A classic way to isolate thymidylate synthase–negative mutants of bacteriais to treat a growing culture with thymidine and trimethoprim. Most ofthe cells are killed, and the survivors are greatly enriched in thymidylatesynthase–negative mutants.(a) What phenotype would allow you to identify these mutants?(b) What is the biochemical rationale for the selection? (That is, why are themutants not killed under these conditions?)(c) How would the procedure need to be modified to select mammalian cellmutants defective in thymidylate synthase?

A classic way to isolate thymidylate synthase–negative mutants of bacteriais to treat a growing culture with thymidine and trimethoprim. Most ofthe cells are killed, and the survivors are greatly enriched in thymidylatesynthase–negative mutants.(a) What phenotype would allow you to identify these mutants?(b) What is the biochemical rationale for the selection? (That is, why are themutants not killed under these conditions?)(c) How would the procedure need to be modified to select mammalian cellmutants defective in thymidylate synthase?

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter10: From Proteins To Phenotypes

Section: Chapter Questions

Problem 10QP: b. Compounds A, B, C, and D are known to be intermediates in the pathway for production of protein...

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