Exam 7: Enzyme Mechanisms

What is the appropriate order of the following steps? A.Glutamine binding to uridylyltransferase B.Adenylation of glutamine synthetase C.Deuridylation of glutamine synthetase adenylyltransferase

If the rate constant for a reaction is determined to be equal to v / [Q][R],the reaction is the conversion of

In the formation of an ESI complex,__________ inhibition can result.

An enzyme is crystallized in preparation for X-ray crystallography.The crystal is then soaked in a solution of substrate and the crystal shatters.Propose a reason for this result.

What is Henry Eyring's transition state theory?

Hexokinase catalyzes the first step of glycolysis,which occurs in the cell cytoplasm.The protocol for an in vitro enzyme activity assay of hexokinase suggests that the assay is carried out at a pH of 7.4.Predict what may occur if the assay is carried out at a pH of 8.8 instead.Explain your reasoning.

A kinase adds a phosphate group to a target enzyme,altering the catalytic efficiency of the enzyme.This is an example of

Using words,define initial velocity (v₀)for an enzyme-catalyzed reaction.

Enzymes usually bind substrates with __________ affinity and __________ specificity.

Complete the following statement: The NH groups of Ser195 and Gly193 in chymotrypsin are able to stabilize the intermediate of the reaction by

If an enzyme carries out acid-base catalysis,which of the following amino acids could act as general acid?

The side chains of the amino acids that make up the catalytic triad of chymotrypsin contain all EXCEPT

Which type of reaction does not change the molecular formula of the product compared with that of the substrate?

A mutation results in the change of Ser to Asp in the substrate binding pocket of chymotrypsin.Most likely,the mutant enzyme will

Acetylcholinesterase is an important enzyme in the nervous system.Acetylcholinesterase activity is blocked by the nerve agent sarin gas,which forms a covalent bond with a Ser in the active site of the enzyme.Sarin gas is a(n)

Which pair correctly matches the coenzymes most often used to mediate the described redox reactions?

Nitrite reductase contains two histidine amino acids that coordinate a Cu²⁺ ion.When the ion is present in the enzyme,the ion is a __________ and the enzyme is a __________.

Which of the following is true of a coenzyme but NOT true of a prosthetic group?

Given the following parameters,calculate K_m.

An enzyme can increase the rate of a reaction inside a cell by __________ the energy of the __________.