Chapter 18, Problem 16P

Some ts alleles are temperature sensitive during protein synthesis: If translation occurs at the restrictive temperature, the newly forming protein cannot fold correctly. Other ts alleles are temperature sensitive for activity: When the temperature is raised, the existing, properly folded protein unfolds and can no longer perform its function. Which kind of ts allele is better for temperature shift experiments like the one in Fig. 18.12 (p. 608) aimed at determining when a protein functions? Explain your answer.