Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Other Unique Bacteria01:18

Other Unique Bacteria

517
Magnetic bacteria exhibit a directed movement called magnetotaxis, driven by structures called magnetosomes. These magnetosomes consist of chains of magnetic particles made of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) and are organized in a linear conformation by a protein scaffold within invaginations of the cell membrane. The bacteria align along the north–south magnetic field lines, much like a compass needle. They are typically microaerophilic or anaerobic...
517
Metabolism of Chemolithotrophs01:15

Metabolism of Chemolithotrophs

1.1K
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.
1.1K
Inorganic Nitrogen Assimilation01:22

Inorganic Nitrogen Assimilation

712
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...
712
Microbial Nutrition01:28

Microbial Nutrition

1.7K
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...
1.7K
2° Amines to N-Nitrosamines: Reaction with NaNO201:20

2° Amines to N-Nitrosamines: Reaction with NaNO2

5.6K
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
5.6K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Prevalence of genetic variants in SERPINB2 and PKNOX1 genes in erythema nodosum leprosum patients from southern Brazil.

Journal of infection in developing countries·2025
Same author

UFSC Biotech Network: a transdisciplinary platform for biotechnology innovation in Brazil.

Trends in biotechnology·2025
Same author

How effective is biological activated carbon in removing micropollutants? A comprehensive review.

Journal of environmental management·2024
Same author

Inhibitory impact of the anticancer drug doxorubicin on anaerobic microbial community.

Aquatic toxicology (Amsterdam, Netherlands)·2023
Same author

Sarcoid reaction in eyebrow tattooing: a complication of a common cosmetic procedure.

Anais brasileiros de dermatologia·2023
Same author

Sensitizing agents found in children and adolescents with recalcitrant atopic dermatitis: a cross-sectional study with a pediatric battery.

Anais brasileiros de dermatologia·2022

Related Experiment Video

Updated: Mar 9, 2026

An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations
06:50

An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations

Published on: August 8, 2018

6.1K

Magnetite nanoparticles influence the ammonium-oxidizing bacteria activity during nitritation process.

Simone Perazzoli1, Camila Michels1, Hugo M Soares1

  • 1Department of Chemical and Food Engineering, Federal University of Santa Catarina, Florianópolis, SC 88034-001, Brazil

Water Science and Technology : a Journal of the International Association on Water Pollution Research
|January 10, 2017
PubMed
Summary

Commercial magnetite nanoparticles (Fe3O4-NPs) significantly inhibit ammonium-oxidizing bacteria (AOB) activity in wastewater treatment. Even short-term exposure to Fe3O4-NPs reduced nitrite production, with potential environmental implications via sludge disposal.

More Related Videos

Synthesis of Functionalized Magnetic Nanoparticles, Their Conjugation with the Siderophore Feroxamine and its Evaluation for Bacteria Detection
15:03

Synthesis of Functionalized Magnetic Nanoparticles, Their Conjugation with the Siderophore Feroxamine and its Evaluation for Bacteria Detection

Published on: June 16, 2020

10.0K
Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1
10:07

Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1

Published on: October 17, 2018

16.6K

Related Experiment Videos

Last Updated: Mar 9, 2026

An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations
06:50

An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations

Published on: August 8, 2018

6.1K
Synthesis of Functionalized Magnetic Nanoparticles, Their Conjugation with the Siderophore Feroxamine and its Evaluation for Bacteria Detection
15:03

Synthesis of Functionalized Magnetic Nanoparticles, Their Conjugation with the Siderophore Feroxamine and its Evaluation for Bacteria Detection

Published on: June 16, 2020

10.0K
Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1
10:07

Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1

Published on: October 17, 2018

16.6K

Area of Science:

  • Environmental Science
  • Nanotechnology
  • Environmental Chemistry

Background:

  • Nanomaterials (NMs) are increasingly released into the environment, potentially impacting wastewater treatment.
  • Iron oxide nanoparticles (Fe3O4-NPs) possess commercial value due to magnetic, catalytic, and antimicrobial properties.
  • Ammonium-oxidizing bacteria (AOB) are crucial for biological wastewater treatment and sensitive to contaminants.

Purpose of the Study:

  • To evaluate the impact of commercial magnetite nanoparticles (Fe3O4-NPs) on the activity of ammonium-oxidizing bacteria (AOB).
  • To determine the inhibitory effects and quantify the toxicity of Fe3O4-NPs on AOB in a simulated wastewater treatment environment.

Main Methods:

  • Kinetic experiments exposing AOB to various concentrations of Fe3O4-NPs (0.2–1.0 g L⁻¹) for 14 hours.
  • Measurement of nitrite-nitrogen (NO2⁻-N) production rates to assess AOB activity.
  • Scanning electron microscopy (SEM) to visualize Fe3O4-NPs interaction with microbial biomass.

Main Results:

  • A significant decrease in NO2⁻-N production rate (up to 61.33%) was observed at the highest Fe3O4-NP concentration compared to controls.
  • The estimated half-maximal inhibitory concentration (IC-50) for Fe3O4-NPs on AOB activity was 0.483 g L⁻¹.
  • SEM images confirmed the incorporation of Fe3O4-NPs within the wastewater sludge biomass.

Conclusions:

  • Fe3O4-NPs exhibit inhibitory effects on AOB, compromising a key step in biological wastewater treatment.
  • The accumulation of Fe3O4-NPs in sludge suggests potential environmental dissemination through sludge disposal, particularly for agricultural reuse.
  • Further research is needed to understand the long-term ecological consequences of NP contamination in wastewater treatment systems.