Biofabrication of nanomaterials is currently constrained by a low production efficiency and poor controllability on product quality compared to chemical synthetic routes. In this work, we show an ...attractive new biosynthesis system to break these limitations. A directed production of selenium-containing nanoparticles in Shewanella oneidensis MR-1 cells, with fine-tuned composition and subcellular synthetic location, was achieved by modifying the extracellular electron transfer chain. By taking advantage of its untapped intracellular detoxification and synthetic power, we obtained high-purity, uniform-sized cadmium selenide nanoparticles in the cytoplasm, with the production rates and fluorescent intensities far exceeding the state-of-the-art biosystems. These findings may fundamentally change our perception of nanomaterial biosynthesis process and lead to the development of fine-controllable nanoparticles biosynthesis technologies.
Constructing artificial interface layer is an effective approach to facilitate the utilization rate of zinc metal, but the practical application is still hindered by the inferior mechanical strength, ...low ionic conductivity, and poor stability. Herein, robust organic–inorganic layer (Nafion/BM@Zn) is coated on zinc metal through ultrasonic spraying method with boehmite and Nafion as the composite precursor. As demonstrated, the high cation selectivity and high hydrophilicity of Nafion, as well as the zincophilic property and layered structure of boehmite, synergistically contribute to the low nucleation barrier, uniform deposition, and fast transport kinetics of Zn2+ ions. As a result, the Nafion/BM@Zn anode exhibits superior reversibility with a high Coulombic efficiency of 99.9% for 9000 cycles in asymmetrical cells and durable cycling stability for 4200 h in symmetrical cells at 5 mA cm−2−1 mAh cm−2. Even in the seawater‐based electrolyte, the Nafion/BM@Zn anode still displays reversible deposition behavior for 820 h and high Coulombic efficiency of 99.91% for 2800 cycles at 5 mA cm−2−1 mAh cm−2. Furthermore, the corresponding Nafion/BM@Zn//NH4V4O10 cell presents high capacity of 258.4 mAh g−1 after 1500 cycles at 5 A g−1. This work provides a new design strategy for high‐efficiency interfacial layer of zinc metal anode.
Robust organic–inorganic hybrid layer of Nafion and boehmite composite is constructed on the surface of zinc metal through ultrasonic spraying method to address the issues of dendrite growth and side reactions. Consequently, high cation selectivity of Nafion, and high zincophilic property of boehmite, contribute to the low nucleation barrier, uniform deposition, and fast transport kinetics of Zn2+ ions.
Quantum dots (QDs) are recognized as the excellent fluorescence and photochemical materials to be applied in bioimaging, biomedical, and solar cell fields. Biosynthesized QDs (bio-QDs) have attracted ...attention due to their simple, eco-friendly, and excellent biocompatible traits. Moreover, bio-QDs could not be replaced by chemically fabricated QDs in many fields. Bio-QDs synthesized by different microorganisms have diverse characteristics. In this work, the biosynthesis of QDs by
Tetrahymena pyriformis
, a typical protozoa in aquatic environments, was achieved for the first time. The synthesized materials by
T. pyriformis
emitted yellow fluorescence and had an average diameter of 8.27 ± 0.77 nm. Spectral characterization results demonstrated that the synthesized QDs were CdS
1-X
Se
X
. Meanwhile, the fluorescence intensities of the synthesized bio-QDs showed a linear relationship with Cd
2+
dosage ranging from 20 to 80 μM. The fluorescence enhancement of the synthesized QDs was highly selective to Cd
2+
compared to other metal ions. The bio-QDs were demonstrated to have a great potential to be applied for Cd
2+
detection. This work provides valuable information about the transformation of heavy metal ions in protozoan and is useful to accelerate the applications of the synthesized QDs.
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Nano-selenium has a great potential to be used in chemical, biological, medical and environmental fields. Biological methods for nano-selenium synthesis have attracted wide interests, ...because they can be operated at ambient temperature and pressure without complicated equipments. In this work, a protozoa, Tetrahymena thermophila (T. thermophila) SB210, was used to in vivo synthesize nano-selenium. The biosynthesized nano-selenium was characterized using transmission electron microscopy, energy dispersive X-ray spectroscopy and Raman spectroscopy. The synthesized amorphous spherical selenium nanoparticles had diameters of 50–500nm with the coexistence of irregular nano-selenium. The expressions of glutathione (GSH) synthesis related gene glutathione synthase, cysteine-rich protein metallothionein related gene metallothionein-1 and 2Fe-2S cluster-binding protein related gene were up-regulated in the nano-selenium producing group. Also, the subsequent GSH detection and in vitro synthesis experimental results suggest the three proteins were likely to be involved in the nano-selenium synthesis process.
Ciprofloxacin (CIP), as an extensively used antibiotic, has been widely detected at a high level in the environment and has raised environmental pollution concerns. Thus, efficient and cost-effective ...methods for CIP degradation are highly desired. Biologically produced manganese oxides (BioMnOx) offer a promising perspective for CIP degradation because of their catalytic reactivity and cost-effectiveness. However, the release of Mn(II) from BioMnOx prevents the further oxidation of pollutants. As a consequence, continuous CIP degradation by BioMnOx is not feasible. In this work, a manganese redox cycling system driven by Pseudomonas putida MnB-1 was constructed for continuous degradation of CIP. In such a system CIP was oxidized continuously and rapidly by re-oxidizing the formed Mn(II) to regenerate reactive BioMnOx, which also protected the strain from CIP toxicity. CIP was degraded through N-dealkylation passway. No significant loss of BioMnOx reactivity was observed in three-cycle CIP degradation process, suggesting the stability of this system. An overlooked intracellular BioMnOx, which was involved in CIP degradation, was discovered in P. putida MnB-1. Moreover, the important role of Mn(III) in facilitating CIP removal in this system was also identified. This work provides useful information to better understand the degradation of antibiotic compounds mediated by microbes in environments.
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•A Mn-cycling biosystem was constructed for continuous degradation of CIP.•No loss of BioMnOx reactivity was observed in cycling CIP degradation process.•An overlooked intracellular BioMnOx involving in CIP degradation was found.•This system can be widely used for the biodegradation of other pollutants.
Photothermal therapy (PTT) is a minimally invasive and effective cancer treatment method and has a great potential for innovating the conventional chemotherapy approaches. Copper sulfide (CuS) ...exhibits photostability, low cost, and high absorption in near infrared region, and is recognized as an ideal candidate for PTT. However, CuS, as a photothermal agent, is usually synthesized with traditional chemical approaches, which require high temperature, additional stabilization and hydrophilic modification. Herein, we report, for the first time, the preparation of CuS nanoparticles as a photothermal agent by a dissimilatory metal reducing bacterium Shewanella. oneidensis MR-1. The prepared nanoparticles are homogenously shaped, hydrophilic, small-sized (∼5nm) and highly stable. Furthermore, the biosynthesized CuS nanoparticles display a high photothermal conversion efficiency of 27.2% because of their strong absorption at 1100nm. The CuS nanoparticles could be effectively used as a PTT agent under the irradiation of 1064nm. This work provides a simple, eco-friendly and cost-effective approach for fabricating PTT agents.
Various apolipoproteins widely distributed among vertebrata play key roles in lipid metabolism and have a direct correlation with human diseases as diagnostic markers. However, the evolutionary ...progress of apolipoproteins in species remains unclear. Nine human apolipoproteins and well-annotated genome data of 30 species were used to identify 210 apolipoprotein family members distributed among species from fish to humans. Our study focused on the evolution of nine exchangeable apolipoproteins (ApoA-I/II/IV/V, ApoC-I~IV and ApoE) from Chondrichthyes, Holostei, Teleostei, Amphibia, Sauria (including Aves), Prototheria, Marsupialia and Eutheria.
In this study, we reported the overall distribution and the frequent gain and loss evolutionary events of apolipoprotein family members in vertebrata. Phylogenetic trees of orthologous apolipoproteins indicated evident divergence between species evolution and apolipoprotein phylogeny. Successive gain and loss events were found by evaluating the presence and absence of apolipoproteins in the context of species evolution. For example, only ApoA-I and ApoA-IV occurred in cartilaginous fish as ancient apolipoproteins. ApoA-II, ApoE, and ApoC-I/ApoC-II were found in Holostei, Coelacanthiformes, and Teleostei, respectively, but the latter three apolipoproteins were absent from Aves. ApoC-I was also absent from Cetartiodactyla. The apolipoprotein ApoC-III emerged in terrestrial animals, and ApoC-IV first arose in Eutheria. The results indicate that the order of the emergence of apolipoproteins is most likely ApoA-I/ApoA-IV, ApoE, ApoA-II, ApoC-I/ApoC-II, ApoA-V, ApoC-III, and ApoC-IV.
This study reveals not only the phylogeny of apolipoprotein family members in species from Chondrichthyes to Eutheria but also the occurrence and origin of new apolipoproteins. The broad perspective of gain and loss events and the evolutionary scenario of apolipoproteins across vertebrata provide a significant reference for the research of apolipoprotein function and related diseases.
Organisms served as factories of bio-assembly of nanoparticles attracted a lot of attentions due to the safe, economic and environmental-benignity traits, especially the fabrication of the super ...fluorescence properties quantum dots (QDs). However, information about the developmental dynamics of QDs in living organisms is still lacking. In this work, we synthesized cadmium-selenium (CdSe) QDs in Candida utilis WSH02-08, and then tracked and quantitatively characterized the developmental dynamics (photoactivation, photostable and photobleaching processes) of bio-QDs by translating fluorescence microscopy movies into visual quantitative curve. These findings shed light on the fluorescence properties of the bio-assembled QDs and are expected to accelerate the applications of the synthesized QDs in vivo. It provided a new way to screen bio-QDs and monitor the quality of QDs in vivo.
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•High-quality CdSe QDs were synthesized in Candida utilis.•QDs fluorescence properties were tuned via adjusting precursor concentrations.•The synthesized QDs were directly used for ...bio-imaging.
Quantum dots (QDs), owning to their unique optical and electronic properties, are increasingly used for bio-imaging/biosensing in medical and energy fields. Biosynthesis of QDs offers several advantages over the conventional chemical synthesis route, such as low cost, environmental-benignity, and no need for further modification of the products. However, information about the regulation and mechanism of synthesis of QDs with great fluorescence properties is still limited. In this work, we prepared cadmium-selenium (CdSe) QDs in vivo using Candida utilis WSH02-08. We regulated the fluorescence properties of the bio-QDs through different precursor concentrations, and found that the bio-QDs with high fluorescence intensity and long photostable lifetime were favoured at an elevated Cd content over Se. The synthesis of the high-quality bio-QDs was attributed to the less formation of Se(0) and the increased formation of CdSe and CdS. Furthermore, such synthesized QDs were directly used in live-cell imaging without further modification. These findings are expected to enable a further design of biosynthesized QDs with great fluorescence properties and expand our understanding of the regulation mechanism of nanoparticles fabrication in microorganisms.
Planarians exhibit an extraordinary ability to regenerate lost body parts which is attributed to an abundance of pluripotent somatic stem cells called neoblasts. In this article, we report a ...transcriptome sequence of a Planaria subspecies
Dugesia japonica derived by high-throughput sequencing. In addition, we researched transcriptome changes during different periods of regeneration by using a tag-based digital gene expression (DGE) system. Consequently, 11,913,548 transcriptome sequencing reads were obtained. Finally, these reads were eventually assembled into 37,218 unique unigenes. These assembled unigenes were annotated with various methods. Transcriptome changes during planarian regeneration were investigated by using a tag-based DGE system. We obtained a sequencing depth of more than 3.5
million tags per sample and identified a large number of differentially expressed genes at various stages of regeneration. The results provide a fairly comprehensive molecular biology background to the research on planarian development, particularly with regard to its regeneration progress.
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