Answer:
D is the correct Answer
Explanation:
it is D because there is a difference bewtween them so watch what you selected please
Answer and explanation;
-Aba is a suitable replacement because Aba and Cys have approximately the same sized side chain and are similarly hydrophobic.
-However, Aba cannot form disulfide bonds so it will not be a suitable replacement if these are required.
-Alpha-Aminobutyric acid is biosynthesized by transaminating oxobutyrate, a metabolite in isoleucine biosynthesis.
Most, maybe all, bacteria have their genome DNA tethered to their cell membranes, so it is in the cytoplasm but its not really floating around. Plasmids in bacteria however are free floating. This is why it's so easy to isolate plasmids from bacteria with centrifugation after lysing.