Iron redox-driven efficient nitrification-denitrification by Acinetobacter nosocomialis C24
Zongjian Huang1, Siqi Yang2, Liyi Pan1
1College of Food Science, South China Agricultural University, Guangzhou, 510642, China.
Journal of Environmental Management
|June 2, 2026
Summary
Iron (Fe3+/Fe2+) addition significantly boosted Acinetobacter nosocomialis C24
Area of Science:
- Environmental Microbiology
- Biotechnology
- Wastewater Treatment
Background:
- Simultaneous nitrification-denitrification and phosphate removal (SNDPR) is vital for efficient wastewater treatment.
- Developing single-reactor aerobic systems requires effective SNDPR strategies.
Purpose of the Study:
- To investigate the enhancement of SNDPR by Acinetobacter nosocomialis C24 using Fe3+/Fe2+.
- To elucidate the underlying mechanisms of Fe3+/Fe2+ mediated enhancement.
Main Methods:
- Microbial cultivation and performance evaluation of Acinetobacter nosocomialis C24.
- Analysis of nutrient removal efficiencies (NH4+-N, PO43--P, TN).
- Genomic and transcriptomic analyses to understand metabolic pathways.
Main Results:
- Fe3+/Fe2+ addition increased NH4+-N and PO43--P removal by 33.1% and 26.9% within 24 hours.
- Strain C24 achieved >92% removal of total nitrogen (TN) and phosphate (PO43--P) under mixed conditions.
- Fe3+/Fe2+ stimulated extracellular polymeric substance (EPS) production, correlating with TN removal.
Conclusions:
- Fe3+/Fe2+ significantly enhances SNDPR in Acinetobacter nosocomialis C24.
- The study reveals Fe3+/Fe2+ influences iron redox, carbon, and nitrogen metabolism via DNRA.
- A. nosocomialis C24 is a promising candidate for advanced wastewater treatment.
Related Concept Videos
Metabolism of Chemolithotrophs
Chemolithotrophs are microorganisms that obtain energy by oxidizing inorganic molecules such as hydrogen gas (H₂), ammonia (NH₃), reduced sulfur compounds (H₂S, S²⁻), and ferrous iron (Fe²⁺). Unlike heterotrophic organisms that rely on organic carbon, chemolithotrophs transfer electrons from these inorganic donors to the electron transport chain (ETC), generating a proton motive force (PMF) that drives ATP synthesis through oxidative phosphorylation. However, because inorganic electron donors...
Inorganic Nitrogen Assimilation
Nitrogen is an essential element in biological systems, forming a crucial component of proteins, nucleic acids, and other cellular constituents. Many bacteria and archaea acquire nitrogen in the form of nitrate (NO₃⁻) or ammonia (NH₃), which are then assimilated into biomolecules through specific enzymatic pathways.Assimilatory Nitrate ReductionWhen nitrate enters the cell, it undergoes a two-step reduction process known as assimilatory nitrate reduction. Initially, the enzyme nitrate reductase...
Microbial Nutrition
Organisms exhibit remarkable metabolic diversity, categorized based on how they acquire energy and carbon. These strategies enable survival in various ecological niches and are essential for maintaining energy flow and nutrient cycling within ecosystems.Energy and Carbon SourcesOrganisms are classified as phototrophs or chemotrophs based on energy acquisition. Phototrophs use light as their energy source, while chemotrophs rely on oxidizing chemical compounds. Further differentiation arises...
Microbes and the Nitrogen Cycle
The nitrogen cycle is a complex biogeochemical process critical to maintaining the balance of nitrogenous compounds in ecosystems. This cycle involves multiple microbial-mediated transformations through which nitrogen changes oxidation states, supporting essential ecological functions and contributing to plant and microbial growth.Nitrogen Fixation and AmmonificationNitrogen fixation initiates the cycle by converting inert atmospheric nitrogen (N₂) into bioavailable ammonia (NH₃), a process...
Microbes and Other Elemental Cycles
Microbial activity plays a pivotal role in the biogeochemical cycling of iron and manganese, especially at the redox gradients characteristic of stratified aquatic environments. These cycles are driven by microbial transformations between oxidized and reduced forms of the metals, allowing organisms to exploit them for metabolic energy and structural purposes.Iron Cycling Across Redox GradientsIn neutral, oxygen-rich surface waters, iron is predominantly found in its oxidized, insoluble ferric...
Carbon-dioxide Fixation
Carbon dioxide fixation in prokaryotes enables the assimilation of inorganic carbon into organic molecules, supporting biosynthetic pathways, sustaining ecosystems, and contributing to the global carbon cycle. It also has industrial applications in carbon capture and bioproduct synthesis. Autotrophic organisms rely on this process to utilize CO₂ as a carbon source in diverse environments.The Calvin CycleThe Calvin cycle is the most widespread carbon fixation mechanism, primarily used by...


