Uncovering toxin production and molecular-level responses in Microcystis aeruginosa exposed to the flame retardant Tetrabromobisphenol A

Li Yin; Yu Yin; Lin Xu; Yong Zhang; Kaipian Shi; Juan Wang; Junfeng An; Huan He; Shaogui Yang; Lixiao Ni; Shiyin Li

doi:10.1016/j.jhazmat.2024.136886

Uncovering toxin production and molecular-level responses in Microcystis aeruginosa exposed to the flame retardant Tetrabromobisphenol A

J Hazard Mater. 2024 Dec 14:485:136886. doi: 10.1016/j.jhazmat.2024.136886. Online ahead of print.

Authors

Li Yin¹, Yu Yin¹, Lin Xu¹, Yong Zhang², Kaipian Shi¹, Juan Wang¹, Junfeng An¹, Huan He¹, Shaogui Yang¹, Lixiao Ni³, Shiyin Li⁴

Affiliations

¹ School of Environment, Nanjing Normal University, Nanjing 210023, China.
² Department of Geological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA.
³ School of Environment, Hohai University, Nanjing 210098, China; Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, Hohai University, Nanjing 210098, China.
⁴ School of Environment, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China. Electronic address: lishiyin@njnu.edu.cn.

PMID: 39689566
DOI: 10.1016/j.jhazmat.2024.136886

Abstract

Tetrabromobisphenol A (TBBPA) poses significant ecological risks owing to its toxicity; however, its specific effects on toxin-producing cyanobacteria in aquatic environments remain poorly understood. This study systematically investigated the effects of TBBPA at concentrations ranging from 100 ng/L to 100 mg/L on Microcystis aeruginosa (M. aeruginosa) by examining growth, photosynthesis, toxin production, antioxidant responses, and molecular-level changes. The results indicated that low levels of TBBPA (0.1-1000 μg/L) induced stimulatory effects on the growth and microcystin-leucine-arginine (MC-LR) production of M. aeruginosa. Metabolomic analysis revealed that low levels of TBBPA significantly upregulated metabolites associated with energy metabolism, xenobiotic biodegradation, oxidative stress responses, and protein biosynthesis in M. aeruginosa, potentially contributing to the observed hormetic effect. Conversely, higher doses (40-100 mg/L) inhibited growth and significantly increased MC-LR release by compromising cellular structural integrity. Proteomic analysis revealed that toxic levels of TBBPA significantly affected the expression of proteins associated with energy harvesting and utilization. Specifically, TBBPA disrupted electron flow in oxidative phosphorylation and the photosynthetic system (PS) by targeting PSI, PSII, and Complex I, impairing energy acquisition and causing oxidative damage, ultimately leading to algal cell death. Additionally, proteins involved in the biosynthesis and metabolism of cysteine, methionine, phenylalanine, tyrosine, and tryptophan were upregulated, potentially enhancing M. aeruginosa resistance to TBBPA-induced stress. This study offers insights into the effects of TBBPA on M. aeruginosa and its potential risks to aquatic ecosystems.

Keywords: Cyanobacteria; Microcystin; Microcystis aeruginosa; Tetrabromobisphenol-A; proteomics.