Biosynthesis of selenium-nanoparticles and -nanorods as a product of selenite bioconversion by the aerobic bacterium Rhodococcus aetherivorans BCP1

6533b7d8fe1ef96bd126a404

RESEARCH PRODUCT

Biosynthesis of selenium-nanoparticles and -nanorods as a product of selenite bioconversion by the aerobic bacterium Rhodococcus aetherivorans BCP1

Elena Piacenza Alessandro Presentato Davide Zannoni Martina Cappelletti Max Anikovskiy Raymond J. Turner

subject

0301 basic medicine Bioconversion Static Electricity 030106 microbiology chemistry.chemical_element Bioengineering Selenious Acid Settore BIO/19 - Microbiologia Generale Selenium pollution Selenium 03 medical and health sciences Minimum inhibitory concentration chemistry.chemical_compound Nanoparticle Biosynthesis Rhodococcus Particle Size Selenite Rhodococcus aetherivorans Selenium nanoparticles Selenium nanorods Biogenic nanostructures Selenium nanorod Molecular Biology Nanotubes biology Biogenic nanostructure Rhodococcus aetherivoran Spectrometry X-Ray Emission General Medicine biology.organism_classification Dynamic Light Scattering Selenium nanoparticle Bacteria Aerobic Nanotube 030104 developmental biology chemistry Biochemistry 13. Climate action Selenious Acid Selenite Nanoparticles Metalloid Rhodococcus Selenium Rhodococcu Biotechnology

description

The wide anthropogenic use of selenium compounds represents the major source of selenium pollution world- wide, causing environmental issues and health concerns. Microbe-based strategies for metal removal/recovery have received increasing interest thanks to the association of the microbial ability to detoxify toxic metal/ metalloid polluted environments with the production of nanomaterials. This study investigates the tolerance and the bioconversion of selenite (SeO32−) by the aerobically grown Actinomycete Rhodococcus aetherivorans BCP1 in association with its ability to produce selenium nanoparticles and nanorods (SeNPs and SeNRs). The BCP1 strain showed high tolerance towards SeO32− with a Minimal Inhibitory Concentration (MIC) of 500 mM. The bio- conversion of SeO32− was evaluated considering two different physiological states of the BCP1 strain, i.e. un- conditioned and/or conditioned cells, which correspond to cells exposed for the first time or after re-inoculation in fresh medium to either 0.5 or 2 mM of Na2SeO3, respectively. SeO32− bioconversion was higher for conditioned grown cells compared to the unconditioned ones. Selenium nanostructures appeared polydisperse and not ag- gregated, as detected by electron microscopy, being embedded in an organic coating likely responsible for their stability, as suggested by the physical-chemical characterization. The production of smaller and/or larger SeNPs was influenced by the initial concentration of provided precursor, which resulted in the growth of longer and/or shorter SeNRs, respectively. The strong ability to tolerate high SeO32− concentrations coupled with SeNP and SeNR biosynthesis highlights promising new applications of Rhodococcus aetherivorans BCP1 as cell factory to produce stable Se-nanostructures, whose suitability might be exploited for biotechnology purposes.

year	journal	country	edition	language
2018-01-01	New Biotechnology

https://doi.org/10.1016/j.nbt.2017.11.002