Fe₃O₄ composited with MoS₂ blocks horizontal gene transfer

Area of Science:

• Environmental Science
• Microbiology
• Nanotechnology

Background:

• Horizontal gene transfer (HGT) is a significant mechanism for bacterial adaptation and spread of antimicrobial resistance.
• Iron oxide (Fe3O4) nanoparticles have been observed to promote HGT.
• The role of composite nanomaterials in modulating HGT remains largely unexplored.

Purpose of the Study:

• To investigate the effect of Fe3O4@MoS2 nanocomposites on HGT in bacterial conjugation systems.
• To elucidate the molecular mechanisms underlying the interaction between Fe3O4@MoS2 and bacteria concerning HGT.
• To explore the potential of Fe3O4@MoS2 as an environmentally friendly material for controlling HGT.

Main Methods:

• Quantitative Polymerase Chain Reaction (qPCR) was employed to analyze gene expression.
• The study focused on genes within the bacterial chromosome and plasmid involved in conjugation.
• Bacterial conjugation systems were utilized to assess HGT efficiency.

Main Results:

• Fe3O4 nanoparticles alone promoted HGT.
• Fe3O4@MoS2 nanocomposites significantly inhibited HGT during bacterial conjugation.
• Fe3O4@MoS2 altered the expression of key conjugation genes (trbA, traF, trbB, trfA, ompA, ompC), affecting cell membrane permeability and DNA uptake.
• MoS2 appeared crucial for the HGT-inhibiting properties of the composite.

Conclusions:

• Fe3O4@MoS2 nanocomposites effectively inhibit bacterial HGT by reducing cell membrane permeability.
• The findings highlight the potential of MoS2-containing nanomaterials for controlling the spread of genetic material in microbial communities.
• This research underscores the versatile biological applications of nanomaterials and guides the development of sustainable antimicrobial resistance control strategies.