Zhao Yanfang, Yang Jing, Wu Yuqing, Huang Baojian, Xu Lubin, Yang Jianming, Liang Bo, Han Lei
College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, 700 Changcheng Road, Qingdao 266109, Shandong, China.
Shandong Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, 700 Changcheng Road, Qingdao 266109, China.
J Hazard Mater. 2023 Jun 15;452:131265. doi: 10.1016/j.jhazmat.2023.131265. Epub 2023 Mar 23.
Although bacterial laccase (BLac) has many advantages including short fermentation period and adaptable activity to wide temperature and pH ranges, it is of challenge and significance to apply BLac to the biosensors, due to the intracellular secretion and poor electron transfer efficiency of BLac. Here, cell surface-displayed BLac (CSDBLac) was successfully constructed as whole-cell biocatalyst through microbial surface display technology, eliminating the mass transfer restriction and laborious purification steps. Meanwhile, MXenes/polyetherimide-multiwalled carbon nanotubes (MXenes/PEI-MWCNTs) nanohybrids were designed to immobilize CSDBLac and improve their electrochemical activity. Then, an electrochemical biosensor was successfully constructed to detect common phenolic pollutants (catechol and hydroquinone) by the co-immobilization of CSDBLac and MXenes/PEI-MWCNTs nanohybrids onto a glassy carbon electrode. Subsequently, it was successfully applied to the water samples assay with good reliability and repeatability. This work innovatively used BLac and nanohybrid as the core elements of biosensor, which not only effectively solved the application bottleneck of BLac on biosensors, but also dramatically promote the electro transfer efficiency between whole-cell biocatalyst and electrode. This method is of profound meanings for significantly improving the performance of phenolic biosensors and other biosensors from the origin.
尽管细菌漆酶（BLac）具有许多优点，包括发酵周期短以及对温度和pH范围的适应性强，但由于BLac的细胞内分泌和较差的电子转移效率，将其应用于生物传感器具有挑战性且意义重大。在此，通过微生物表面展示技术成功构建了细胞表面展示的BLac（CSDBLac）作为全细胞生物催化剂，消除了传质限制和繁琐的纯化步骤。同时，设计了MXenes/聚醚酰亚胺-多壁碳纳米管（MXenes/PEI-MWCNTs）纳米杂化物来固定CSDBLac并提高其电化学活性。然后，通过将CSDBLac和MXenes/PEI-MWCNTs纳米杂化物共固定在玻碳电极上，成功构建了一种电化学传感器来检测常见的酚类污染物（邻苯二酚和对苯二酚）。随后，它成功应用于水样分析，具有良好的可靠性和重复性。这项工作创新性地将BLac和纳米杂化物用作生物传感器的核心元件，不仅有效解决了BLac在生物传感器上的应用瓶颈，还显著提高了全细胞生物催化剂与电极之间的电子转移效率。该方法对于从根本上显著提高酚类生物传感器和其他生物传感器的性能具有深远意义。
