Shabaan Amany M, Embaby Marwa S, Reyad Amany M
Chemistry Department, Biochemistry division, Faculty of Science, Fayoum University, Fayoum, Egypt.
Botany Department, Faculty of Science, Fayoum University, Fayoum, Egypt.
Sci Rep. 2025 Mar 21;15(1):9774. doi: 10.1038/s41598-025-91961-6.
This study identified one bacterial isolate as Staphylococcus devriesei, which is resistant to cadmium (Cd), manganese (Mn), and chromium (Cr) using 16S rRNA gene sequencing. Following that, the strain sequence was submitted to GenBank under accession number PQ013181. In this investigation, the biosorption potential of Staphylococcus devriesei was evaluated for the biosorption of chrmoium, cadmium, and manganese ions. The effects of pH, contact time, and initial concentration were examined in a batch-mode study. According to our findings, after 6 h at the ideal pH, Staphylococcus devriesei's maximal biosorption capabilities of Cr and Cd were 98 and 81.2%, respectively. The maximum biosorption of Mn was 95.6% after 24 h at pH 6. SEM micrographs showed that, Staphylococcus devriesei were irregular and cracked with wrinkles on the surface after absorbing the studied Cr metal ions. It was observed that the alterations in cell size occurred when the bacterium was exposed to a dose of Mn and the aggregation of cells was seen. Bacterial cells treated with Cd exhibited irregularities, featuring depressions on their surfaces, and surface wrinkles. FTIR analysis showed obvious alterations in peak positions and intensities before and after the biosorption process. Energy dispersive X-ray analysis showed extra metal depositions on the treated cell surface compared to the control. At the ultrastructural level, TEM imaging demonstrates the involvement of extracellular and intracellular precipitates and accumulated metals on the cell walls. Thus, the results of this study indicated that Staphylococcus devriesei can effectively aid in the remediation of contaminated water with moderate to light levels of Cd, Cr, and Mn.
本研究通过16S rRNA基因测序鉴定出一株细菌为德弗里斯葡萄球菌，该菌对镉（Cd）、锰（Mn）和铬（Cr）具有抗性。随后，该菌株序列已提交至GenBank，登录号为PQ013181。在本研究中，评估了德弗里斯葡萄球菌对铬、镉和锰离子的生物吸附潜力。在批次模式研究中考察了pH值、接触时间和初始浓度的影响。根据我们的研究结果，在理想pH值下6小时后，德弗里斯葡萄球菌对Cr和Cd的最大生物吸附能力分别为98%和81.2%。在pH值为6的条件下24小时后，Mn的最大生物吸附率为95.6%。扫描电子显微镜图像显示，德弗里斯葡萄球菌在吸收所研究的Cr金属离子后表面不规则且有裂纹和皱纹。观察到当细菌暴露于一定剂量的Mn时细胞大小发生改变，并且出现了细胞聚集现象。用Cd处理的细菌细胞表现出不规则性，其表面有凹陷和表面皱纹。傅里叶变换红外光谱分析表明，生物吸附过程前后峰位和强度有明显变化。能量色散X射线分析表明，与对照相比，处理后的细胞表面有额外的金属沉积。在超微结构水平上，透射电子显微镜成像显示细胞外和细胞内沉淀物以及细胞壁上积累的金属的参与。因此，本研究结果表明，德弗里斯葡萄球菌可以有效地辅助修复中度至轻度Cd、Cr和Mn污染的水。
