Assume in Neurospora that there are six different histidine-deficient mutants, a

Question

Assume in Neurospora that there are six different histidine-deficient mutants, all mutational lesions in different genes. When tested on a number of minimal media, each one supplemented with a single possible precursor to histidine, the growth pattern shown in the table below is observed, where plus (+) indicates growth. Part A Determine the order in which the precursors occur in the synthesis of this amino acid and the step that is affected in each mutant. List the precursors in the order in which they appear in the biosynthetic pathway, from first to last. Indicate the mutant that affects each step by including its number in the proper position. Use capital letters for the precursors. Do NOT include any spaces. For example: 1A2B3C4D5E6 would indicate that A is the first precursor, E is the last, and mutant 1 disrupts the step that produces A, mutant 3 affects the step that converts B to C, and mutant 6 affects the step that converts mutant E to His (do not add the endproduct (His) to your answer -- it should already be to the right in your answer box).

Explanation / Answer

The order of the substrates is A--> B -->C --> D--> E--> Histidine

A mutation in the gene that converts E to Histine leads to accumulation of the substrate E.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.