The presence of genes encoding RubisCO enzymes in Methanocaldococcus jannaschii and a species of Pyrococcus indicates that the organisms
A) incorporate carbon dioxide via the acetyl-CoA pathway.
B) incorporate carbon dioxide via the Calvin cycle.
C) incorporate carbon dioxide via the reverse citric acid cycle.
D) utilize molecular hydrogen as an electron donor in chemolithotrophic metabolism.

Question

Quizplus · Accepted Answer

The presence of genes encoding RubisCO enzymes in Methanocaldococcus jannaschii and a species of Pyrococcus indicates that the organisms incorporate carbon dioxide via the Calvin cycle, a process that is involved in carbon fixation in photosynthetic organisms. RubisCO enzyme is essential in fixing inorganic carbon (CO2) into organic (sugar) molecules by catalyzing the first step of the Calvin cycle, which involves the carboxylation of ribulose-1,5-bisphosphate (RuBP).

The Presence of Genes Encoding RubisCO Enzymes in Methanocaldococcus Jannaschii