A new sugar, sugarose, induces synthesis of two enzymes from the sug operon of E. coli. Some properties of mutants with a deletion in the following genes affecting the appearance of these enzymes are as follows (here, ?+?= enzyme induced normally, i.e., synthesized only in the presence of the inducer; C = enzyme synthesized constitutively; 0 = enzyme cannot be detected):

Mutation of	Enzyme 1	Enzyme 2
Gene A	+	0
Gene B	0	+
Gene C	0	0
Gene D	C	C

a. The genes are adjacent, in the order A B C D. Which gene is most likely to be the structural gene for enzyme 1?

b. From all the evidence given, determine whether the following statements are true or false:

i. It is possible that gene D is a structural gene for one of the two enzymes.

ii. It is possible that gene D produces a repressor.

iii. It is possible that gene D produces a cytoplasmic product required to induce production of enzymes 1 and 2.

iv. It is possible that gene D is an operator locus for the sug operon.

v. It is possible that gene C could be a gene that produces a cytoplasmic factor that is required to induce enzymes 1 and 2.

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a Based on the given data gene B is most likely to be the structural gene for enzyme 1 This is becau... View the full answer