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High-Throughput Screening for Engineered Nanoparticles That Enhance Photosynthesis Using Mesophyll Protoplasts
journal contribution
posted on 2020-03-04, 21:47 authored by Aodi Wang, Qijie Jin, Xin Xu, Aijun Miao, Jason C. White, Jorge L. Gardea-Torresdey, Rong Ji, Lijuan ZhaoCertain engineered nanoparticles
(NPs) have unique properties that
have exhibited significant potential for promoting photosynthesis
and enhancing crop productivity. Understanding the fundamental interactions
between NPs and plants is crucial for the sustainable development
of nanoenabled agriculture. Leaf mesophyll protoplasts, which maintain
similar physiological response and cellular activity as intact plants,
were selected as a model system to study the impact of NPs on photosynthesis.
The mesophyll protoplasts isolated from spinach were cultivated with
different NMs (Fe, Mn3O4, SiO2, Ag,
and MoS2) dosing at 50 mg/L for 2 h under illumination.
The potential maximum quantum yield and adenosine triphosphate (ATP)
production of mesophyll protoplasts were significantly increased by
Mn3O4 and Fe NPs (23% and 43%, respectively),
and were decreased by Ag and MoS2 NPs. The mechanism for
the photosynthetic enhancement by Mn3O4 and
Fe is to increase the photocurrent and electron transfer rate, as
revealed by photoelectrochemical measurement. GC–MS based single
cell type metabolomics reveal that NPs (Fe and MoS2) altered
the metabolic profiles of mesophyll cells during 2 h of illumination
period. Separately, the effect of NPs exposure on photosynthesis and
biomass were also conducted at the whole plant level. A strong correlation
was observed with protoplast data; plant biomass was significantly
increased by Mn3O4 exposure (57%) but was decreased
(24%) by treatment of Ag NPs. The use of mesophyll protoplasts can
be a fast and reliable tool for screening NPs to enhance photosynthesis
for potential nanofertilizer use. Importantly, inclusion of a metabolic
analysis can provide mechanistic toxicity data to ensure the development
“safer-by-design” nanoenabled platforms.