Influence of Bacterial Physiology on Processing of Selenite, Biogenesis of Nanomaterials and Their Thermodynamic Stability

Molecules

Marta Bardelli¹  Giovanni Vallini¹  Alessandro Presentato¹  Silvia Lampis¹  Elena Piacenza²  RaymondJ. Turner² 

[1] Environmental Microbiology and Microbial Biotechnology Laboratory, Department of Biotechnology, University of Verona, 37134 Verona, Italy;Microbial Biochemistry Laboratory, Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada;

关键词: biogenic nanomaterials;    selenium nanomaterials;    selenite;    selenium nanoparticles;    selenium nanorods;    Ochrobactrum;    thermodynamic stability;    electrosteric stabilization;   

DOI  :  10.3390/molecules24142532

来源: DOAJ

【 摘 要 】

We explored how Ochrobactrum sp. MPV1 can convert up to 2.5 mM selenite within 120 h, surviving the challenge posed by high oxyanion concentrations. The data show that thiol-based biotic chemical reaction(s) occur upon bacterial exposure to low selenite concentrations, whereas enzymatic systems account for oxyanion removal when 2 mM oxyanion is exceeded. The selenite bioprocessing produces selenium nanomaterials, whose size and morphology depend on the bacterial physiology. Selenium nanoparticles were always produced by MPV1 cells, featuring an average diameter ranging between 90 and 140 nm, which we conclude constitutes the thermodynamic stability range for these nanostructures. Alternatively, selenium nanorods were observed for bacterial cells exposed to high selenite concentration or under controlled metabolism. Biogenic nanomaterials were enclosed by an organic material in part composed of amphiphilic biomolecules, which could form nanosized structures independently. Bacterial physiology influences the surface charge characterizing the organic material, suggesting its diverse biomolecular composition and its involvement in the tuning of the nanomaterial morphology. Finally, the organic material is in thermodynamic equilibrium with nanomaterials and responsible for their electrosteric stabilization, as changes in the temperature slightly influence the stability of biogenic compared to chemogenic nanomaterials.

【 授权许可】

Unknown