Molecular docking analysis of mosquito ribosomal protein in selenium nanoparticle bio-synthesis: Implications for pest and pathogen mitigation

Abstract

Background

Insects, rich in diverse proteins, are crucial in nanoparticle biofabrication. This study explores mosquito proteins' potential to reduce selenium ions and produce Selenium nanoparticles (SeNPs).

Methods

Mosquito larval protein composition was determined via liquid chromatography-mass spectrometry (LC-MS). Molecular docking validated cytoskeletal proteins' efficacy, notably 40S ribosomal protein S7 (binding energy: -6.23) and β-tubulin (binding energy: -5.94), in facilitating selenium ion conversion to SeNPs. SeNPs, mediated by these proteins, were characterized using Ultra Violet-visible spectroscopy, revealing a peak at 295 nm. FT-IR analysis identified biomolecules responsible for capping SeNPs and converting selenious acid to SeNPs.

Significant findings

LC-MS detected β-tubulin (1 peptide, 76 amino acids, 8.2 kDa) and 40S ribosomal protein S7 (2 peptides, 192 amino acids, 22.1 kDa). The FT-IR analysis showed peaks at 3420.89 (OH stretch), 2928.35 (aromatic CH stretch), 2344.02 (CC alkynes stretches), etc. X-Ray Diffraction confirmed SeNPs' crystalline structure. Scanning electron microscopy and transmission electron microscopy revealed smooth-surfaced SeNPs in spherical and rod-shaped forms. SDS PAGE analysis post-SeNPs synthesis confirmed 40S ribosomal protein S7 and β-tubulin presence. SeNPs exhibited antibacterial, anti-biofilm, antioxidant, photocatalytic, and insecticidal activities. Median lethal concentrations were 17.674 μg/mL for Culex quinquefasciatus, 31.117 μg/mL for Aedes aegypti, and 81.95 μg/mLfor R. dominica at 48 h. SeNPs suppressed S. aureus biofilm by 33.06 ± 8.26 % and E. coli by 13.8 ± 3.63 %. Vero cells showed no harm at 250 µg/mL SeNPs. At 100 μg/mL, SeNPs exhibited 52.94 % free radical scavenging, compared to 74 % for ascorbic acid. Protein-mediated nanoparticle preparation is favoured for biomedical applications due to ease of synthesis, eco-friendliness, conjugation capability, simple preparation, and utilization of pests.