Transplantation of soil from organic field confers disease suppressive ability to conducive soil.

Organic agriculture is a sustainable method of farming, and confers disease-suppressing abilities to disease-conducive soils via specialized soil microbiomes. This study aimed at transforming a disease-conducive soil from a conventional field into disease-suppressive soil by inoculating soil from an organic field previously established as "disease-suppressive". The effectiveness of the transformed soil was established with the model plant wheat (Triticum aestivum) grown under natural conditions, with regard to its potential in inhibiting fungal phytopathogens, Rhizoctonia solani and Fusarium oxysporum. The conducive soil inoculated with the disease-suppressive soil performed better than the control conducive soil in terms of reduced disease severity in plants, improved soil nutrient content, increased activity of hydrolytic enzymes, and increased abundance of structural and functional microbial markers. The study demonstrates the efficacy of the soil microbiome under long-term organic agriculture in transforming disease-conducive soil into disease-suppressive soils. Such practises are simple and easy to implement, and could greatly improve the sustainability and crop yield in developing countries.

Role of Fungi in Imparting General Disease Suppressiveness in Soil from Organic Field.

Soil microbial communities are key players responsible for imparting suppressive potential to the soil against soil-borne phytopathogens. Fungi have an immense potential to inhibit soil-borne phytopathogens, but the fungal counterpart has been less explored in this context. We assessed the composition of fungal communities in soil under long-term organic and conventional farming practice, and control soil. The disease-suppressive potential of organic field was already established. A comparative analysis of the disease suppressiveness contributed by the fungal component of soil from conventional and organic farms was assessed using dual culture assays. The quantification of biocontrol markers and total fungi was done; the characterization of fungal community was carried out using ITS-based amplicon sequencing. Soil from organic field exhibited higher disease-suppressive potential than that from conventional farming, against the pathogens selected for the study. Higher levels of hydrolytic enzymes such as chitinase and cellulase, and siderophore production were observed in soil from the organic field compared to the conventional field. Differences in community composition were observed under conventional and organic farming, with soil from organic field exhibiting specific enrichment of key biocontrol fungal genera. The fungal alpha diversity was lower in soil from the organic field compared to the conventional field. Our results highlight the role of fungi in contributing to general disease-suppressive ability of the soil against phytopathogens. The identification of fungal taxa specifically associated with organic farming can aid in understanding the mechanism of disease suppression under such a practice, and can be exploited to induce general disease suppressiveness in otherwise conducive soil.

Temporal variation in bacterial community profile on patients' bedsheets in a primary healthcare unit.

Fabrics serve as fomites in spreading nosocomial infections. As a patient is in close contact with bedsheets, it is important to assess the seasonal variation in bacterial diversity on these in healthcare units. The study was conducted to characterise the bacterial diversity on patients' bedsheets across 7 months in a primary healthcare unit. Polyester-cotton blend fabric was stitched on bedsheets, and temporal dynamics of bacterial communities was assessed from May to November 2019. qPCR and amplicon sequencing of 16S rRNA gene was performed for profiling of bacterial community. Results revealed the dominance of Bacillota followed by Pseudomonadota, and Actinomycetota. A seasonal variation was observed in the bacterial load, with maximum values in June. This indicates the impact of environmental conditions on bacterial abundance and composition on fabrics in healthcare unit. The presence of priority pathogens on the patient bedsheets is a human health concern reiterating the need for season-specific laundering protocol.

Terminalia Arjuna bark extract impedes foam cell formation and promotes apoptosis in ox-LDL-stimulated macrophages by enhancing UPR-CHOP pathway.

BACKGROUND: Increased macrophage and foam cell apoptosis during early atherogenesis retards plaque progression by impeding foam cell formation, suppressing inflammation and limiting lesion cellularity. Our previous in vitro study in THP1 macrophages demonstrated that Terminalia Arjuna (TA) attenuates dual-specificity phosphatase1 (DUSP1), a key negative regulator of JNK/P38MAPK signaling cascade, the branch also implicated in the UPR (unfolded protein response)-CHOP-mediated apoptotic pathway; however this pathway has not been explored so far in the presence of TA. Therefore, we aimed to elucidate the pro-apoptotic effect of aqueous bark extract of TA (aqTAE) on macrophage and foam cells and the underlying mechanism associated with it. METHODS: THP1 cells were initially differentiated into macrophages with phorbol-12-myristate-13-acetate (PMA) (100 ng/ml) for 24 h, followed by ox-LDL (100 µg/ml) treatment for another 24 h to induce foam cell formation. Thereafter, macrophages and ox-LDL- treated cells were incubated with aqTAE (100 µg/ml) for the next 24 h. Further, Oil Red O (ORO) staining, CD36 expression profiling, apoptotic assay and transcriptional and translational expression of ER-stress markers i.e., X-box binding protein 1 (XBP1) and C/EBP homologous protein (CHOP) were performed for elucidating the potential mechanism underlying TA-induced macrophage and foam cell apoptosis. RESULTS: We demonstrated that ox-LDL treatment significantly increased lipid accumulation and upregulated CD36 expression, indicating foam cell formation; while the addition of aqTAE resulted in a significant decline in ORO positive cells, and suppression of CD36 expression in ox-LDL-stimulated macrophages, suggestive of reduced formation of lipid-laden foam cells. Further, aqTAE treatment alone and in combination with oxidized low-density lipoprotein (ox-LDL) stimulus, significantly attenuated CD36 expression; increased apoptosis; and augmented the expression of UPR regulatory proteins including XBP1 and CHOP, and similar observations were noted when cells were treated with ox-LDL alone. These findings indicate that TA promotes macrophage and foam cell apoptosis via enhancing UPR-mediated activation of JNK/p38MAPK-CHOP pathway in a DUSP1-dependent manner, implying a possible interplay between ox-LDL-induced ER stress- and TA-mediated MAPK signaling. CONCLUSION: Our data shows that aqTAE inhibits foam cell formation, as well as promotes macrophage and foam cell apoptosis by augmenting UPR- JNK/p38MAPK-CHOP signaling cascade via inhibiting DUSP1. These findings provide novel mechanistic insight into the anti-atherogenic potential of TA, which may prove beneficial against early-stage atherosclerotic lesions.

Complete Genome Sequence of Pseudomonas sp. Strain SK, Isolated from Organic Wheat Rhizosphere.

Here, we report the annotated whole-genome sequence of Pseudomonas sp. strain SK, isolated in India from organic wheat rhizosphere. This strain has proved to be a species with potential biocontrol activity against soilborne plant pathogens based on antiSMASH analysis.