scholarly journals FurA-Dependent Microcystin Synthesis under Copper Stress in Microcystis aeruginosa

2020 ◽  
Vol 8 (6) ◽  
pp. 832
Author(s):  
Yuanyuan Chen ◽  
Jiaojiao Yin ◽  
Jin Wei ◽  
Xuezhen Zhang
Keyword(s):  
Microcystis Aeruginosa ◽  
Iron Uptake ◽  
Copper Ions ◽  
Copper Ion ◽  
Underlying Mechanism ◽  
Cyanobacterial Blooms ◽  
Copper Stress ◽  
Rna Seq ◽  
Treatment Groups ◽  
The Relationship

Massive blooms of cyanobacteria frequently occur with microcystin (MC) production. Cyanobacteria are exposed to copper stresses such as copper algaecides which are often used to remove cyanobacterial blooms. However, copper increased the MC production of cyanobacteria, and the underlying mechanism remains unclear. The present study investigated the relationship between copper exposure (0.5 and 3 µM) and MC synthesis in Microcystis aeruginosa PCC 7806. The study concluded that the content of intracellular MCs increased by nearly two times both in 0.5 and 3 µM copper. High-throughput RNA sequencing (RNA-seq) provided evidence that copper mainly attacked Fe–S clusters, with evidence of changes in iron, sulfur, iron uptake regulators (fur), glutaredoxins and dehydratase genes. The transcription of numbers of genes implicated in iron uptake, MC synthesis and furA was also evaluated with quantitative real-time PCR (qRT-PCR). In these three Cu treatment groups, the amount of MCs increased as copper elevated. As the expression of mcyD gene was directly regulated by FurA and copper ions affected the expression of the FurA-related genes, we believed that MC synthesis genes were controlled by copper. This study has made a further understanding of the mechanism of the increase in MC synthesis of M. aeruginosa PCC 7806 treated with copper-based algaecides. We aimed to understand the mechanism of copper ion influencing the synthesis of MCs.

ExperimentSubset: an R package to manage subsets of Bioconductor Experiment objects

2021 ◽  
Author(s):  
Irzam Sarfraz ◽  
Muhammad Asif ◽  
Joshua D Campbell
Keyword(s):  
Single Cell ◽  
R Package ◽  
Poor Quality ◽  
Data Matrix ◽  
Supplementary Information ◽  
Data Provenance ◽  
Rna Seq ◽  
Efficient Management ◽  
The Matrix ◽  
The Relationship

Abstract Motivation R Experiment objects such as the SummarizedExperiment or SingleCellExperiment are data containers for storing one or more matrix-like assays along with associated row and column data. These objects have been used to facilitate the storage and analysis of high-throughput genomic data generated from technologies such as single-cell RNA sequencing. One common computational task in many genomics analysis workflows is to perform subsetting of the data matrix before applying down-stream analytical methods. For example, one may need to subset the columns of the assay matrix to exclude poor-quality samples or subset the rows of the matrix to select the most variable features. Traditionally, a second object is created that contains the desired subset of assay from the original object. However, this approach is inefficient as it requires the creation of an additional object containing a copy of the original assay and leads to challenges with data provenance. Results To overcome these challenges, we developed an R package called ExperimentSubset, which is a data container that implements classes for efficient storage and streamlined retrieval of assays that have been subsetted by rows and/or columns. These classes are able to inherently provide data provenance by maintaining the relationship between the subsetted and parent assays. We demonstrate the utility of this package on a single-cell RNA-seq dataset by storing and retrieving subsets at different stages of the analysis while maintaining a lower memory footprint. Overall, the ExperimentSubset is a flexible container for the efficient management of subsets. Availability and implementation ExperimentSubset package is available at Bioconductor: https://bioconductor.org/packages/ExperimentSubset/ and Github: https://github.com/campbio/ExperimentSubset. Supplementary information Supplementary data are available at Bioinformatics online.

scholarly journals Chemical Characterization of Microcystis aeruginosa for Feed and Energy Uses

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3013
Author(s):  
Larissa Souza Passos ◽  
Éryka Costa Almeida ◽  
Claudio Martin Pereira de Pereira ◽  
Alessandro Alberto Casazza ◽  
Attilio Converti ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
Animal Feed ◽  
Renewable Energy Sources ◽  
Chemical Characterization ◽  
Cyanobacterial Blooms ◽  
Energy Sources ◽  
Carbohydrate Source ◽  
Heating Value ◽  
Adverse Health Effects ◽  
Degradation Reactions

Cyanobacterial blooms and strains absorb carbon dioxide, drawing attention to its use as feed for animals and renewable energy sources. However, cyanobacteria can produce toxins and have a low heating value. Herein, we studied a cyanobacterial strain harvested during a bloom event and analyzed it to use as animal feed and a source of energy supply. The thermal properties and the contents of total nitrogen, protein, carbohydrate, fatty acids, lipid, and the presence of cyanotoxins were investigated in the Microcystis aeruginosa LTPNA 01 strain and in a bloom material. Microcystins (hepatotoxins) were not detected in this strain nor in the bloom material by liquid chromatography coupled to mass spectrometry. Thermogravimetric analysis showed that degradation reactions (devolatilization) initiated at around 180 °C, dropping from approximately 90% to 20% of the samples’ mass. Our work showed that despite presenting a low heating value, both biomass and non-toxic M. aeruginosa LTPNA 01 could be used as energy sources either by burning or producing biofuels. Both can be considered a protein and carbohydrate source similar to some microalgae species as well as biomass fuel. It could also be used as additive for animal feed; however, its safety and potential adverse health effects should be further investigated.

scholarly journals Identification of the specific long-noncoding RNAs involved in night-break mediated flowering retardation in Chenopodium quinoa

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Qi Wu ◽  
Yiming Luo ◽  
Xiaoyong Wu ◽  
Xue Bai ◽  
Xueling Ye ◽  
...  
Keyword(s):  
Expression Profiles ◽  
Functional Characterization ◽  
Chenopodium Quinoa ◽  
Noncoding Rnas ◽  
Long Noncoding Rnas ◽  
Rna Seq ◽  
Short Day ◽  
Homologous Genes ◽  
The Relationship ◽  
Encoding Genes

Abstract Background Night-break (NB) has been proven to repress flowering of short-day plants (SDPs). Long-noncoding RNAs (lncRNAs) play key roles in plant flowering. However, investigation of the relationship between lncRNAs and NB responses is still limited, especially in Chenopodium quinoa, an important short-day coarse cereal. Results In this study, we performed strand-specific RNA-seq of leaf samples collected from quinoa seedlings treated by SD and NB. A total of 4914 high-confidence lncRNAs were identified, out of which 91 lncRNAs showed specific responses to SD and NB. Based on the expression profiles, we identified 17 positive- and 7 negative-flowering lncRNAs. Co-expression network analysis indicated that 1653 mRNAs were the common targets of both types of flowering lncRNAs. By mapping these targets to the known flowering pathways in model plants, we found some pivotal flowering homologs, including 2 florigen encoding genes (FT (FLOWERING LOCUS T) and TSF (TWIN SISTER of FT) homologs), 3 circadian clock related genes (EARLY FLOWERING 3 (ELF3), LATE ELONGATED HYPOCOTYL (LHY) and ELONGATED HYPOCOTYL 5 (HY5) homologs), 2 photoreceptor genes (PHYTOCHROME A (PHYA) and CRYPTOCHROME1 (CRY1) homologs), 1 B-BOX type CONSTANS (CO) homolog and 1 RELATED TO ABI3/VP1 (RAV1) homolog, were specifically affected by NB and competed by the positive and negative-flowering lncRNAs. We speculated that these potential flowering lncRNAs may mediate quinoa NB responses by modifying the expression of the floral homologous genes. Conclusions Together, the findings in this study will deepen our understanding of the roles of lncRNAs in NB responses, and provide valuable information for functional characterization in future.

scholarly journals Evidence of Quorum Sensing in Cyanobacteria by Homoserine Lactones: The Origin of Blooms

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1831
Author(s):  
Natalia Herrera ◽  
Fernando Echeverri
Keyword(s):  
Cell Proliferation ◽  
Quorum Sensing ◽  
Microcystis Aeruginosa ◽  
Industrial Effluents ◽  
Cyanobacterial Blooms ◽  
Cylindrospermopsis Raciborskii ◽  
Bacterial Communication ◽  
Homoserine Lactones ◽  
Exogenous Compounds ◽  
Almost All

Although several theories have been postulated to explain cyanobacterial blooms, their biochemical origin has not yet been found. In this work, we explore the existence of bacterial communication, called quorum sensing, in Microcystis aeruginosa and Cylindrospermopsis raciborskii. Thus, the application of several known acylhomoserine lactones to cultures of both cyanobacteria causes profound metabolic. At 72 h post-application, some of them produced substantial increases in cell proliferation, while others were inhibitors. There was a correlation with colony-forming activity for most of them. According to ELISA analysis, the microcystin levels were increased with some lactones. However, there was a clear difference between M. aeruginosa and C. raciborskii culture since, in the first one, there was an inducing effect on cell proliferation, while in C. raciborskii, the effects were minor. Besides, there were compound inhibitors and inducers of microcystins production in M. aeruginosa, but almost all compounds were only inducers of saxitoxin production in C. raciborskii. Moreover, each lactone appears to be involved in a specific quorum sensing process. From these results, the formation of cyanobacterial blooms in dams and reservoirs could be explained since lactones may come from cyanobacteria and other sources as bacterial microflora-associated or exogenous compounds structurally unrelated to lactones, such as drugs, industrial effluents, and agrochemicals.

scholarly journals An Investigation on Design and Characterization of a Highly Selective LED Optical Sensor for Copper Ions in Aqueous Solutions

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1099
Author(s):  
Sheng-Chun Hung ◽  
Chih-Cheng Lu ◽  
Yu-Ting Wu
Keyword(s):  
Aqueous Solutions ◽  
Metal Ions ◽  
Copper Ions ◽  
Incident Light ◽  
Copper Ion ◽  
Intensity Change ◽  
Optical Absorbance ◽  
Sensing System ◽  
Optic Sensor ◽  
Cu Ions

The optical characteristics of copper ion detection, such as the photometric absorbance of specific wavelengths, exhibit significant intensity change upon incident light into the aqueous solutions with different concentrations of metal ions due to the electron transition in the orbit. In this study, we developed a low-cost, small-size and fast-response photoelectric sensing prototype as an optic sensor for copper (Cu) ions detection by utilizing the principle of optical absorption. We quantified the change of optical absorbance from infra-red (IR) light emitting diodes (LEDs) upon different concentrations of copper ions and the transmitted optical signals were transferred to the corresponding output voltage through a phototransistor and circuit integrated in the photoelectric sensing system. The optic sensor for copper (Cu) ions demonstrated not only excellent specificity with other metal ions such as cadmium (Cd), nickel (Ni), iron (Fe) and chloride (Cl) ions in the same aqueous solution but also satisfactory linearity and reproducibility. The sensitivity of the preliminary sensing system for copper ions was 29 mV/ppm from 0 to 1000 ppm. In addition, significant ion-selective characteristics and anti-interference capability were also observed in the experiments by the proposed approach.

scholarly journals lncRNA CASC19 Contributes to Radioresistance of Nasopharyngeal Carcinoma by Promoting Autophagy via AMPK-mTOR Pathway

2021 ◽  
Vol 22 (3) ◽  
pp. 1407
Author(s):  
Hongxia Liu ◽  
Wang Zheng ◽  
Qianping Chen ◽  
Yuchuan Zhou ◽  
Yan Pan ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Cell Line ◽  
Malignant Tumors ◽  
Underlying Mechanism ◽  
Mtor Pathway ◽  
Rna Seq ◽  
Cellular Autophagy ◽  
First Time

Nasopharyngeal carcinoma (NPC) is one of the most frequent head and neck malignant tumors and is majorly treated by radiotherapy. However, radiation resistance remains a serious obstacle to the successful treatment of NPC. The aim of this study was to discover the underlying mechanism of radioresistance and to elucidate novel genes that may play important roles in the regulation of NPC radiosensitivity. By using RNA-seq analysis of NPC cell line CNE2 and its radioresistant cell line CNE2R, lncRNA CASC19 was screened out as a candidate radioresistance marker. Both in vitro and in vivo data demonstrated that a high expression level of CASC19 was positively correlated with the radioresistance of NPC, and the radiosensitivity of NPC cells was considerably enhanced by knockdown of CASC19. The incidence of autophagy was enhanced in CNE2R in comparison with CNE2 and another NPC cell line HONE1, and silencing autophagy with LC3 siRNA (siLC3) sensitized NPC cells to irradiation. Furthermore, CASC19 siRNA (siCASC19) suppressed cellular autophagy by inhibiting the AMPK/mTOR pathway and promoted apoptosis through the PARP1 pathway. Our results revealed for the first time that lncRNA CASC19 contributed to the radioresistance of NPC by regulating autophagy. In significance, CASC19 might be a potential molecular biomarker and a new therapeutic target in NPC.

Consumers Complain More Fiercely Through Small-Screen Devices: The Role of Spatial Crowding Perception

2020 ◽  
Vol 23 (3) ◽  
pp. 353-367
Author(s):  
Yuanyuan Zhou ◽  
Bin Tian ◽  
Tingting Mo ◽  
Zhuoying Fei
Keyword(s):  
Secondary Data ◽  
Underlying Mechanism ◽  
Screen Size ◽  
Design Elements ◽  
Perception Theory ◽  
Fourth Experiment ◽  
Complaint Behavior ◽  
The Relationship ◽  
Small Screen

Previous research has mainly focused on the determinants of consumers’ complaint channel choices. Little attention has been paid to the behavioral consequences of different complaint channels, particularly different complaint devices. Drawing on spatial crowding perception theory, this study finds that in an online complaint context, consumers’ complaint intensity is shaped by complaint devices that differ in screen size. Crowding perception produced by visually restrictive tension mediates the relationship between the screen size of the complaint device and the complaint intensity. The results of secondary data confirm that consumers’ complaint intensity is higher while complaining through a small-screen device (as opposed to a large-screen one). Three scenario-based experiments are conducted to examine the role of perceived spatial crowding in producing a more intense complaint behavior when complaints are submitted through smaller screen devices (as opposed to larger screen devices). The fourth experiment reveals that crowding perception can be lessened by adjusting certain design elements of the interface, ultimately mitigating the intensity of the complaint submitted through a small-screen device. Our research identifies the specific causality and underlying mechanism of the influence of device type on consumers’ postconsumption behavior, thus contributing to clarify some ambiguities in the literature.

Mediating Effect of WhatsApp Addiction Between Social Loneliness and Preference for Online Social Interaction: A Cross-cultural Study

2021 ◽  
pp. 097215092110556
Author(s):  
Komal Nagar ◽  
Gurmeet Singh ◽  
Rabinder Singh
Keyword(s):  
Social Interaction ◽  
Underlying Mechanism ◽  
Mediating Effect ◽  
Mediating Role ◽  
Cross Cultural Study ◽  
Online Social Interaction ◽  
The Relationship ◽  
Moderating Role ◽  
Social Loneliness

The present study aims to explore the relationship between social loneliness and online interaction through WhatsApp addiction among a sample of Indian and Fijian respondents. Based on the responses of 202 Indian and 73 Fijian respondents, the present research study validated the mediating role of WhatsApp addiction, revealing that social loneliness increased the possibility of preferring to interact online through increased WhatsApp addiction. The empirical results showed that the underlying mechanism of social loneliness might indirectly influence consumers’ preference for online social interaction (POSI). The study further assessed the moderating role of culture in the association between social loneliness and POSI. Findings of the moderated mediation analysis demonstrated that, the association between loneliness and preference to socialize online differed, based on the identified cultural differences between Indian and Fijian groups.

Tapping the Power of Social Media on Innovation Performance

2021 ◽  
Vol 9 (2) ◽  
pp. 143-151
Author(s):  
Shan Shan Teh ◽  
Daisy Mui Hung Kee ◽  
Munazza Zahra ◽  
Gadi Dung Paul
Keyword(s):  
Social Media ◽  
Data Collection ◽  
Open Innovation ◽  
Underlying Mechanism ◽  
Jel Classification ◽  
Innovation Performance ◽  
Great Idea ◽  
New Evidence ◽  
The Relationship ◽  
Innovation Impact

Objective - This study investigates the relationship between social media and innovation performance among SMEs in Malaysia. This study also extends social media literature by investigating the underlying mechanism of open innovation in the relationship between social media and innovation performance. Methodology/Technique - A questionnaire was used to collect data from the respondents. A total of 173 samples from data collection were then used to test the hypotheses by using the SPSS and SmartPLS software. Finding - The result has revealed that social media has a significant effect on innovation performance. Besides, outbound innovation is also found to mediate the relationship between social media and innovation performance. Novelty - This study contributes to the literature on social media and innovation by providing new evidence regarding outbound innovation impact on performance among SMEs. It also provides a great idea of social media's importance to SME managers in improving innovation performance in an organization. Type of Paper - Empirical. Keywords: Social Media, Innovation Performance, Open Innovation, Smes, Malaysia JEL Classification: URI: http://gatrenterprise.com/GATRJournals/GJBSSR/vol9.2_4.html DOI: https://doi.org/10.35609/gjbssr.2021.9.2(4) Pages 143 – 151

Biomimetic synthesis of needle-like fluorescent calcium phosphate/carbon dot hybrid composites for cell labeling and copper ion detection

2016 ◽  
Vol 45 (18) ◽  
pp. 7665-7671 ◽  
Author(s):  
Shanshan Guo ◽  
Shousi Lu ◽  
Pingxiang Xu ◽  
Yi Ma ◽  
Liang Zhao ◽  
...  
Keyword(s):  
Drinking Water ◽  
Calcium Phosphate ◽  
Copper Ions ◽  
Hybrid Composites ◽  
Copper Ion ◽  
Cell Labeling ◽  
Biomimetic Synthesis ◽  
Selective Detection ◽  
Sodium Carboxymethylcellulose ◽  
Biomimetic Method

We report a biomimetic method to synthesize needle-like calcium phosphate (CaP) using carbon dots (CDs) and sodium carboxymethylcellulose as dual templates. The CaP/CDs were capable of cell labeling and selective detection of copper ions in drinking water.

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