Part A - Order of substrates in biochemical pathway The problem below relates to
ID: 96061 • Letter: P
Question
Part A - Order of substrates in biochemical pathway
The problem below relates to the synthesis of several intermediates in a biochemical pathway, which is essential for growth and survival. A set of experimental results relating the growth (+) of Neurospora auxotroph strains on several media is given in the table. The inability of an auxotroph strain to grown on specific media is shown by the (-) symbol.
Media abbreviations
MM = minimal medium. Different intermediates are added to this medium: O = oxaloacetate, F = fumarate, M = malate, and S = succinate.
Based on the information provided, present the biochemical pathway for the substances oxaloacetate, fumarate, malate, and succinate. When you answer this pathway, simply list the order of the letters for each intermediate in the pathway with no spaces in between (e.g., OFMS).
Strain Medium
MM MM+O MM+F MM+M MM+S
a - + - + -
b - + - - -
c - + + + -
Part B - Biochemical activity of proteins encoded by auxotroph strains
Based on the data shown in the table above, determine the order in which these loci act. Each mutant strain contains a mutated gene that encodes a protein that catalyzes a step in the biochemical pathway you determined in PartA. These proteins catalyze the conversion of intermediates in the biochemical pathway. Report the order these loci act in the pathway from the beginning of the pathway to the end. When you answer this, simply list the order of the letters for each enzyme in the pathway with no spaces in between (e.g., abc).
Explanation / Answer
The order of intermediates in the Kreb's cycle is succinate, fumarate, maltate and oxaloacetate. This is represented by the letters SFMO.
The order of mutants in the pathway is 'cab'.