Rhizosphere Metagenomics of Paspalum scrobiculatum L. (Kodo Millet) Reveals Rhizobiome Multifunctionalities.

Multifunctionalities linked with the microbial communities associated with the millet crop rhizosphere has remained unexplored. In this study, we are analyzing microbial communities inhabiting rhizosphere of kodo millet and their associated functions and its impact over plant growth and survival. Metagenomics of Paspalum scrobiculatum L.(kodo millet) rhizopshere revealed taxonomic communities with functional capabilities linked to support growth and development of the plants under nutrient-deprived, semi-arid and dry biotic conditions. Among 65 taxonomically diverse phyla identified in the rhizobiome, Actinobacteria were the most abundant followed by the Proteobacteria. Functions identified for different genes/proteins led to revelations that multifunctional rhizobiome performs several metabolic functions including carbon fixation, nitrogen, phosphorus, sulfur, iron and aromatic compound metabolism, stress response, secondary metabolite synthesis and virulence, disease, and defense. Abundance of genes linked with N, P, S, Fe and aromatic compound metabolism and phytohormone synthesis-along with other prominent functions-clearly justifies growth, development, and survival of the plants under nutrient deprived dry environment conditions. The dominance of actinobacteria, the known antibiotic producing communities shows that the kodo rhizobiome possesses metabolic capabilities to defend themselves against biotic stresses. The study opens avenues to revisit multi-functionalities of the crop rhizosphere for establishing link between taxonomic abundance and targeted functions that help plant growth and development in stressed and nutrient deprived soil conditions. It further helps in understanding the role of rhizosphere microbiome in adaptation and survival of plants in harsh abiotic conditions.

Bacterial diversity in rhizosphere of Paspalum scrobiculatum L. (kodo millet) is revealed with shotgun metagenome sequencing and data analysis.

Rhizosphere bacterial communities of kodo millet plant was analyzed from a large metagenome sequence dataset. Plant rhizosphere samples of kodo millet was collected in replicates and the metagenomic sequence data were obtained through shotgun sequencing. Overall sequences in the dataset were 476,649 comprising total read length of 179,349,372 base pairs. Taxonomic data analysis led to characterize α-diversity of 107 species. Dominance of actinobacteria followed by unclassified sequences (derived from Bacteria) was recorded. Raw data along with the analysis result is publicly available from the MG-RAST server with ID mgm4761530.3.

Metatranscriptome Analysis Deciphers Multifunctional Genes and Enzymes Linked With the Degradation of Aromatic Compounds and Pesticides in the Wheat Rhizosphere.

Agricultural soils are becoming contaminated with synthetic chemicals like polyaromatic compounds, petroleum hydrocarbons, polychlorinated biphenyls (PCBs), phenols, herbicides, insecticides and fungicides due to excessive dependency of crop production systems on the chemical inputs. Microbial degradation of organic pollutants in the agricultural soils is a continuous process due to the metabolic multifunctionalities and enzymatic capabilities of the soil associated communities. The plant rhizosphere with its complex microbial inhabitants and their multiple functions, is amongst the most live and dynamic component of agricultural soils. We analyzed the metatranscriptome data of 20 wheat rhizosphere samples to decipher the taxonomic microbial communities and their multifunctionalities linked with the degradation of organic soil contaminants. The analysis revealed a total of 21 different metabolic pathways for the degradation of aromatic compounds and 06 for the xenobiotics degradation. Taxonomic annotation of wheat rhizosphere revealed bacteria, especially the Proteobacteria, actinobacteria, firmicutes, bacteroidetes, and cyanobacteria, which are shown to be linked with the degradation of aromatic compounds as the dominant communities. Abundance of the transcripts related to the degradation of aromatic amin compounds, carbazoles, benzoates, naphthalene, ketoadipate pathway, phenols, biphenyls and xenobiotics indicated abundant degradation capabilities in the soils. The results highlighted a potentially dominant role of crop rhizosphere associated microbial communities in the remediation of contaminant aromatic compounds.

Disruption of Skin Stem Cell Homeostasis following Transplacental Arsenicosis; Alleviation by Combined Intake of Selenium and Curcumin.

Of late, a consirable interest has grown in literature on early development of arsenicosis and untimely death in humans after exposure to iAs in drinking water in utero or during the childhood. The mechanism of this kind of intrauterine arsenic poisoning is not known; however it is often suggested to involve stem cells. We looked into this possibility by investigating in mice the influence of chronic in utero exposure to arsenical drinking water preliminarily on multipotent adult stem cell and progenitor cell counts at the beginning of neonatal age. We found that repeated intake of 42.5 or 85 ppm iAs in drinking water by pregnant BALB/c mice substantially changed the counts of EpASCs, the progenitor cells, and the differentiated cells in epidermis of their zero day old neonates. EpASCs counts decreased considerably and the differentiated/apoptosed cell counts increased extensively whereas the counts of progenitor cell displayed a biphasic effect. The observed trend of response was dose-dependent and statistically significant. These observations signified a disruption in stem cell homeostasis. The disorder was in parallel with changes in expression of biomarkers of stem cell and progenitor (TA) cell besides changes in expression of pro-inflammatory and antioxidant molecules namely Nrf2, NFkB, TNF-α, and GSH. The biological monitoring of exposure to iAs and the ensuing transplacental toxicity was verifiable correspondingly by the increase in iAs burden in hair, kidney, skin, liver of nulliparous female mice and the onset of chromosomal aberrations in neonate bone marrow cells. The combined intake of selenite and curcumin in utero was found to prevent the disruption of homeostasis and associated biochemical changes to a great extent. The mechanism of prevention seemed possibly to involve (a) curcumin and Keap-1 interaction, (b) consequent escalated de novo GSH biosynthesis, and (c) the resultant toxicant disposition. These observations are important with respect to the development of vulnerability to arsenicosis and other morbidities later in life after repeated in utero or postnatal exposure to iAs in drinking water that may occur speculatively through impairment of adult stem cell dependent innate tissue repair mechanism.

Mammalian cell-transforming potential of traffic-linked ultrafine particulate matter PM0.056 in urban roadside atmosphere.

We examined the clastogenic and cell-transforming potential of ultrafine particulate matter fraction PM0.056 of urban ambient aerosol using mammalian cells. PM1.0, PM0.56 and PM0.056 fractions were sampled from roadside atmosphere of an urban area using the cascade impactor MOUDI-NR-110. The potential to induce cytotoxicity, DNA damage and micronuclei formation was examined at the test concentrations of 3, 6, 12.5, 25, 50 and 100 µg/ml using the 3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, the plasmid relaxation assay and the C3H10T1/2 (10T1/2) cells. The cell-transforming potential was investigated in vitro using 10T1/2 cell transformation assay and the soft agar assay. PM1, PM0.56 and PM0.056 fractions were found to be toxic in dose-dependent manner. These induced cytotoxicity at five test concentrations, the ultrafine particle fraction PM0.056 showed greater cytotoxic potential. PM0.056 induced micronucleus formation in 10T1/2 cells. The effect was statistically significant. The DNA-damaging potential was measured in a plasmid relaxation assay. Both fine and ultrafine particle fraction PM0.56 and PM0.056 displayed greater effect as compared to larger PM1 fraction. DNA damage was found to be dependent on particulate matter intrinsic pro-oxidant chemicals. The ability of the ultrafine particle fraction PM0.056 to induce morphological cell transformation was demonstrated by significant and dose-dependent increases in type III focus formation by morphologically transformed cells in culture flasks and their clonal expansion in soft agar. It is concluded that the traffic-linked ultrafine particle fraction PM0.056 in the atmosphere by the roadside of an urban area is clastogenic and able to induce morphological transformation of mammalian cells.

Rapid isolation of integrin rich multipotent stem cell pool and reconstruction of mouse epidermis equivalent.

We describe here epidermis reconstruction using multipotent mouse epidermal stem cells (EpSCs) enriched from keratinocyte isolates exploting exclusively the stem cell-adhesive property. This method excluded flowcytometry and was swift. Percent enrichment was measured by the uptake of Propidium iodide and Hoechst-33342 dye using flowcytometry to determine EpSCs yield. The sorted cells were characterized by analysis of stem cell markers using immunocytochemistry and immunoblotting techniques. Epidermis was reconstructed using the identified seeding density of EpSCs and the airlift tissue culture. Histology of natural vs reconstructed mammalian epidermis was also compared. Results showed a radical improvement of near 99% in the yield of integrin overexpressing EpSCs. The enriched EpSCs tested positive for biomarkers namely cytokeratin K-15 and, K-14, p63, beta-1-integrin, CD34 and could be passaged for longer durations. Adhesion sorted cells reconstructed the epidermis. The process of tissue reconstruction was faster using the adhesion sorted cells than the FACS sorted EpSCs. The product bioengineered using multipotent EpSCs was histologically similar to normal epidermis. Features like strata basalae, spinosum, granulosum, and corneum were alike real epidermis. The reconstructed epidermis displayed normal homeostasis, which can be considered an approximating actual product for investigative dermatology, toxicology, therapeutic research, regenerative medicine, and tissue engineering.

Ultrafine particles in urban ambient air and their health perspectives.

Ultrafine particles (UfPs, PM<0.1) are constituents of urban ambient air aerosol. We have reviewed literature on UfPs in urban ambient air and their health perspectives. Generally traffic-linked and of anthropogenic origin, these are toxicants and a health risk factor for urban subjects. UfPs occur in single and agglomerate forms. Studies on the number concentrations of UfPs show tens of thousand times greater levels in urban aerosol than in nonurban aerosol. These nanosize pollutants seem to have more aggressive implications than other respirable fractions of urban aerosol. In literature, it is hypothesized that a chronic exposure to their high number concentrations and their vast surface area, transporting various toxicants, injure tissues or cells and induce inflammation or, eventually, adverse health effects. UfPs are deposited deep in the tissues, translocate, and skip the innate clearance mechanisms. After retention for a long time, these can infiltrate into the interstitium and permeate cells. Traffic-linked UfPs have been found to be toxic to the respiratory, cardiovascular, and nervous systems. At the molecular level, UfPs influence signaling cascade, actin-cytoskeleton pathway, immunoregulation, reactive oxygen species generation to trigger histaminic response, mast cell activation, and pro-inflammatory changes; their mutagenic and carcinogenic effects are also tacit in view of the carcinogenic potential of diesel exhaust in humans. The molecular changes are proposed to be the subclinical effects that manifest disease exacerbations or the predisposition of subjects to pathologies after exposure to UfP. A legislatively regulated monitoring of UfP-contaminated urban ambient air environment is also endorsed to reduce the disease load or its exacerbation that is growing in diesel exhaust (a human carcinogen)-polluted urban areas.

Single wall carbon nanotubes block ion passage in mechano-sensitive ion channels by interacting with extracellular domain.

Mechanosensitive ion channel transduce physical stresses to cells by the response of electro-chemicals exchange. The purpose of this study was to improve understanding of ion channel inhibition process by SWCNTs. PatchDock and FireDock results suggest that the SWCNTs interact with the extracellular domain of the ion channels. SWCNTs can be considered as the new class of ion channel inhibitors.