Department of Biotechnology and Food Engineering, Technion - Israel Institute of Technology, Haifa 3200003, Israel; Environmental Science and Engineering Program, Guangdong Technion - Israel Institute of Technology, Shantou 515063, China.
Department of Biotechnology and Food Engineering, Technion - Israel Institute of Technology, Haifa 3200003, Israel.
Microbiol Res. 2022 Dec;265:127208. doi: 10.1016/j.micres.2022.127208. Epub 2022 Sep 21.
Microbially induced carbonate precipitation (MICP) is a biomineralization process that has various applications in environmental pollution remediation and restoration of a range of building materials. In this study, a ureolytic bacterium, Lysinibacillus sp. GY3, isolated from an E-waste site, was found as a promising catalyst for remediation of heavy metals via the MICP process. This bacterial isolate produced significant amounts of urease and showed a great persistence in immobilization of potentially toxic elements. A reference ureolytic strain, Bacillus megaterium VS1, was selected in order to compare the efficiency of Lysinibacillus sp. GY3. Study on urease localization indicated 80 % more urease activity secreted extracellularly as for Lysinibacillus sp. GY3 compared to B. megaterium VS1. From the investigation on effects of metals on both intra- and extra-cellular urease, it was clear that Lysinibacillus sp. GY3 produced the most stable urease under conditions of metal pressure, especially retaining more than 70 % activity in the presence of 1 g/L Pb and Zn. These results suggest that this isolated microorganism could be promisingly introduced in the MICP process to stabilize complex heavy metal pollutions, with reference to the regulating ability under harsh conditions to stabilize urease activity. This species is so important both for its biological features and environmental impacts. In addition, the present study will bring new insight in the field of metal remediation coupled with enzyme engineered biotechnology.
微生物诱导碳酸钙沉淀（MICP）是一种生物矿化过程，在环境污染修复和一系列建筑材料的恢复中具有多种应用。在这项研究中，从电子废物场分离出的脲酶细菌Lysinibacillus sp. GY3 被发现是一种很有前途的通过 MICP 过程修复重金属的催化剂。这种细菌分离株产生了大量的脲酶，并在固定潜在有毒元素方面表现出很强的持久性。选择了参考脲酶菌株 Bacillus megaterium VS1，以便比较 Lysinibacillus sp. GY3 的效率。对脲酶定位的研究表明，与 B. megaterium VS1 相比，Lysinibacillus sp. GY3 有 80%更多的脲酶分泌到细胞外。从金属对细胞内和细胞外脲酶的影响研究中可以清楚地看出，在金属压力条件下，Lysinibacillus sp. GY3 产生的脲酶最稳定，特别是在存在 1 g/L Pb 和 Zn 的情况下，仍保留了超过 70%的活性。这些结果表明，这种分离的微生物可以在 MICP 过程中被引入，以稳定复杂的重金属污染，参考在恶劣条件下稳定脲酶活性的调节能力。该物种因其生物特征和环境影响而非常重要。此外，本研究将为金属修复领域带来新的认识，同时结合酶工程生物技术。
