Consider the chemical reactions of the sulfur cycle shown in Figure 26.10. Reduction of CO₂ to generate carbohydrates can occur when coupled to the oxidation of reduced sulfur compounds (e.g., H₂S). This latter process is carried out by what type of microorganism(s)?

Question

Quizplus · Accepted Answer

Purple bacteria are known to carry out the oxidation of reduced sulfur compounds, such as hydrogen sulfide, in order to generate energy and fix carbon dioxide into carbohydrates. This process is known as anoxygenic photosynthesis, as it does not produce oxygen as a byproduct. Cyanobacteria, on the other hand, carry out oxygenic photosynthesis and do not typically participate in sulfur oxidation-reduction reactions.

Consider the Chemical Reactions of the Sulfur Cycle Shown in Figure