Which of the following bacteria preferentially accumulate phosphorus from water and are used in microbial phosphorus removal processes?

Correct option is C

1. Acinetobacter:
· Correct.
· Acinetobacter species are well-known for their role in biological phosphorus removal processes in wastewater treatment.
· They accumulate phosphorus as polyphosphate granules inside their cells, which are later removed as sludge.
2. Achromobacter:
· Not primarily involved in phosphorus accumulation. It is more associated with nitrogen removal and other metabolic processes.
3. Serratia:
· Serratia species are opportunistic pathogens and not typically used in wastewater treatment for phosphorus removal.
4. Nitrobacter:
· Nitrobacter is primarily involved in the nitrogen cycle, converting nitrite (NO2−​) to nitrate (NO3−​), but it does not play a significant role in phosphorus removal.
Thus, the correct answer is (3) Acinetobacter.
Information Booster: 1. Phosphorus Removal in Wastewater:
· Excess phosphorus leads to eutrophication in water bodies, causing algal blooms and oxygen depletion.
· Biological phosphorus removal involves polyphosphate-accumulating organisms (PAOs), like Acinetobacter.
2. Process of Biological Phosphorus Removal:
· Anaerobic Phase: PAOs release phosphorus into the water and store volatile fatty acids as polyhydroxyalkanoates (PHAs).
· Aerobic Phase: PAOs take up excess phosphorus and store it as intracellular polyphosphate.
3. Key PAOs:
· Acinetobacter
· Rhodocyclus
· Defluviicoccus
Additional Knowledge: · Role of Acinetobacter:
· Known as a polyphosphate-accumulating organism.
· Widely used in enhanced biological phosphorus removal (EBPR) systems.
· Other Wastewater Bacteria:
· Nitrobacter: Important for nitrification (nitrite to nitrate).
· Pseudomonas: Plays a role in denitrification.
· Thiothrix: Helps in filamentous sludge bulking.
· Eutrophication Control:
· Reduction of phosphorus is critical for preventing eutrophication. Biological processes are environmentally friendly compared to chemical methods.