Related Experiment Video
Updated: Sep 19, 2025
08:13
A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
17.2K
High-efficiency nitrogen removal by cold-tolerant bacteria consortium at low temperatures
Yilin Xu1, Nyambane Clive Ontita1, Weimin Zeng2
1School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China.
Bioresource Technology
|June 16, 2025
Summary
A novel cold-tolerant bacteria consortium (M2) effectively removes nitrogen in wastewater treatment at low temperatures. This breakthrough addresses a key challenge for cold-climate regions, improving winter wastewater management.
Area of Science:
- Environmental Microbiology
- Wastewater Treatment Engineering
Background:
- Wastewater treatment processes struggle with reduced nitrogen removal efficiency at low temperatures (< 15 °C).
- Cold-induced stress negatively impacts microbial consortia responsible for nitrogen cycling.
Purpose of the Study:
- To develop and evaluate a cold-tolerant bacteria consortium (M2) for enhanced nitrogen removal in low-temperature wastewater treatment.
- To investigate the mechanisms behind M2's resilience and efficiency under cold stress.
Main Methods:
- Development of a cold-tolerant bacteria consortium (M2).
- Assessment of nitrogen removal efficiencies (NH4+-N, NO3--N, NO2--N) at low temperatures.
- Analysis of microbial community composition (dominant genera).
- Metagenomic analysis to identify cold-resilience genes and pathways.
Main Results:
- Consortium M2 achieved high nitrogen removal efficiencies: 97.34% for NH4+-N, 97.13% for NO3--N, and 59.92% for NO2--N.
- M2 is dominated by Comamonas, Pseudomonas, and Acinetobacter, producing extracellular polymeric substances (EPS) and unsaturated fatty acids.
- Metagenomic analysis revealed cold-shock responsive genes (e.g., unsaturated fatty acid synthase, cpsA) contributing to cold resilience.
- M2 demonstrated enhanced nitrogen assimilation and nitrate reduction under cold stress.
Conclusions:
- The cold-tolerant bacteria consortium M2 offers a practical solution for improving nitrogen removal in wastewater treatment during winter.
- M2's resilience is attributed to EPS production, unsaturated fatty acids, and specific cold-shock responsive genes.
- This strategy effectively addresses operational limitations in cold-climate wastewater management.
More Related Videos
08:05Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
6.2K
09:05Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials
Published on: May 15, 2015
14.9K
Related Concept Videos
01:21Hyperthermophilic Bacteria
114
Domain Bacteria includes some unique hyperthermophilic species. They exhibit remarkable adaptations that enable survival in extreme environments.Thermotoga species are rod-shaped, gram-negative, non-sporulating hyperthermophiles that form a sheath-like envelope called a toga. They ferment sugars or starch, producing lactate, acetate, CO₂, and H₂, and can also grow via anaerobic respiration using H₂ and ferric iron. Found in hot springs and hydrothermal vents, over 20% of their...
114
01:28Carbon-dioxide Fixation
94
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...
94
01:15Metabolism of Chemolithotrophs
192
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.
192
01:22Inorganic Nitrogen Assimilation
118
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...
118
01:27Factors Influencing Microbial Growth: Temperature
265
Microorganisms display remarkable adaptations, enabling them to thrive in diverse ecological niches across a wide range of temperatures. Temperature profoundly influences microbial growth by affecting enzymatic activity, membrane fluidity, and other cellular processes.Each microorganism operates within a specific temperature range defined by three cardinal points: minimum, optimum, and maximum. Below the minimum temperature, membranes lose fluidity, halting transport processes. Above the...
265
01:30Environmental Applications of Microorganisms
302
Microorganisms play a pivotal role in maintaining ecosystem balance by recycling essential elements such as carbon, nitrogen, and phosphorus, as well as supporting processes like bioremediation, wastewater treatment, and biofuel production.Microbes in Elemental CyclesIn the carbon cycle, microorganisms decompose organic matter, releasing carbon dioxide via aerobic respiration. This carbon dioxide is subsequently used by photosynthetic organisms to synthesize organic compounds, closing the...
302