# Molecular mechanism of gallium nitrate in inhibiting bacterial biofilm formation through pykF modulation

**Authors:** Xiaofeng Zhang, Junjie Dong, Bing Wang, Lingqiang Chen, Zhiqiang Gong, Jin Yang, Guizhao Shu, Qi Ning, Irene Ling, Irene Ling, Irene Ling, Irene Ling, Irene Ling

PMC · DOI: 10.1371/journal.pone.0337557 · 2026-03-06

## TL;DR

Gallium nitrate inhibits bacterial biofilm formation by upregulating pyruvate kinase (pykF), offering a potential strategy for treating biofilm-related infections.

## Contribution

This study identifies pykF as a key target of gallium nitrate in suppressing bacterial biofilms and virulence.

## Key findings

- Gallium nitrate suppresses biofilm formation and metabolic activity in bacteria.
- Upregulation of pykF is strongly associated with gallium's antibacterial effects.
- PykF knockout increases bacterial survival and biofilm formation, highlighting its role in gallium's mechanism.

## Abstract

Gallium nitrate, a non-redox analog of iron (III), suppresses bacterial biofilms and virulence within the framework of bacterial regulation. This study investigates the molecular mechanisms and regulatory pathways through which gallium nitrate modulates bacterial activity and function.

The antimicrobial properties of gallium nitrate, its effects on bacterial biofilms, and gallium-responsive signaling pathways were assessed. Observation of marked upregulation of pyruvate kinase (pykF) expression following gallium nitrate exposure prompted in vitro and in vivo experiments to examine how gallium influences the expression, enzymatic activity, and functional role of bacterial pykF.

Crystal violet staining, XTT assay, confocal laser scanning microscopy, and scanning electron microscopy consistently indicated that gallium nitrate suppressed bacterial biofilm formation and metabolic activity. Transcriptomic profiling and subsequent validation analyses further suggested a strong association between pykF and gallium-mediated antibacterial effects. Both in vitro and in vivo experiments revealed that pykF knockout significantly enhanced bacterial survival and biofilm formation.

Gallium nitrate modulates bacterial biofilm development and virulence, with its antimicrobial effect largely dependent on pykF upregulation. Concurrent therapeutic targeting of both pykF and gallium may provide a more effective strategy against persistent biofilm-associated infections. This work also establishes a mechanistic basis for clinical approaches aimed at reducing biofilm formation and limiting device-related infections.

## Linked entities

- **Genes:** pykF (pyruvate kinase) [NCBI Gene 881682]
- **Chemicals:** gallium nitrate (PubChem CID 61635)

## Full-text entities

- **Diseases:** intraosseous infection (MESH:C564648), Capsular contracture (MESH:D003286), CLSM (MESH:D004401), inflammatory (MESH:D007249), necrosis (MESH:D009336), chronic pain (MESH:D059350), bacterial bone infections (MESH:D001424), nonunion (MESH:C538144), osteomyelitis (MESH:D010019), Infection (MESH:D007239), cytotoxicity (MESH:D064420), bone defects (MESH:D001847)
- **Chemicals:** sodium dodecyl sulfate (MESH:D012967), copper (MESH:D003300), Gallium nitrate (MESH:C027235), silver (MESH:D012834), ethanol (MESH:D000431), methicillin (MESH:D008712), PEP (MESH:D010728), water (MESH:D014867), TRIzol (MESH:C411644), Fe-S (MESH:D007501), nitrogen (MESH:D009584), pentose phosphate (MESH:D010428), carbon (MESH:D002244), agar (MESH:D000362), saline (MESH:D012965), lentinan (MESH:D007912), pyruvate (MESH:D019289), metal (MESH:D008670), osmium tetroxide (MESH:D009993), zinc (MESH:D015032), nitrate (MESH:D009566), polyvinylidene fluoride (MESH:C024865), Gallium citrate (MESH:C103850), NAD+ (MESH:D009243), GA (MESH:D005708), eosin (MESH:D004801), acetate (MESH:D000085), glutaraldehyde (MESH:D005976), argon (MESH:D001128), glucose (MESH:D005947), TiO2 (MESH:C009495), 4-hydroxyisoleucine (MESH:C104672), ATP (MESH:D000255), Polydimethylsiloxane (MESH:C013830), paraformaldehyde (MESH:C003043), amino acid (MESH:D000596), titanium (MESH:D014025), dUTP (MESH:C027078), oxaloacetate (MESH:D062907), acetone (MESH:D000096), H&amp;E (MESH:D006371), Crystal violet (MESH:D005840), amino sugar (MESH:D000606), proflavine (MESH:D011370), PI (MESH:D011419), Mg2+ (-), hematoxylin (MESH:D006416), SYTO9 (MESH:C103389), K + (MESH:D011188)
- **Species:** Pseudomonas aeruginosa (species) [taxon 287], Klebsiella pneumoniae (species) [taxon 573], Streptococcus mutans (species) [taxon 1309], Bacillus subtilis (species) [taxon 1423], Salmonella (genus) [taxon 590], Escherichia coli (E. coli, species) [taxon 562], Acinetobacter baumannii (species) [taxon 470], Vibrio vulnificus (species) [taxon 672], Bacteria Latreille et al. 1825 (Bacteria stick insect, genus) [taxon 629395], Staphylococcus aureus (species) [taxon 1280], Rattus norvegicus (brown rat, species) [taxon 10116], Homo sapiens (human, species) [taxon 9606]
- **Mutations:** C for 5-7, C for 20-30, F200X
- **Cell lines:** ATCC 25923 — Homo sapiens (Human), Finite cell line (CVCL_LK64)

## Figures

7 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12965525/full.md

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Source: https://tomesphere.com/paper/PMC12965525