Articles
BioNanoScience (21911630)15(3)
Streptococci and Staphylococci are pathogenic agents that cause antibiotic-resistant infections through biofilm formation. Therefore, researchers are seeking alternative methods to combat antibiotic-resistant infections. This study aimed to compare the anti-biofilm effect of an aptamer-silver nanoparticle complex (Apt-AgNP) on Streptococci and Staphylococci. In the in silico studies, the physicochemical properties and secondary and tertiary structures of the selected bacterial surface proteins were compared and validated using ProtParam, GOR IV, SWISS-MODEL, Phyre2, I-TASSER, and GalaxyWEB servers. Aptamer binding to proteins was performed using molecular docking with HDock and ZDock servers. In the in vitro experiments, silver nanoparticles were synthesized and then attached to biotinylated AptBH via streptavidin. The anti-biofilm effect of Apt-AgNP on Streptococci and Staphylococci was compared with that of silver nanoparticles alone. For the characterization of silver nanoparticles and Apt-AgNP, XRD, FESEM, DLS, and zeta potential tests were used. The in silico results showed that aptamer docking with staphylococcal surface proteins yielded high binding scores, with the best results of − 310.74 for S. aureus and − 300.76 for S. epidermidis on the HDock server. Characterization results confirmed the spherical shape of the silver nanoparticles with a size of approximately 80 nm and their successful attachment to the aptamer. The Apt-AgNP at a concentration of 400 μg/mL showed a better anti-biofilm effect compared to silver nanoparticles alone. The highest anti-biofilm effect of this complex was observed on Staphylococci (69–72%). Overall, the consistency between in silico and in vitro results demonstrated the potential of this complex in developing new strategies for combating bacterial infections. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.
International Journal of Biological Macromolecules (01418130)296
Fire blight, caused by Erwinia amylovora, is a significant threat to fruit crops, with limited biocontrol methods. This study aimed to develop a nanosystem using mesoporous silica nanoparticles (MSNs) loaded with a phenolic plant extract (ZP) derived from Myrtus communis, Thymus vulgaris, and Curcuma longa, and coated with natural biopolymers Gum Tragacanth (GT) and sodium alginate (SA). The MSNs were synthesized and characterized by XRD, FTIR, and TEM, exhibiting a specific surface area of about 750 m2/g and an average pore diameter of 5 nm. ZP was effectively loaded into the MSNs with a loading efficiency of ∼25 %, and GT-MSNs-ZP demonstrated sustained release, releasing 56 % of phenolic compounds over 168 h. In antibacterial tests, GT-MSNs-ZP demonstrated the highest effectiveness against E. amylovora, maintaining inhibition for up to 7 days. In vivo experiments showed that GT-MSNs-ZP reduced diseased leaves by 60 % at a concentration of 5/1000 mL/mL, comparable to commercial pesticides. Additionally, the system showed no adverse effects on beneficial bacteria such as Rhizobium meliloti and Bacillus licheniformis. These results emphasize the potential of GT-MSNs-ZP as a sustainable and effective biocontrol solution for agricultural applications. © 2025 Elsevier B.V.
Molecular Biology Research Communications (2322181X)14(1)pp. 1-14
Pseudomonas syringae is a gram-negative bacterium that causes a diversity of diseases in numerous plants. Strategies to inhibit P. syringae growth include protective procedures; however, controlling the disease is complicated due to its rapid spread. Several antimicrobial agents can prevent this disease, such as chemical compounds, biological agents, secondary metabolites, nanoparticles, bacteriophages, and antimicrobial peptides (AMPs). The most effective way to control the disease is through chemical control. Using copper compounds and antibiotics is a conventional practice to decrease canker disease symptoms. However, due to environmental pollution caused by chemicals and bactericides and the resistance of different pathovars of P. syringae, other methods for bacterial pathogens control are needed. Biological control, using antagonistic bacteria has shown promising results against P. syringae under in vitro conditions. New studies focus on using secondary metabolites from plants to control plant diseases. Studies have shown that essential oils when preserved from degradation and evaporation by nanoparticles like mesoporous silica, can increase their antibacterial activities. Using nanoparticles, especially silver, is a suitable strategy for controlling P. syringae. However, high concentrations of silver nanoparticles are toxic. Bacteriophages and AMPs are recommended as alternatives to control bacterial infections in agriculture, including P. syringae. Combined treatments of phages and secondary metabolites have shown higher efficacy, potentially overcoming resistance. However, bacteriophages and AMPs are expensive and limited. In the end, using secondary metabolites and nanoparticles at low concentrations presents economic benefits and antibacterial activities without phytotoxic properties. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/).
