Anti-Biofilm Activity of Graphene Quantum Dots via Self-Assembly with Bacterial Amyloid Proteins

Abstract

Bacterial biofilms represent an essential part of Earth's ecosystem that can cause multiple ecological, technological and health problems. The environmental resilience and sophisticated organization of biofilms are enabled by the extracellular matrix that creates a protective network of biomolecules around the bacterial community. Current anti-biofilm agents can interfere with extracellular matrix production but, being based on small molecules, are degraded by bacteria and rapidly diffuse away from biofilms. Both factors severely reduce their efficacy, while their toxicity to higher organisms create additional barriers to their practicality. In this paper we report on the ability of graphene quantum dots to effectively disperse mature amyloid-rich Staphylococcus aureus biofilms, interfering with the self-assembly of amyloid fibers-a key structural component of the extracellular matrix. Mimicking peptide-binding biomolecules, graphene quantum dots form supramolecular complexes with phenol soluble modulins, the peptide monomers of amyloid fibers.

Nanosilver Mitigates Biofilm Formation via FapC Amyloidosis Inhibition

“…Amyloidosis inhibition with nanomaterials is an emerging frontier against amyloid diseases, but has rarely been attempted before for antimicrobial purposes . Here, the effects of bPEI‐capped AgNPs or AgNCs on FapC fibrillization were systematically investigated to inhibit biofilm formation by P. aeruginosa .…”

Graphene Quantum Dots as Flourishing Nanomaterials for Bio-Imaging, Therapy Development, and Micro-Supercapacitors

“…Amyloidosis is a well-known aggregation and deposition of amyloid proteins as cross-beta sheets or fibrils in plaques around cells leading to organ and tissue failures. This phenomenon is responsible for a great number of degenerative disorders such as Alzheimer’s disease, Parkinson´s disease, type 2 diabetes, as well as for providing stability to bacterial biofilms [ 168 , 169 , 170 , 171 , 172 , 173 ]. Therefore, various candidates for the inhibition of amyloid aggregation, such as small molecules and peptides, have been studied over the years [ 174 , 175 ].…”

“…Therefore, various candidates for the inhibition of amyloid aggregation, such as small molecules and peptides, have been studied over the years [ 174 , 175 ]. Protein accumulation inhibitors generally try to substitute the hydrogen bonding, hydrophobic interaction, and π–π -stacking of the amyloid protein to disassemble their aggregation [ 173 ]. GQDs have been reported as outstanding inhibitors of aggregation, toxicity of pathogenic and functional amyloid species due to their functionalized surface, which improves their antiamyloid targeting and delivery [ 175 ].…”

Specific Antibiofilm of Carbon Quantum Dots by Destroying P. gingivalis Biofilm Related Proteins Self-assembly

“…While Tinidazole does not displayed drastically effect on the biofilm. Therefore, the nanostructures of TCDs may play an important role in penetrating the biofilms by affecting P. gingivalis producing Fibrin, the important components of mature biofilms [16].…”

“…However, it's effect is very limited because most antibiotics used in clinical context can only maintain high efficiency over a short time, and resistant strains will soon occur due to continuous use of antibiotics. The main reason for this dilemma is that the biofilm produced from the bacteria, a membrane-like structure composed of microbial cells and extracellular polymer complexes surrounded by exopolysaccharides on biotic or abiotic surfaces [14][15][16], which protected bacteria under the biofilm from antibacterial agents and host defense mechanisms and subsequently makes the drug failure [17], also in turn triggers bacterial resistance [18][19][20]. In addition, although antibiotics can inhibit the symptoms of present infection by killing exfoliated zooplankton in vivo, but antibiotic cannot eradicate bacteria located in the deep embedded biofilm [21].…”