Investigation into the Antibacterial Mechanism of Biogenic Tellurium Nanoparticles and Precursor Tellurite

Abstract

Antibacterial tellurium nanoparticles have the advantages of high activity and biocompatibility. Microbial synthesis of Te nanoparticles is not only a green technology but builds new ecological relationships in diverse environments. However, the antibacterial mechanism of Te nanoparticles is largely unclear. In this study, we report the bacterial synthesis of rod-shaped Te nanoparticles (BioTe) with high antibacterial activity against Escherichia coli. Morphology and permeability examination indicates that membrane damage is the primary reason for the antibacterial activity of BioTe, rather than ROS production and DNA damage. Moreover, a comparison of transcriptome and relative phenotypes reveals the difference in antibacterial mechanisms between BioTe and tellurite. Based on our evidence, we propose an antibacterial mode of rod-shaped BioTe, in which positively charged BioTe interact with the cell membrane through electrostatic attraction and then penetrate the membrane by using their sharp ends. In contrast, tellurite toxicity might be involved in sulfur metabolism.

Biosynthesis of Novel Tellurium Nanorods by Gayadomonas sp. TNPM15 Isolated from Mangrove Sediments and Assessment of Their Impact on Spore Germination and Ultrastructure of Phytopathogenic Fungi

“…The biosynthesis of tellurium nanorods by Gayadomonas sp. TNPM15 supports the findings of previous works that demonstrated the biosynthesis of rod-shaped TeNPs by various microorganisms [ 2 , 81 , 82 , 83 ]. Our findings agree with most previous literature reporting the intracellular biosynthesis of TeNPs [ 25 , 26 , 75 , 84 ].…”

“…This disintegration of the membrane was affirmed by increasing in the leakage of DNA and proteins. These findings concord with previous reports, suggesting that the antimicrobial effect of various nanoparticles may be attributed to the disintegration of membranes and leakage of the intracellular content, as well as the rupture of cell walls [ 2 , 86 , 87 , 88 , 89 , 90 , 91 ]. Interestingly, the biogenic TeNPs produced by Gayadomonas sp.…”

“…Undoubtedly, nanoparticles have extraordinary advantages compared to bulk materials due to their larger surface-to-volume ratios and higher spatial confinement [ 1 ]. In this trend, extensive attempts have been employed to fabricate metal, metal oxide and metalloid nanoparticles as alternative antimicrobial agents, such as silver, gold, copper, zinc, selenium, and tellurium nanoparticles [ 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ]. Recently, tellurium nanoparticles (TeNPs) have drawn significant attention due to their antibacterial and antifungal activity, besides biocompatibility [ 12 ].…”

Antibacterial activity and mechanism of sanguinarine against Staphylococcus aureus by interfering with the permeability of the cell wall and membrane and inducing bacterial ROS production

“…As an important signaling molecule, ROS can reflect the cellular activity state. Although cells can continuously produce low levels of ROS to maintain a normal cellular life activity, when the amount of intracellular ROS exceeds the capacity of the antioxidant mechanism, excessive oxidative stress will lead to irreversible damage to intracellular macromolecules ( 31 ). Tang et al ( 31 ) explored the in vitro antibacterial mechanism of biogenic tellurium nanoparticles and precursor tellurite against Escherichia coli , and the measurement of ROS levels were found to be significantly higher in the experimental group.…”

“…ROS Measurement was performed according to Tang et al ( 31 ). In brief, DCFH-DA (Beyotime Biotechnology, S0033S, Shanghai, China) was incubated with the bacteria for 20 min at 37°C and washed with PBS 3 times.…”