Effect of humic acid on degradation of PTBP by strain Tas13

Institute of Environmental Health and Ecological Security, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, P. R. China

^* Corresponding Author, zh10040903@163.com

Abstract

p-tert-Butylphenol (PTBP) is a kind of alkylphenol endocrine disruptor. PTBP is not only toxic to aquatic organisms and animals because of its high persistence in the environment, but also has acute toxicity, chronic toxicity, endocrine interference and certain toxicity of reproductive development. It is also harmful to human health and has become an important environmental pollutant. Therefore, the pollution of PTBP and its removal have attracted wide attention. Humic acid affects its adsorption and biodegradation efficiency in water environment. In this study, the adsorption analysis of PTBP by humic acid and the mechanism of the effect of humic acid on the degradation of PTBP by Tas13 were investigated. The results showed that humic acid could adsorb PTBP and promote the degradation of PTBP by Tas13.Raman spectroscopy suggests that humic acid may be associated with relaxation of membrane proteins and lipid monolayers to promote subsequent intracellular metabolism. Zeta potential analysis showed that humic acid interacts with bacterial surface functional groups to generate and regulate the transmembrane transport of carboxyl, amino and hydroxyl groups. The addition of humic acid promotes the transport of PTBP from the outside to the inside of bacterial cells, thus effectively degrading it. In addition, by measuring the C23O activity of strain Tas13, humic acid stimulated the active C23O gene, which enhanced the expression of C23O gene mediated by strain Tas13.