Problem:
An E. coli mutant was isolated that could not grow with glucose as the sole carbon source. Upon examination it was found that the mutant had a defective HPr protein.
Required:
Question 1: Why would a defective HPr lead to this phenotype?
Question 2: In addition to not being able to use glucose as a carbon source, this mutant grew poorly in the presence of lactose or arabinose. Provide an explanation for this observation.
Could someone help to explain the answer of these questions.