Chapter 8

Last update by mayur on 03/27/2014
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In order to attach a particular amino acid to the tRNA molecule that will transport it, anenzyme, an aminoacyl-tRNA synthetase, is required, along with ATP. Initially, the enzyme hasan active site for ATP and another for the amino acid, but it is not able to attach the tRNA. Whatmust occur in order for the final attachment to occur?

A) The ATP must first have to attach to the tRNA.

B) The binding of the first two molecules must cause a 3-dimensional change that opens anotheractive site on the enzyme.

C) The hydrolysis of the ATP must be needed to allow the amino acid to bind to the synthetase.

D) The tRNA molecule must have to alter its shape in order to be able to fit into the active sitewith the other twomolecules.

E) The 3' end of the tRNA must have to be cleaved before it can have an attached amino acid.

Answer:

B) The binding of the first two molecules must cause a 3-dimensional change that opens anotheractive site on the enzyme.



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