One-step synthesis of ferrous disulfide and iron nitride modified hydrochar for enhanced adsorption and reduction of hexavalent chromium in Bacillus LD513 by promoting electron transfer and microbial metabolism.

Microbial immobilization technology is effective in improving bioremediation efficiency and heavy metal pollution. Herein, Bacillus LD513 with hexavalent chromium (Cr(VI)) tolerance was isolated and immobilized on a novel ferrous disulfide (FeS2)/iron nitride (FeN) modified hydrochar (Fe3-SNHC) prepared from waste straws. The prepared Fe3-SNHC-based LD513 (FeLD) significantly improves Cr(VI) adsorption and reduction by 31.4 % and 15.7 %, respectively, compared to LD513 alone. Furthermore, the FeLD composite system demonstrates efficient Cr(VI) removal efficiency and good environmental adaptability under different culture conditions. Microbial metabolism and electrochemical analysis indicate that Fe3-SNHC is an ideal carrier for protecting LD513 activity, promoting extracellular polymer secretion, and reducing oxidative stress. Additionally, the carrier serves as an electron shuttle that accelerates electron transfer and promotes Cr(VI) reduction. Overall, FeLD is an environmentally friendly biocomposite that shows good promise for reducing Cr(VI) contamination in wastewater treatment.

Leveraging a disulfidptosis-related signature to predict the prognosis and immunotherapy effectiveness of cutaneous melanoma based on machine learning.

BACKGROUND: Disulfidptosis is a recently discovered programmed cell death pathway. However, the exact molecular mechanism of disulfidptosis in cutaneous melanoma remains unclear. METHODS: In this study, clustering analysis was performed using data from public databases to construct a prognostic model, which was subsequently externally validated. The biological functions of the model genes were then investigated through various experimental techniques, including qRT-PCR, Western blotting, CCK-8 assay, wound healing assay, and Transwell assay. RESULTS: We constructed a signature using cutaneous melanoma (CM) data, which accurately predicts the overall survival (OS) of patients. The predictive value of this signature for prognosis and immune therapy response was validated using multiple external datasets. High-risk CM subgroups may exhibit decreased survival rates, alterations in the tumor microenvironment (TME), and increased tumor mutation burden. We initially verified the expression levels of five optimum disulfidptosis-related genes (ODRGs) in normal tissues and CM. The expression levels of these genes were further confirmed in HaCaT cells and three melanoma cell lines using qPCR and protein blotting analysis. HLA-DQA1 emerged as the gene with the highest regression coefficient in our risk model, highlighting its role in CM. Mechanistically, HLA-DQA1 demonstrated the ability to suppress CM cell growth, proliferation, and migration. CONCLUSION: In this study, a novel signature related to disulfidptosis was constructed, which accurately predicts the survival rate and treatment sensitivity of CM patients. Additionally, HLA-DQA1 is expected to be a feasible therapeutic target for effective clinical treatment of CM.