2. The pathways for the biosynthesis of the amino acidsglutamine (Gln) and proline (Pro) involve one or morecommon intermediates. Auxotrophic yeast mutantsnumbered 1–7 are isolated that require either glutamine or proline or both amino acids for their growth,as shown in the following table (+ means growth; −no growth). These mutants are also tested for theirability to grow on the intermediates A–E. What is theorder of these intermediates in the glutamine and proline pathways, and at which point in the pathways iseach mutant blocked?Gln +Mutant A B C D E Gln Pro Pro1 + − − − + − + +2 − − − − − − + +3 − − + − − − − +4 − − − − − + − +5 − − + + − − − +6 + − − − − − + +7 − + − − − + − +

2. The pathways for the biosynthesis of the amino acidsglutamine (Gln) and proline (Pro) involve one or morecommon intermediates. Auxotrophic yeast mutantsnumbered 1–7 are isolated that require either glutamine or proline or both amino acids for their growth,as shown in the following table (+ means growth; −no growth). These mutants are also tested for theirability to grow on the intermediates A–E. What is theorder of these intermediates in the glutamine and proline pathways, and at which point in the pathways iseach mutant blocked?Gln +Mutant A B C D E Gln Pro Pro1 + − − − + − + +2 − − − − − − + +3 − − + − − − − +4 − − − − − + − +5 − − + + − − − +6 + − − − − − + +7 − + − − − + − +

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter35: Plant Nutrition

Section: Chapter Questions

Problem 7TYK

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1. Which of the following pathways of information flow has never been observed on Earth? chose all that apply a. From RNA to DNA b. From RNA to Protein c. From DNA to RNA d. From Protein to RNA e. From Protein to DNA f. From DNA to Protein 2. Which biosynthetic pathways are downregulated by the products of the de novo purine biosynthesis pathway? Choose all that apply a. The de novo pyrimidine biosynthesis pathway b. The pyrimidine salvage pathway c. The pathway to 5-phosphoribose-1-pyrophosphate (PRPP) d. The de novo purine biosynthesis pathway e. The pathway to the amino acid histidine f. The purine salvage pathway
The intermediates A, B, C, D, E, and F all occur inthe same biochemical pathway. G is the product of thepathway, and mutants 1 through 7 are all G−, meaningthat they cannot produce substance G. The followingtable shows which intermediates will promote growthin each of the mutants. Arrange the intermediates inorder of their occurrence in the pathway, and indicatethe step in the pathway at which each mutant strain isblocked. A + in the table indicates that the strain willgrow if given that substance, an O means lack of growth.SupplementsMutant A B C D E F G1 + + + + + O +2 O O O O O O +3 O + + O + O +4 O + O O + O +5 + + + O + O +6 + + + + + + +7 O O O O + O +
When present on the leaves of plants, the bacterium Pseudomonas syringae can promote frost damage to plants. Mutant strains, lacking the “ice” gene, have been applied to plants to try and protect the plants from wild-type P. syringae-induced frost. Assume that I am telling the truth that wild-type P. syringae nucleates ice formation at -2 °C, and provide an explanation as to why application of this altered (mutant) bacterium to plants might be a beneficial agricultural strategy in areas where morning lows occasionally dip down to 28-30 °F.
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For the study of alanine production by a recombinant strain of E. coli, cultivation was carried out in a benchtop bioreactor with 4.5 L of culture medium, using glucose as a limiting substrate. During the cultivation, there was no lag phase and the cells showed exponential growth for 5 hours. The following table presents the results of the analysis of ammonia and glucose consumption, and alanine accumulation throughout the cultivation. Knowing that 500 mL of a cell suspension at a concentration of 5.0 g/L (inoculum) was added to the 4.5 L of medium in the reactor and that the YX/NH3 previously determined was 7.5, calculate:a) the maximum specific growth rateb) YX/S and YP/S yield factorsc) How long would it take to reach Cx = 30 g/L if the cells continued with the exponential growth profile until the end of the culture (without nutrient deprivation or any type of inhibition)?d) Describe how the mathematical treatment of the data should be done to determine the type of product formation…
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