Highly Selenite-Tolerant Strain Proteus mirabilis QZB-2 Rapidly Reduces Selenite to Selenium Nanoparticles in the Cell Membrane.

ABSTRACT: The application of biosynthesized nano-selenium fertilizers to crops can improve their nutrient levels by increasing their selenium content. However, microorganisms with a high selenite tolerance and rapid reduction rate accompanied with the production of selenium nanoparticles (SeNPs) at the same time have seldom been reported. In this study, a bacterial strain showing high selenite resistance (up to 300 mM) was isolated from a lateritic red soil and identified as Proteus mirabilis QZB-2. This strain reduced nearly 100% of 1.0 and 2.0 mM selenite within 12 and 18 h, respectively, to produce SeNPs. QZB-2 isolate reduced SeO₃ ^{2 -} to Se⁰ in the cell membrane with NADPH or NADH as electron donors. Se⁰ was then released outside of the cell, where it formed spherical SeNPs with an average hydrodynamic diameter of 152.0 ± 10.2 nm. P. mirabilis QZB-2 could be used for SeNPs synthesis owing to its simultaneously high SeO₃ ^{2 -} tolerance and rapid reduction rate.

SUBMITTER: Huang J 

PROVIDER: S-EPMC9037631 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature