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1.
Anal Chem ; 96(23): 9684-9692, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38804540

RESUMO

Herein, we report a DNA origami plasmonic nanoantenna for the programmable surface-enhanced Raman scattering (SERS) detection of cytokine release syndrome (CRS)-associated cytokines (e.g., tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)) in cancer immunotherapy. Typically, the nanoantenna was made of self-assembled DNA origami nanotubes (diameter: ∼19 nm; length: ∼90 nm) attached to a silver nanoparticle-modified silicon wafer (AgNP/Si). Each DNA origami nanotube contains one miniature gold nanorod (AuNR) inside (e.g., length: ∼35 nm; width: ∼7 nm). Intriguingly, TNF-α and IFN-γ logically regulate the opening of the nanotubes and the dissociation of the AuNRs from the origami structure upon binding to their corresponding aptamers. On this basis, we constructed a complete set of Boolean logic gates that read cytokine molecules as inputs and return changes in Raman signals as outputs. Significantly, we demonstrated that the presented system enables the quantification of TNF-α and IFN-γ in the serum of tumor-bearing mice receiving different types of immunotherapies (e.g., PD1/PD-L1 complex inhibitors and STING agonists). The sensing results are consistent with those of the ELISA. This strategy fills a gap in the use of DNA origami for the detection of multiple cytokines in real systems.


Assuntos
Técnicas Biossensoriais , Citocinas , DNA , Ouro , Imunoterapia , Nanopartículas Metálicas , Análise Espectral Raman , Animais , Camundongos , DNA/química , Citocinas/metabolismo , Citocinas/sangue , Ouro/química , Nanopartículas Metálicas/química , Humanos , Prata/química , Nanotubos/química , Neoplasias , Interferon gama/sangue , Interferon gama/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/sangue
2.
Small ; : e2402101, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888117

RESUMO

Tumor-associated macrophages (TAMs) play a crucial function in solid tumor antigen clearance and immune suppression. Notably, 2D transitional metal dichalcogenides (i.e., molybdenum disulfide (MoS2) nanozymes) with enzyme-like activity are demonstrated in animal models for cancer immunotherapy. However, in situ engineering of TAMs polarization through sufficient accumulation of free radical reactive oxygen species for immunotherapy in clinical samples remains a significant challenge. In this study, defect-rich metastable MoS2 nanozymes, i.e., 1T2H-MoS2, are designed via reduction and phase transformation in molten sodium as a guided treatment for human breast cancer. The as-prepared 1T2H-MoS2 exhibited enhanced peroxidase-like activity (≈12-fold enhancement) than that of commercial MoS2, which is attributed to the charge redistribution and electronic state induced by the abundance of S vacancies. The 1T2H-MoS2 nanozyme can function as an extracellular hydroxyl radical generator, efficiently repolarizing TAMs into the M1-like phenotype and directly killing cancer cells. Moreover, the clinical feasibility of 1T2H-MoS2 is demonstrated via ex vivo therapeutic responses in human breast cancer samples. The apoptosis rate of cancer cells is 3.4 times greater than that of cells treated with chemotherapeutic drugs (i.e., doxorubicin).

3.
Nature ; 559(7714): 370-376, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29973727

RESUMO

From bacteria following simple chemical gradients1 to the brain distinguishing complex odour information2, the ability to recognize molecular patterns is essential for biological organisms. This type of information-processing function has been implemented using DNA-based neural networks3, but has been limited to the recognition of a set of no more than four patterns, each composed of four distinct DNA molecules. Winner-take-all computation4 has been suggested5,6 as a potential strategy for enhancing the capability of DNA-based neural networks. Compared to the linear-threshold circuits7 and Hopfield networks8 used previously3, winner-take-all circuits are computationally more powerful4, allow simpler molecular implementation and are not constrained by the number of patterns and their complexity, so both a large number of simple patterns and a small number of complex patterns can be recognized. Here we report a systematic implementation of winner-take-all neural networks based on DNA-strand-displacement9,10 reactions. We use a previously developed seesaw DNA gate motif3,11,12, extended to include a simple and robust component that facilitates the cooperative hybridization13 that is involved in the process of selecting a 'winner'. We show that with this extended seesaw motif DNA-based neural networks can classify patterns into up to nine categories. Each of these patterns consists of 20 distinct DNA molecules chosen from the set of 100 that represents the 100 bits in 10 × 10 patterns, with the 20 DNA molecules selected tracing one of the handwritten digits '1' to '9'. The network successfully classified test patterns with up to 30 of the 100 bits flipped relative to the digit patterns 'remembered' during training, suggesting that molecular circuits can robustly accomplish the sophisticated task of classifying highly complex and noisy information on the basis of similarity to a memory.


Assuntos
DNA/química , Modelos Neurológicos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Memória , Neurônios/fisiologia
4.
Nature ; 552(7683): 67-71, 2017 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-29219965

RESUMO

Self-assembled DNA nanostructures enable nanometre-precise patterning that can be used to create programmable molecular machines and arrays of functional materials. DNA origami is particularly versatile in this context because each DNA strand in the origami nanostructure occupies a unique position and can serve as a uniquely addressable pixel. However, the scale of such structures has been limited to about 0.05 square micrometres, hindering applications that demand a larger layout and integration with more conventional patterning methods. Hierarchical multistage assembly of simple sets of tiles can in principle overcome this limitation, but so far has not been sufficiently robust to enable successful implementation of larger structures using DNA origami tiles. Here we show that by using simple local assembly rules that are modified and applied recursively throughout a hierarchical, multistage assembly process, a small and constant set of unique DNA strands can be used to create DNA origami arrays of increasing size and with arbitrary patterns. We illustrate this method, which we term 'fractal assembly', by producing DNA origami arrays with sizes of up to 0.5 square micrometres and with up to 8,704 pixels, allowing us to render images such as the Mona Lisa and a rooster. We find that self-assembly of the tiles into arrays is unaffected by changes in surface patterns on the tiles, and that the yield of the fractal assembly process corresponds to about 0.95m - 1 for arrays containing m tiles. When used in conjunction with a software tool that we developed that converts an arbitrary pattern into DNA sequences and experimental protocols, our assembly method is readily accessible and will facilitate the construction of sophisticated materials and devices with sizes similar to that of a bacterium using DNA nanostructures.


Assuntos
DNA/química , DNA/síntese química , Fractais , Nanoestruturas/química , Nanotecnologia , Conformação de Ácido Nucleico , Animais , Automação , Sequência de Bases , Galinhas , Masculino , Pinturas , Software
5.
Sensors (Basel) ; 23(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37112311

RESUMO

Multi-scale feature fusion techniques and covariance pooling have been shown to have positive implications for completing computer vision tasks, including fine-grained image classification. However, existing algorithms that use multi-scale feature fusion techniques for fine-grained classification tend to consider only the first-order information of the features, failing to capture more discriminative features. Likewise, existing fine-grained classification algorithms using covariance pooling tend to focus only on the correlation between feature channels without considering how to better capture the global and local features of the image. Therefore, this paper proposes a multi-scale covariance pooling network (MSCPN) that can capture and better fuse features at different scales to generate more representative features. Experimental results on the CUB200 and MIT indoor67 datasets achieve state-of-the-art performance (CUB200: 94.31% and MIT indoor67: 92.11%).

6.
Sensors (Basel) ; 23(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37514749

RESUMO

The near-space atmosphere is thin, and the atmospheric refraction and scattering on optical observation is very small, making it very suitable for wide-area and high-resolution surveillance using high-altitude balloon platforms. This paper adopts a 9344 × 7000 CMOS sensor to obtain high-resolution images, generating large-field-of-view imaging through the swing scanning of the photoelectric sphere and image stitching. In addition, a zoom lens is designed to achieve flexible applications for different scenarios, such as large-field-of-view and high-resolution imaging. The optical design results show that the camera system has good imaging quality within the focal length range of 320 mm-106.7 mm, and the relative distortion values at different focal lengths are less than 2%. The flight results indicate that the system can achieve seamless image stitching at a resolution of 0.2 m@20 km and the imaging field of view angle exceeds 33°. This system will perform other near-space flight experiments to verify its ultra-wide (field of view exceeding 100°) high-resolution imaging application.

7.
J Am Chem Soc ; 144(22): 10075-10079, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35617523

RESUMO

Developmental self-assembly of DNA nanostructures provides an ideal platform for studying the power and programmability of kinetically controlled structural growth in engineered molecular systems. Triggered initiation and designated sequencing of assembly and disassembly steps have been demonstrated in structures with branches and loops. Here we introduce a new strategy for selectively activating distinct subroutines in a developmental self-assembly program, allowing structures with distinct properties to be created in response to various molecular signals. We demonstrate this strategy in triggered self-assembly of a DNA ring, the size and growth direction of which are responsive to a key molecule. We articulate that reversible assembly steps with slow kinetics at appropriate locations in a reaction pathway could enable multiple populations of structures with stimulus-responsive properties to be simultaneously created in one developmental program. These results open up a broad design space for the self-assembly of molecules with adaptive behaviors toward advanced control in synthetic materials and molecular motors.


Assuntos
Nanoestruturas , DNA/química , Cinética , Nanoestruturas/química
8.
J Am Chem Soc ; 144(27): 12443-12449, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35785961

RESUMO

Molecular circuits capable of processing temporal information are essential for complex decision making in response to both the presence and history of a molecular environment. A particular type of temporal information that has been recognized to be important is the relative timing of signals. Here we demonstrate the strategy of temporal memory combined with logic computation in DNA strand-displacement circuits capable of making decisions based on specific combinations of inputs as well as their relative timing. The circuit encodes the timing information on inputs in a set of memory strands, which allows for the construction of logic gates that act on current and historical signals. We show that mismatches can be employed to reduce the complexity of circuit design and that shortening specific toeholds can be useful for improving the robustness of circuit behavior. We also show that a detailed model can provide critical insights for guiding certain aspects of experimental investigations that an abstract model cannot. We envision that the design principles explored in this study can be generalized to more complex temporal logic circuits and incorporated into other types of circuit architectures, including DNA-based neural networks, enabling the implementation of timing-dependent learning rules and opening up new opportunities for embedding intelligent behaviors into artificial molecular machines.


Assuntos
Computadores Moleculares , Lógica , DNA
9.
Artigo em Inglês | MEDLINE | ID: mdl-35679150

RESUMO

A Gram-positive, cellulose-degrading actinobacterium, designed strain NEAU-YM18T, was isolated from rhizosphere soil of wheat (Triticum aestivum L.) sampled in Langfang, Hebei Province, PR China. The novel strain was characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics confirmed that strain NEAU-YM18T belonged to the genus Catellatospora. Cells of strain NEAU-YM18T were observed to contain meso- and 3-hydroxy-diaminopimelic acids as diagnostic cell-wall amino acids. The acyl type of the cell-wall muramic acid was glycolyl. The whole-cell hydrolysates were xylose, glucose and ribose. The phospholipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major fatty acids were iso-C15 : 0, iso-C16 : 0, C18 : 1 ω9c and summed feature 5 (anteiso-C18 : 0/C18 : 2 ω6,9c). The menaquinones were MK-9(H4), MK-9(H6) and MK-9(H2). The DNA G+C content was 71.1 %. The results of 16S rRNA gene sequence and phylogenetic analyses indicated that strain NEAU-YM18T was closely related to Catellatospora chokoriensis 2-25(1)T (98.4 % 16S rRNA gene sequence similarity), Catellatospora vulcania NEAU-JM1T (98.3%) and Catellatospora sichuanensis H14505T (98.3 %) and formed a branch with C. sichuanensis H14505T. Furthermore, the whole genome phylogeny of strain NEAU-YM18T showed that the strain formed an independent clade. The digital DNA-DNA hybridization results between NEAU-YM18T and C. chokoriensis 2-25(1)T, C. vulcania NEAU-JM1T and C. sichuanensis H14505T were 25.0, 24.7 and 24.7 %, respectively, and the whole-genome average nucleotide identity values between them were 81.5, 81.4 and 81.4 %, respectively. These genetic results and some phenotypic characteristics could distinguish strain NEAU-YM18T from its reference strains. In addition, genomic analysis confirmed that strain NEAU-YM18T had the potential to decompose cellulose and produce bioactive compounds. Therefore, strain NEAU-YM18T represents a novel species of the genus Catellatospora, for which the name Catellatospora tritici sp. nov. is proposed. The type strain is NEAU-YM18T (=CCTCC AA 2020040T=JCM 33977T).


Assuntos
Actinobacteria , Celulase , Técnicas de Tipagem Bacteriana , Composição de Bases , Celulase/genética , Celulase/metabolismo , Celulose/metabolismo , DNA Bacteriano/genética , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Rizosfera , Análise de Sequência de DNA , Solo , Microbiologia do Solo , Triticum/microbiologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-35666673

RESUMO

A novel cellulase-producing actinobacterium, designated strain NEAU-L178T, was isolated from soil sample collected from Qiqihaer, Heilongjiang Province, PR China. A polyphasic study was carried out to determine the taxonomic status of the strain. On the basis of 16S rRNA gene sequence analysis, strain NEAU-L178T should be classified into the genus Nonomuraea and is closely related to Nonomuraea cavernae SYSU K10005T (99.31 % 16S rRNA gene sequence similarity), Nonomuraea glycinis NEAU-BB2C19T (98.75 %), Nonomuraea guangzhouensis NEAU-ZJ3T (98.75 %) and 'Nonomuraea rhizosphaerae' NEAU-mq18T (98.34 %). The digital DNA-DNA hybridization values between them are 27.1, 26.1, 42.0 and 30.9 %, and the whole-genome average nucleotide identity values between them are 83.1, 82.3, 90.3 and 85.8 %, respectively. The whole-cell hydrolysates contained glucose, ribose, arabinose and madurose. The menaquinones were identified as MK-9(H0), MK-9(H4) and MK-9(H2). The major fatty acids were C16 : 0, iso-C17 : 0 and C17 : 0 10-methyl. The detected polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylinositol and three unidentified phospholipids. The genomic DNA G+C content was 69.7 mol%. In addition, whole-genome analysis indicated that strain NEAU-L178T had the potential to degrade cellulose. Based on the phenotypic, genotypic, chemotaxonomic and phylogenetic data, strain NEAU-L178T can be differentiated from its close phylogenetic relatives and represents a novel species of the genus Nonomuraea, for which the name Nonomuraea aurantiaca sp. nov. is proposed. The type strain is NEAU-L178T (=JCM 34799T=CGMCC 4.7741T).


Assuntos
Actinomycetales , Celulase , Técnicas de Tipagem Bacteriana , Composição de Bases , Celulase/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfatidiletanolaminas , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo , Microbiologia do Solo
11.
Pharmazie ; 77(3): 121-124, 2022 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-35459441

RESUMO

Radiotherapy is a common treatment for lung cancer. However, radiation pneumonitis caused by radiotherapy can affect the quality of life and prognosis of lung cancer patients. miR-513a-3p has been found to sensitize human lung adenocarcinoma cells to chemotherapy by targeting glutathione S-transferase P1 (GSTP1). Here, we found that x-ray induced the apoptosis of BEAS-2B and miR-513a-3p expression in a dose- and time-dependent manner, and miR-513a-3p-mimic significantly increased x-ray induced apoptosis, while miR-513a-3p-inhibitor significantly decreased x-ray induced apoptosis. Dual luciferase gene reporter system showed that miR-513a-3p targeted to inhibit the expression of GSTP1 in BEAS-2B cells. Moreover, knockdown of GSTP1 significantly increased, while overexpression of GSTP1 decreased the apoptosis of BEAS-2B induced by x-ray. Importantly, overexpression of GSTP1 significantly reduced miR-513a-3p-mimic elevated x-ray -induced apoptosis in BEAS-2B cells. In conclusion, x-ray caused increased expression of miR-513a-3p, and miR-513a-3p promoted x-ray-induced apoptosis of human lung cells by inhibiting GSTP1.


Assuntos
Apoptose , Glutationa Transferase , Neoplasias Pulmonares , MicroRNAs , Apoptose/genética , Proliferação de Células , Glutationa Transferase/metabolismo , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , MicroRNAs/genética , MicroRNAs/metabolismo , Qualidade de Vida
12.
J Am Chem Soc ; 143(38): 15567-15571, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34524797

RESUMO

DNA catalysts are fundamental building blocks for diverse molecular information-processing circuits. Allosteric control of DNA catalysts has been developed to activate desired catalytic pathways at desired times. Here we introduce a new type of DNA catalyst that we call a cooperative catalyst: a pair of reversible reactions are employed to drive a catalytic cycle in which two signal species, which can be interpreted as an activator and an input, both exhibit catalytic behavior for output production. We demonstrate the role of a dissociation toehold in controlling the kinetics of the reaction pathway and the significance of a wobble base pair in promoting the robustness of the activator. We show near-complete output production with input and activator concentrations that are 0.1 times the gate concentration. The system involves just a double-stranded gate species and a single-stranded fuel species, as simple as the seesaw DNA catalyst, which has no allosteric control. The simplicity and modularity of the design make the cooperative DNA catalyst an exciting addition to strand-displacement motifs for general-purpose computation and dynamics.


Assuntos
DNA/química , Catálise , Cinética , Modelos Moleculares , Conformação de Ácido Nucleico , Relação Estrutura-Atividade
13.
Arch Microbiol ; 203(6): 3287-3294, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33860851

RESUMO

A Gram-positive, aerobic, non-motile, non-spore-forming, short rod-shaped strain, NEAU-LLCT, was isolated from cow dung in Shangzhi City, Heilongjiang Province, Northeast China and identified by a polyphasic taxonomic study. Colonies was light yellow, round, with entire margin. Strain NEAU-LLCT was grown at 15-45 â„ƒ and pH 6.0-10.0. NaCl concentration ranged from 0 to 5% (W/V). The 16S rRNA gene sequence of NEAU-LLCT showed the high similarities with Microbacterium kyungheense JCM 18735T (98.5%), Microbacterium trichothecenolyticum JCM 1358T (98.3%) and Microbacterium jejuense JCM 18734T (98.2%). The whole-cell sugars were glucose, rhamnose and ribose. The menaquinones contained MK-12 and MK-13. Ornithine, glutamic acid, lysine and a small amount of alanine and glycine were the amino acids in the hydrolyzed products of the cell wall. The major fatty acids were iso-C16:0, iso-C18:0, anteiso-C15:0 and anteiso-C17:0. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The genome of NEAU-LLCT was 4,369,375 bp and G + C content is 70.28 mol%. A combination of DNA-DNA hybridization result and some phenotypic characteristics demonstrated that strain NEAU-LLCT could be distinguished from its closely related strains. Therefore, the strain NEAU-LLCT was considered to represent a novel species, which was named Microbacterium helvum sp. (Type strain NEAU-LLCT = CCTCC AA 2018026T = JCM 32661T).


Assuntos
Microbacterium/isolamento & purificação , Aminoácidos/análise , Animais , Composição de Bases , Bovinos , DNA Bacteriano/química , Ácidos Graxos/química , Fezes/microbiologia , Feminino , Lipídeos/análise , Microbacterium/química , Microbacterium/classificação , Microbacterium/genética , Filogenia , Açúcares/análise
14.
Appl Opt ; 60(26): 8057-8068, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613068

RESUMO

As a common tracer in the atmosphere, airglow can be used as an important means to study the interaction between the lower atmosphere, near space, and ionosphere. In the near-Earth space, the high-altitude balloon can realize long time flight, which makes the airglow detection realize both high range resolution and time resolution. In this paper, a balloon-based multi-band airglow imager is designed, which can observe OI (557.7 nm), Na (589.3 nm), OI (630.0 nm), and OH (720-910 nm) with annular field of view (30° inner ring and 80° outer ring), and its resolution is 500 m at 250 km. The multi-band airglow imager designed in this paper is equipped in the payload cabin and raised to above 30 km for flat flying for more than 6 h. The experimental results show that the imager worked normally, and airglow images were photographed and stored; the optical system can stand the harsh environment in the near space. The multi-band airglow imager designed in this paper will take part in other near-space exploration tasks in the future and obtain corresponding results.

15.
Proc Natl Acad Sci U S A ; 115(5): 903-908, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29339484

RESUMO

A natural feature of molecular systems is their inherent stochastic behavior. A fundamental challenge related to the programming of molecular information processing systems is to develop a circuit architecture that controls the stochastic states of individual molecular events. Here we present a systematic implementation of probabilistic switching circuits, using DNA strand displacement reactions. Exploiting the intrinsic stochasticity of molecular interactions, we developed a simple, unbiased DNA switch: An input signal strand binds to the switch and releases an output signal strand with probability one-half. Using this unbiased switch as a molecular building block, we designed DNA circuits that convert an input signal to an output signal with any desired probability. Further, this probability can be switched between 2 n different values by simply varying the presence or absence of n distinct DNA molecules. We demonstrated several DNA circuits that have multiple layers and feedback, including a circuit that converts an input strand to an output strand with eight different probabilities, controlled by the combination of three DNA molecules. These circuits combine the advantages of digital and analog computation: They allow a small number of distinct input molecules to control a diverse signal range of output molecules, while keeping the inputs robust to noise and the outputs at precise values. Moreover, arbitrarily complex circuit behaviors can be implemented with just a single type of molecular building block.

16.
Int J Syst Evol Microbiol ; 70(5): 3096-3104, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32242796

RESUMO

A novel actinobacterium, designated strain NEAU-7082T, was isolated from rhizosphere soil of wheat (Triticum aestivum L.) and characterized by using a polyphasic approach. Morphological and chemotaxonomic characteristics confirmed the affiliation of strain NEAU-7082T to the genus Glycomyces. 16S rRNA gene sequence analysis indicated that strain NEAU-7082T belonged to the genus Glycomyces and was closely related to Glycomyces mayteni JCM 16217T (99.0 % 16S rRNA gene sequence similarity), Glycomyces sambucus DSM 45047T (98.4 %), Glycomyces scopariae DSM 44968T (98.3 %), Glycomyces paridis DSM 102295T (98.1 %), Glycomyces artemisiae NBRC 109773T (98.0 %) and Glycomyces dulcitolivorans DSM 105121T (97.9 %). Phylogenetic analysis using the 16S rRNA gene sequence showed that the strain formed a stable clade with G. mayteni JCM 16217T and clustered with G. sambucus DSM 45047T, G. scopariae DSM 44968T, G. artemisiae NBRC 109773T and G. dulcitolivorans DSM 105121T in the genus Glycomyces. The cell wall contained meso-diaminopimelic acid and the whole-cell hydrolysates were glucose and xylose. The polar lipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), glycolipid (GL), phosphatidylinositol mannoside (PIM) and an unidentified lipid (UL). The menaquinones were MK-11(H4), MK-11 and MK-10. Major fatty acids were anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. These chemotaxonomic data substantiated the affiliation of strain NEAU-7082T to the genus Glycomyces. The DNA G+C content was 71.3 mol%. A combination of DNA-DNA hybridization results and some phenotypic characteristics demonstrated that strain NEAU-7082T could be distinguished from its closest relatives. Therefore, strain NEAU-7082T is considered to represent a novel species of the genus Glycomyces, for which the name Glycomyces albidus sp. nov. is proposed. The type strain is NEAU-7082T (=CCTCC AA 2019045T=JCM 33458T).


Assuntos
Actinomycetales/classificação , Filogenia , Rizosfera , Microbiologia do Solo , Triticum/microbiologia , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/química
17.
Sensors (Basel) ; 20(7)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272781

RESUMO

As a kind of large-scale unmanned aerial vehicle, a high-altitude balloon can carry a large load up to tens of kilometers in the near space for a long time, which brings a new way for the stratosphere atmospheric detection. In order to provide a suitable working environment for the near-space detection load, it is necessary to design a sensor system based on a high-altitude balloon, which is used to provide environmental temperature, height position, and attitude information, current working, and video surveillance. The high-altitude balloon-based sensor system designed in this paper had participated in the near-space flight experiment, whose total flight time was 30 h and 53 min, and the horizontal flight time was 28 h and 58 min crossing the day and night. The high-altitude balloon-based sensor system had withstood the severe environment of the near-space during the day and night, providing accurate temperature measurement, real-time altitude position and attitude data acquisition, reliable current monitoring, and comprehensive video surveillance. In the next three years, the high-altitude balloon-based sensor system developed in this paper will continue to participate in the experiment and provide support for more detection loads.

18.
Int J Syst Evol Microbiol ; 69(11): 3500-3507, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31418680

RESUMO

A novel actinobacterium, designated strain NEAU-THZ27T, was isolated from soil collected from the Cornel peak in Jiaozuo, Henan Province, PR China and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics of the strain coincided with those of members of the genusKribbella. The results of 16S rRNA gene sequence analysis showed that strain NEAU-THZ27T belongs to the genus Kribbella and was most closely related to Kribbella podocarpi YPL1T (98.96 %), Kribbella karoonensis Q41T (98.89 %), Kribbella aluminosa HKI 0478T (98.86%) and Kribbella hippodromi S1.4T (98.85 %), similarities to other type strains of species of the genus Kribbella were found to be less than 98.7 %. Phylogenetic analyses using the 16S rRNA gene sequence and multilocus sequence analysis using the concatenated gene sequences of the gyrB, rpoB, recA, relA and atpD genes all showed that the strain formed a separate branch in the genus Kribbella. The cell wall contained ll-diaminopimelic acid as the major diamino acid and the whole-cell hydrolysates were ribose and glucose. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol. The predominant menaquinone was MK-9(H4). Major fatty acids were iso-C16 : 0, iso-C14 : 0 and anteiso-C15 : 0, these chemotaxonomic data supported the affiliation of strain NEAU-THZ27T to the genus Kribbella. The DNA G+C content was 68.0 mol%. Furthermore, the strain could be clearly distinguished by concatenated gene genetic distances, the combination of DNA-DNA hybridization results and some phenotypic characteristics. Therefore, it is proposed that strain NEAU-THZ27T represents a novel species of the genus Kribbella, for which the name Kribbella jiaozuonensis sp. nov. is proposed. The type strain is NEAU-THZ27T (=CGMCC 4.7504T=DSM 105535T).


Assuntos
Actinobacteria/classificação , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Genes Bacterianos , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
Antonie Van Leeuwenhoek ; 112(5): 703-710, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30465323

RESUMO

Three Gram-stain positive, aerobic actinomycete strains, designated NEAU-A15T, NEAU-A13 and NEAU-C4, were isolated from rhizosphere soil of wheat (Triticum aestivum L.) collected from Langfang, Hebei Province, China. Based on their morphological characteristics, biochemical features and molecular phylogenetic studies, these strains were concluded to belong to a new member of the genus Glycomyces. 16S rRNA gene sequence analysis showed that strain NEAU-A15T shares 99.91% and 99.80% 16S rRNA gene sequence similarity with NEAU-A13 and NEAU-C4, respectively, and these three strains showed high sequence similarities to Glycomyces algeriensis DSM 44727T (99.24, 99.45, 99.38%), Glycomyces lechevalierae DSM 44724T (98.97, 99.17, 99.11%) and Glycomyces rutgersensis DSM 43812T (98.83, 99.04, 98.97%). Phylogenetic analysis indicated that these three strains clustered together and formed a cluster with Glycomyces tritici NEAU-C2T (97.30, 97.73, 99.48%), G. algeriensis DSM 44727T, G. lechevalierae DSM 44724T and G. rutgersensis DSM 43812T. These three strains were observed to contain MK-10(H2), MK-10(H6) and MK-11 as menaquinones. The whole cell sugar profiles were found to contain galactose, ribose and xylose. The polar lipids were found to consist of diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, phosphoglycolipid, phosphatidylinositol mannoside and an unidentified glycolipid. The major fatty acids were identified as anteiso-C15:0, iso-C16:0, anteiso-C17:0 and iso-C15:0. The DNA-DNA hybridization values between strain NEAU-A15T and NEAU-A13/NEAU-C4 were 86.2 ± 2.3% and 83.4 ± 3.5%, respectively. The values between these three strains and their close phylogenetic relatives were 48-52%, supporting the conclusion that they belong to a distinct genomic species. An array of phenotypic characteristics also differentiated these isolates from their closely related species. On the basis of the genetic and phenotypic properties, strains NEAU-A15T, NEAU-A13 and NEAU-C4 can be classified as representatives of a novel species of the genus Glycomyces, for which the name Glycomyces luteolus sp. nov., is proposed. The type strain is NEAU-A15T (= DSM 104643T = CGMCC 4.7394T).


Assuntos
Actinobacteria/isolamento & purificação , Microbiologia do Solo , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/metabolismo , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Rizosfera , Solo/química , Triticum/crescimento & desenvolvimento
20.
J Am Chem Soc ; 140(50): 17361-17364, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30512944

RESUMO

DNA origami tilings provide methods for creating complex molecular patterns and shapes using flat DNA origami structures as building blocks. Square tiles have been developed to construct micrometer-scale arrays and to generate patterns using stochastic or deterministic strategies. Here we show triangular tiles as a complementary approach for enriching the design space of DNA tilings and for extending the shape of the self-assembled arrays from 2D to 3D. We introduce a computational approach for maximizing binding specificity in a fully symmetric tile design, with which we construct a 20-tile structure resembling a rhombic triacontahedron. We demonstrate controlled transition between 3D and 2D structures using simple methods including tile concentration, magnesium, and fold symmetry in tile edge design. Using these approaches, we construct 2D arrays with unbounded and designed sizes. The programmability of the edge design and the flexibility of the structure make the triangular DNA origami tile an ideal building block for complex self-assembly and reconfiguration in artificial molecular machines and fabricated nanodevices.


Assuntos
DNA de Cadeia Simples/química , Nanoestruturas/química , Algoritmos , Sequência de Bases , Microscopia de Força Atômica , Nanotecnologia/métodos , Conformação de Ácido Nucleico
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