401

Author:

Donald Voet, Judith G. Voet, Charlotte W. Pratt

Publisher:

WILEY

Biochemistry

ISBN:

9781319114671

Author:

Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:

W. H. Freeman

Lehninger Principles of Biochemistry

Biochemistry

ISBN:

9781464126116

Author:

David L. Nelson, Michael M. Cox

Publisher:

W. H. Freeman

Fundamentals of Biochemistry: Life at the Molecul…

Biochemistry

ISBN:

9781118918401

Author:

Donald Voet, Judith G. Voet, Charlotte W. Pratt

Publisher:

WILEY

Biochemistry

ISBN:

9781305961135

Author:

Mary K. Campbell, Shawn O. Farrell, Owen M. McDougal

Publisher:

Cengage Learning

Biochemistry

ISBN:

9781305577206

Author:

Reginald H. Garrett, Charles M. Grisham

Publisher:

Cengage Learning

Fundamentals of General, Organic, and Biological …

Biochemistry

ISBN:

9780134015187

Author:

John E. McMurry, David S. Ballantine, Carl A. Hoeger, Virginia E. Peterson

Publisher:

PEARSON

SEE MORE TEXTBOOKS