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101.
Pheasant reintroduction and conservation efforts have been in place in Pakistan since the 1980 s, yet there is still a scarcity of data on pheasant microbiome and zoonosis. Instead of growing vast numbers of bacteria in the laboratory, to investigate the fecal microbiome, pheasants (green and ring neck pheasant) were analyzed using 16S rRNA metagenomics and using IonS5TMXL sequencing from two flocks more than 10 birds. Operational taxonomic unit (OTU) cluster analysis and phylogenetic tree analysis was performed using Mothur software against the SSUrRNA database of SILVA and the MUSCLE (Version 3.8.31) software. Results of the analysis showed that firmicutes were the most abundant phylum among the top ten phyla, in both pheasant species, followed by other phyla such as actinobacteria and proteobacteria in ring necked pheasant and bacteroidetes in green necked pheasant. Bacillus was the most relatively abundant genus in both pheasants followed by Oceanobacillus and Teribacillus for ring necked pheasant and Lactobacillus for green necked pheasant. Because of their well-known beneficial characteristics, these genus warrants special attention. Bird droppings comprise germs from the urinary system, gut, and reproductive sites, making it difficult to research each anatomical site at the same time. We conclude that metagenomic analysis and classification provides baseline information of the pheasant fecal microbiome that plays a role in disease and health.  相似文献   
102.
Post-translational modification of proteins by lysine acetylation plays important regulatory roles in living cells. The budding yeast Saccharomyces cerevisiae is a widely used unicellular eukaryotic model organism in biomedical research. S. cerevisiae contains several evolutionary conserved lysine acetyltransferases and deacetylases. However, only a few dozen acetylation sites in S. cerevisiae are known, presenting a major obstacle for further understanding the regulatory roles of acetylation in this organism. Here we use high resolution mass spectrometry to identify about 4000 lysine acetylation sites in S. cerevisiae. Acetylated proteins are implicated in the regulation of diverse cytoplasmic and nuclear processes including chromatin organization, mitochondrial metabolism, and protein synthesis. Bioinformatic analysis of yeast acetylation sites shows that acetylated lysines are significantly more conserved compared with nonacetylated lysines. A large fraction of the conserved acetylation sites are present on proteins involved in cellular metabolism, protein synthesis, and protein folding. Furthermore, quantification of the Rpd3-regulated acetylation sites identified several previously known, as well as new putative substrates of this deacetylase. Rpd3 deficiency increased acetylation of the SAGA (Spt-Ada-Gcn5-Acetyltransferase) complex subunit Sgf73 on K33. This acetylation site is located within a critical regulatory domain in Sgf73 that interacts with Ubp8 and is involved in the activation of the Ubp8-containing histone H2B deubiquitylase complex. Our data provides the first global survey of acetylation in budding yeast, and suggests a wide-ranging regulatory scope of this modification. The provided dataset may serve as an important resource for the functional analysis of lysine acetylation in eukaryotes.Lysine acetylation is a dynamic and reversible post-translational modification. Acetylation of lysines on their ε-amino group is catalyzed by lysine acetyltransferases (KATs1, also known as histone acetyltrasferases (HATs)), and reversed by lysine deacetylases (KDACs, also known as histone deacetylases (HDACs)) (1). The enzymatic machinery involved in lysine acetylation is evolutionary conserved in all forms of life (24). The role of acetylation has been extensively studied in the regulation of gene expression via modification of histones (5). Acetylation also plays important roles in controlling cellular metabolism (610), protein folding (11), and sister chromatid cohesion (12). Furthermore, acetylation has been implicated in regulating the beneficial effects of calorie restriction (13), a low nutrient diet without starvation, and aging. Based on these findings, it is proposed that the functional roles of acetylation in these processes are evolutionary conserved from yeast to mammals.Advancements in mass spectrometry (MS)-based proteomics have greatly facilitated identification of thousands of post-translational modification (PTM) sites in eukaryotic cells (1418). Proteome-wide mapping of PTM sites can provide important leads for analyzing the functional relevance of individual sites and a systems-wide view of the regulatory scope of post-translational modifications. Also, large-scale PTM datasets are an important resource for the in silico analysis of PTMs, which can broaden the understanding of modification site properties and their evolutionary trajectories.The budding yeast Saccharomyces cerevisiae is a commonly used unicellular eukaryotic model organism. Yeast has been used in many pioneering “-omics” studies, including sequencing of the first eukaryotic genome (19), systems-wide genetic interactions analysis (20, 21), MS-based comprehensive mapping of a eukaryotic proteome (22), and proteome-wide analysis of protein-protein interactions (23, 24). In addition, S. cerevisiae has been extensively used to study the molecular mechanisms of acetylation. Many lysine acetyltransferases and deacetylases were discovered in this organism (2, 25), and their orthologs were subsequently identified in higher eukaryotes. Furthermore, the functional roles of many well-studied acetylation sites on histones are conserved from yeast to mammals. Recent data from human and Drosophila cells show that acetylation is present on many highly conserved metabolic enzymes (2628). However, only a few dozen yeast acetylation sites are annotated in the Uniprot database. Given the presence of a well-conserved and elaborate acetylation machinery in yeast, we reasoned that many more acetylation sites exist in this organism that remained to be identified.Here we used high resolution mass spectrometry-based proteomics to investigate the scope of acetylation in S. cerevisiae. We identified about 4000 unique acetylation sites in this important model organism. Bioinformatic analysis of yeast acetylation sites and comparison with previously identified human and Drosophila acetylation sites indicates that many acetylation sites are evolutionary conserved. Furthermore, quantitative analysis of the Rpd3-regulated acetylation sites identified several nuclear proteins that showed increased acetylation in rpd3 knockout cells. Our results provide a systems-wide view of acetylation in budding yeast, and a rich dataset for functional analysis of acetylation sites in this organism.  相似文献   
103.
Vibrio cholerae is a noninvasive intestinal pathogen extensively studied as the causative agent of the human disease cholera. Our recent work identified MakA as a potent virulence factor of V. cholerae in both Caenorhabditis elegans and zebrafish, prompting us to investigate the potential contribution of MakA to pathogenesis also in mammalian hosts. In this study, we demonstrate that the MakA protein could induce autophagy and cytotoxicity of target cells. In addition, we observed that phosphatidic acid (PA)-mediated MakA-binding to the host cell plasma membranes promoted macropinocytosis resulting in the formation of an endomembrane-rich aggregate and vacuolation in intoxicated cells that lead to induction of autophagy and dysfunction of intracellular organelles. Moreover, we functionally characterized the molecular basis of the MakA interaction with PA and identified that the N-terminal domain of MakA is required for its binding to PA and thereby for cell toxicity. Furthermore, we observed that the ΔmakA mutant outcompeted the wild-type V. cholerae strain A1552 in the adult mouse infection model. Based on the findings revealing mechanistic insights into the dynamic process of MakA-induced autophagy and cytotoxicity we discuss the potential role played by the MakA protein during late stages of cholera infection as an anti-colonization factor.  相似文献   
104.
Bashir  Faiza  Rehman  Ateeq Ur  Szabó  Milán  Vass  Imre 《Photosynthesis research》2021,149(1-2):93-105
Photosynthesis Research - Singlet oxygen (1O2) is an important damaging agent, which is produced during illumination by the interaction of the triplet excited state pigment molecules with molecular...  相似文献   
105.
Proniosomes (PN) are the dry water-soluble carrier systems that may enhance the oral bioavailability, stability, and topical permeability of therapeutic agents. The low solubility and low oral bioavailability due to extensive first pass metabolism make Pentazocine as an ideal candidate for oral and topical sustained release delivery. The present study was aimed to formulate the PNs by quick slurry method that are converted to niosomes (liquid dispersion) by hydration, and subsequently formulated to semisolid niosomal gel. The PNs were found in spherical shape in the SEM and stable in the physicochemical and thermal analysis (FTIR, TGA, and XRD). The quick slurry method produced high recovery (>?80% yield) and better flow properties (θ?=?28.1–37.4°). After hydration, the niosomes exhibited desirable entrapment efficiency (44.45–76.23%), size (4.98–21.3 μm), and zeta potential (??9.81 to ??21.53 mV). The in vitro drug release (T100%) was extended to more than three half-lives (2–4 h) and showed good fit to Fickian diffusion indicated by Korsmeyer-Peppas model (n?=?0.136–0.365 and R2?=?0.9747–0.9954). The permeation of niosomal gel was significantly enhanced across rabbit skin compared to the pure drug-derived gel. Therefore, the PNs are found promising candidates for oral as dissolution enhancement and sustained release for oral and topical delivery of pentazocine for the management of cancer pain.  相似文献   
106.
Serine racemase (SR) is an enzyme that catalyses the synthesis of d ‐serine, an endogenous coagonist for N‐methyl‐D‐aspartate (NMDA)‐type glutamate receptor in the central nervous system. Our previous study demonstrated that SR was expressed in the epidermis of wild‐type (WT) mice but not in SR knockout (KO) mice. In addition, SR immune‐reactivity was only found in the granular and cornified layers of the epidermis in WT mice. These findings suggested that SR is involved in the differentiation of epidermal keratinocytes and the formation of the skin barrier. However, its role in skin barrier dysfunction such as atopic dermatitis (AD) remains elusive. AD is a chronic inflammatory disease of skin, and the clinical presentation of AD has been reported to be occasionally associated with psychological factors. Therefore, this study examined the content of d ‐serine in stratum corneum in AD patients and healthy controls using a tape‐stripping method. Skin samples were collected from the cheek and upper arm skin of AD patient's lesion and healthy individuals. The d ‐serine content was significantly increased in the involved skin of AD in comparison with healthy individuals. An immunohistochemical analysis also revealed an increased SR expression in the epidermis of AD patients. Furthermore, the SR expression in cultured human keratinocytes was significantly increased by the stimulation with tumour necrosis factor ‐α or macrophage migration inhibitory factor. Taken together, these findings suggest that d ‐serine expressed particularly strongly in AD lesional skin and that the SR expression in the keratinocytes is linked to inflammatory cytokines.  相似文献   
107.
Phenol is a commonly found organic pollutant in industrial wastewaters. Its ecotoxicological significance is well known and, therefore, the compound is often required to be removed prior to discharge. In this study, plant-bacterial synergism was established in floating treatment wetlands (FTWs) in an attempt to maximize the removal of phenol from contaminated water. A common wetland plant, Typha domingensis, was vegetated on a floating mat and augmented with three phenol-degrading bacterial strains, Acinetobacter lwofii ACRH76, Bacillus cereus LORH97, and Pseudomonas sp. LCRH90, to develop FTWs for the remediation of water contaminated with phenol. All of the strains are known to have phenol-reducing properties, and grow well in FTWs. Results showed that T. domingensis was able to remove a small amount of phenol from the contaminated water; however, bacterial augmentation enhanced the removal potential significantly, i.e., 0.146 g/m2/day vs. 0.166 g/m2/day, respectively. Plant biomass also increased in the presence of bacterial consortia; and inoculated bacteria displayed successful colonization/survival in the rhizosphere, root interior and shoot interior of the plant. Similarly, highest reduction in chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and total organic carbon (TOC) was achieved by the combined application of plants and bacteria. The study demonstrates that the plant-bacterial synergism in a FTW may be a more effective approach for the remediation of phenol-contaminated water.  相似文献   
108.
Plasmonics - We numerically analyzed a simple and novel design of multi-broadband plasmonic absorber which consists of a planar array of thin gold square ring structures on dielectric/metal...  相似文献   
109.
Journal of Plant Growth Regulation - Chromium (Cr) is a very toxic heavy metal present in agricultural soils. Soils contaminated with Cr are the major source of Cr entrance into the food chain. The...  相似文献   
110.
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