Temperature-sensitive mutations (ts) in E. coli are a type of conditional lethal mutation. A conditional lethal...

Temperature-sensitive mutations (ts) in E. coli are a type of conditional lethal mutation. A conditional lethal means that the mutation is only deadly under certain growth conditions, in this case when the temperature is increased to the restrictive temperature. The proteins are fully functional at the lower temperature (permissive). This type of mutation has been indispensable for studying the essential process of DNA replication. Mutants in proteins that are necessary for DNA replication can be classified into either quick-stop or slow-stop. Quick-stop mutants arrest DNA replication immediately, but slow-stop mutants halt after several minutes. Fill in the chart below to indicate which mutations will be slow and which quick when shifted to the higher, restrictive temperature. Assume that the E. coli have already started replication. Explain your answers. (6pts total: 1.5pts each)

Mutated Protein	Quick or slow?	Explanation
DNA gyrase
DnaA
DNA helicase
DNA ligase

Expert Solution

gladiator answered 7 months ago

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