Biology 9700 · AS & A Level · Principles of genetic technology
Principles of genetic technology — practice question
Gold ions ($\text{Au}^{3+}$) are poisonous to most microorganisms. Even so, the bacterium \emph{Delftia acidovorans} is often present in slimy coatings, known as biofilms, that develop on the surfaces of gold deposits. \emph{D. acidovorans} makes a peptide synthase that catalyses the synthesis of a small peptide called delftibactin. Once isolated, delftibactin can cause $\text{Au}^{3+}$ ions to precipitate as tiny particles of metallic gold. Delftibactin is a secondary metabolite.
(a)[3]
Name a different secondary metabolite and explain what the term means.
(b)[3]
With reference to Fig. 2.1, suggest how delftibactin may protect \emph{D. acidovorans} from toxic $\text{Au}^{3+}$ ions.
(c)[4]
Explain whether or not the results shown in Fig. 2.2 support the view that delftibactin is protective.
(d)[5]
Describe how delftibactin could be manufactured on a large scale.
Worked solution & mark scheme
This 15-mark question has a full step-by-step worked solution and mark scheme. One marking point: “penicillin or any other named antibiotic” …