Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, China.
Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA.
Bioresour Technol. 2022 Jul;355:127286. doi: 10.1016/j.biortech.2022.127286. Epub 2022 May 8.
Although biological treatment of marine aquaculture wastewater is promising, the fundamental principles driving the adsorption of tetracycline to microbial cell membrane are not well understood. Using a combination of experiments and molecular dynamics (MD) simulations, the mechanism underlying the biological removal of tetracycline from seawater was investigated. More than 90% tetracycline removal was achieved in an aerobic granular sludge system, with degradation accounting for 30% of total removal. A model of the tetracycline-dipalmitoylphosphatidylcholine lipid bilayers was established to elucidate the transport mechanism of tetracycline from bulk solution to microorganisms' cell membrane. 62% of the driving force for tetracycline adsorption on the cell membrane originated from electrostatic attraction. The electrophilic groups on tetracycline (amino and aromatic groups) were attracted to the phosphate groups in the cell membrane. Sodium ions, which are abundant in seawater, decreased the interaction energy between tetracycline and the cell membrane.
尽管生物处理海水养殖废水具有广阔的前景，但对于四环素吸附到微生物细胞膜的基本原理还了解甚少。本研究采用实验与分子动力学（MD）模拟相结合的方法，研究了海水中四环素的生物去除机制。在好氧颗粒污泥系统中，四环素的去除率超过 90%，其中降解作用占总去除量的 30%。建立了四环素-二棕榈酰磷脂酰胆碱脂质双层模型，以阐明四环素从主体溶液向微生物细胞膜的传输机制。细胞膜上四环素吸附的驱动力有 62%来自于静电吸引。四环素上的亲电基团（氨基和芳基）被细胞膜上的磷酸基团所吸引。海水中大量存在的钠离子降低了四环素与细胞膜之间的相互作用能。
