南湖新闻网讯(通讯员 邓波)近日,我校best365网页版登录农业生物质增值利用技术与装备团队袁巧霞教授课题组在环境学科领域知名国际学术期刊Water Research上发表了题为“Biotransformation of Pb and As from sewage sludge and food waste by black soldier fly larvae: migration mechanism of bacterial community and metalloregulatory protein scales”的研究论文。该研究借助16s rRNA和宏基因组测序技术,揭示了黑水虻无害化处理污水活性污泥过程中虫体肠道微生物群落及功能基因对重金属Pb和As迁移转化的调控机制,阐明了Pb、As重金属在虫体、虫沙中的赋存形态、演化规律及迁移转化路径,该研究成果为黑水虻无害化、资源化转化处理活性污泥提供了科学依据。
我国每年各类污水活性污泥年产生量超7000万吨,尤其是富含Pb、As等相关重金属,不仅环境风险高,而且处理难度大。黑水虻是一种生长速度快、重金属耐受性高、有机废弃物转化能力强的食腐昆虫,因其独特的生物学特性,已被成功用于污水活性污泥的无害化处理与资源化利用。但截至目前,污水活性污泥黑水虻无害化处理技术还未能大规模推广应用,其中关键性制约因素是黑水虻转化处理活性污泥过程中相关重金属的迁移转化路径及其演变钝化机制有待进一步明确。
针对这一关键问题,袁巧霞教授团队聚焦Pb和As两种典型的活性污泥重金属,设计了黑水虻重金属梯度阈值养殖试验,并借助16s rRNA和宏基因组测序技术,深入研究了Pb、As重金属在转化过程中的形态转化和迁移路径,重点解析了成熟幼虫的肠道微生物群落和金属调控蛋白的作用规律与调控机制。结果表明,黑水虻转化降低了重金属的迁移性,虫沙中的铅和砷主要是残渣态(31-51%),同时幼虫还可以将32-48%的铅和砷富集在体内。16s rRNA分析表明铅和砷胁迫降低了幼虫肠道中Firmicutes, Romboutsia和Lactobacillus的丰度(6.3-92.0%)。宏基因组测序发现在金属反应转录因子CadC的的调节下,铅胁迫刺激P型ATP酶ZntA和底物结合蛋白EfeO的表达,从而实现对铅的结合、转运和排泄。幼虫肠道中多种功能蛋白协同调节As (III)的迁移,ArsD 是一种金属伴侣,可将 As (III) 传递给 ArsA,从而提高对 As (III) 的亲和力。ArsA 结合催化 ATP 对 As (III) 的吸收,并通过砷外排系统(例如ArsB,ArsJ,ArsR和ArsK)排出砷。
best365网页版登录在读博士研究生邓波为第一作者,袁巧霞教授和曹红亮教授为共同通讯作者。本研究得到国家自然科学基金、湖北省科技创新计划等课题资助。
原文链接:https://doi.org/10.1016/j.watres.2024.121405
英文摘要:
The accumulation and transformation of lead (Pb) and arsenic (As) during the digestion of sewage sludge (SS) by black soldier fly larvae (BSFL) remain unclear. In this study, we used 16s rRNA and metagenomic sequencing techniques to investigate the correlation between the microbial community, metalloregulatory proteins (MRPs), and Pb and As migration and transformation. During the 15-day test period, BSFL were able to absorb 34–48% of Pb and 32–45% of As into their body. Changes in bacterial community abundance, upregulation of MRPs, and redundancy analysis (RDA) results confirmed that ZntA, EfeO, CadC, ArsR, ArsB, ArsD, and ArsA play major roles in the adsorption and stabilization of Pb and As, which is mainly due to the high contribution rates of Lactobacillus (48–59%) and Enterococcus (21–23%). Owing to the redox reaction, the regulation of the MRPs, and the change in pH, the Pb and As in the BSFL residue were mainly the residual fraction (F4). The RDA results showed that Lactobacillus and L. koreensis could significantly (P < 0.01) reduce the reducible fraction (F2) and F4 of Pb, whereas Firmicutes and L. fermentum can significantly (P < 0.05) promote the transformation of As to F4, thus realizing the passivation Pb and As. This study contributes to the understanding of Pb and As in SS adsorbed by BSFL and provides important insights into the factors that arise during the BSFL-mediated migration of Pb and As.
审核人:袁巧霞
来源:南湖新闻网http://news.hzau.edu.cn/2024/0306/69109.shtml