It is possible to isolate mutant bacteria that are phenylalanine auxotrophs, that is they require
phenylalanine in the medium in order to grow: non-mutant bacteria, of course, are able to
synthesize their own phenylalanine via the shikimate pathway. A phenylalanine auxotroph (with
one mutation in the shikimate pathway) is able to grow well in the presence of phenylalanine, but
as soon as the added phenylalanine is used up, these bacteria stop growing and begin to excrete a
metabolite of the shikimate pathway. Explain in detail why these bacteria don\'t begin to excrete
this metabolite before using up the phenylalanine in the medium.
Solution
Phenylalanine is transformed into norepinephrine in the body through a variety of metabolic
steps, as well as to other active chemicals, such as epinephrine, dopamine, and tyramine.
Norepinephrine is an important neurotransmitter that conveys information from nerve to nerve
and is apparently important for memory, alertness, and learning.
Practitioners recommend phenylalanine for treatment of depression, bipolar disorder,
hyperactivity, and Parkinson.
It is possible to isolate mutant bacteria that are phenylalanine aux.pdf
1. It is possible to isolate mutant bacteria that are phenylalanine auxotrophs, that is they require
phenylalanine in the medium in order to grow: non-mutant bacteria, of course, are able to
synthesize their own phenylalanine via the shikimate pathway. A phenylalanine auxotroph (with
one mutation in the shikimate pathway) is able to grow well in the presence of phenylalanine, but
as soon as the added phenylalanine is used up, these bacteria stop growing and begin to excrete a
metabolite of the shikimate pathway. Explain in detail why these bacteria don't begin to excrete
this metabolite before using up the phenylalanine in the medium.
Solution
Phenylalanine is transformed into norepinephrine in the body through a variety of metabolic
steps, as well as to other active chemicals, such as epinephrine, dopamine, and tyramine.
Norepinephrine is an important neurotransmitter that conveys information from nerve to nerve
and is apparently important for memory, alertness, and learning.
Practitioners recommend phenylalanine for treatment of depression, bipolar disorder,
hyperactivity, and Parkinson
