I. Given the following partial diploids in E coli accomplished via sexduction wi

ID: 176322 • Letter: I

Question

I. Given the following partial diploids in E coli accomplished via sexduction with the F plasmid, tell which functional enzymes will be expressed under the conditions noted ithe table. Use a large to indicate transcription of functional enzymes and a large to idicate no transcription or transcription of non-functional enzymes. The -d genotype results in defective repressor polypeptide subunits. The repressor protein i a tetramer with structure. These -d mutant subunits combine with each other or wild-type and interfere with their function and therefore cannot bind the operator Assume that trpR binds trpo without trp. 16 pts

Explanation / Answer

Trp E is involved in production of Anthranilate synthase so mutation in trpE won’t produce Anthranilate synthase.

TrpA is involved in production of Trp synthase so mutation in trpE won’t produce Trp synthase

In absence or mutation of trpR =repressor, production of enzymes cannot be regulated whether tryptophan present or absent.

Genotype

Low level tryptophan for Anthranilate synthase

Low level tryptophan for Trp synthase

High level tryptophan for Anthranilate synthase

High level tryptophan for Trp synthase

I/II

+/-

III/IV

-/+

+/-

-/-

+/-

V/VI

-/+

+/+

-/-

+/-

VII/VIII

-/+

+/-

-/-