Question

Strains X1120 and C11 are set up in a pairwise feeding experiment From the pathways below determine which strain is able to complete the pathway and describe how they are able to do so (be specific (5 pts) c Strain X1120 Gene 3 Gene 1 1 Enryme Enzyme Enzyme Substrate Strain C11 Gene 2 Gene 1 Enzyme Enzyme Enzyme Substrate

Answer 1

In the first strain as we can see substrate is acted upon by the enzyme A formed from the gene 1 and as everything is okay product A is formed. In the second step, A becomes the substrate on which enzyme B acts to form the product B, but as gene B is inactive. it won`t form the product B and as B will not be formed it will not be acted upon by the enzyme C formed from the gene C. Though gene C is active. Hence the final product will not be formed.

In the second case gene, 1 and gene 2 both are active hence they form their products A and B which completes the reaction till the formation of product B. But as gene 3 is not active, it will not form enzyme C which can act upon B to form the final reaction product.

Thus both the strains are incapable of forming the final product. Though the second strain is able to complete the pathway almost until the end.