Biosynthesis of selenium nanoparticles and effects of selenite, selenate, and selenomethionine on cell growth and morphology in Rahnella aquatilis HX2
| Autor: | Huafen Li, Yanbin Guo, Baoyu Ren, Guishen Zhao, Yanyun Zhu, Gary S. Bañuelos, Li Li, Zhi-Qing Lin |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
030106 microbiology chemistry.chemical_element Microbial Sensitivity Tests Selenic Acid Cell morphology Selenious Acid Applied Microbiology and Biotechnology Selenate Cell membrane 03 medical and health sciences chemistry.chemical_compound Selenium Biosynthesis medicine Selenomethionine Cell growth General Medicine Gene Expression Regulation Bacterial Anti-Bacterial Agents 030104 developmental biology medicine.anatomical_structure chemistry Biochemistry Cytoplasm Nanoparticles Rahnella aquatilis Rahnella Biotechnology |
| Zdroj: | Applied microbiology and biotechnology. 102(14) |
| ISSN: | 1432-0614 |
| Popis: | Rahnella aquatilis HX2 (proteobacteria) shows tolerance to selenium (Se). The minimum inhibitory concentrations of selenomethionine (Se-Met), selenite [Se (IV)], and selenate [Se (VI)] to HX2 are 4.0, 85.0, and 590.0 mM, respectively. HX2 shows the ability to reduce Se (IV) and Se (VI) to elemental Se nanoparticles (SeNPs). The maximum production of SeNPs by HX2 strain is 1.99 and 3.85 mM in Luria-Bertani (LB) broth with 5 mM Se (IV) and 10 mM Se (VI), respectively. The morphology of SeNPs and cells were observed by transmission electron microscope, environmental scanning electron microscope, and selected area electric diffraction detector. Spherical SeNPs with amorphous structure were found in the cytoplasm, membrane, and exterior of cells. Morphological variations of the cell membrane were further confirmed by the release of cellular materials absorbed at 260 nm. Flagella were inhibited and cell sizes were 1.8-, 1.6-, and 1.2-fold increases with the Se-Met, Se (VI), and Se (IV) treatments, respectively. The real-time quantitative PCR analysis indicated that some of the genes controlling Se metabolism or cell morphology, including cysA, cysP, rodA, ZntA, and ada, were significantly upregulated, while grxA, fliO, flgE, and fliC genes were significantly downregulated in those Se treatments. This study provided novel valuable information concerning the cell morphology along with biological synthesis process of SeNPs in R. aquatilis and demonstrated that the strain HX2 could be applied in both biosynthesis of SeNPs and in management of environmental Se pollution. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink