The bioremediation potentials and mercury(II)-resistant mechanisms of a novel fungus Penicillium spp. DC-F11 isolated from contaminated soil

Junjun Chang; Yu Shi; Guangzheng Si; Qingchen Yang; Jia Dong; Jinquan Chen

doi:10.1016/j.jhazmat.2020.122638

The bioremediation potentials and mercury(II)-resistant mechanisms of a novel fungus Penicillium spp. DC-F11 isolated from contaminated soil

J Hazard Mater. 2020 Sep 5:396:122638. doi: 10.1016/j.jhazmat.2020.122638. Epub 2020 Apr 7.

Authors

Junjun Chang¹, Yu Shi², Guangzheng Si², Qingchen Yang², Jia Dong³, Jinquan Chen⁴

Affiliations

¹ Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming, 650091, China; Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming, 650091, China; International Cooperative Center of Plateau Lake Ecological Restoration and Watershed Management of Yunnan, Kunming, 650091, China.
² Institute of International Rivers and Eco-security, Yunnan University, Kunming, 650091, China.
³ Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming, 650091, China.
⁴ Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming, 650091, China; Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming, 650091, China; International Cooperative Center of Plateau Lake Ecological Restoration and Watershed Management of Yunnan, Kunming, 650091, China. Electronic address: chengjinquan@ynu.edu.cn.

PMID: 32361297
DOI: 10.1016/j.jhazmat.2020.122638

Abstract

Bioremediation of Hg-contaminated soil using microbe-based strategies is a promising and efficient method as it is inexpensive and not harmful to the environment. In this study, a novel Hg(II)-volatilizing fungus Penicillium spp., DC-F11 was isolated and showed bioremediation potential for reducing Hg(II) phytotoxicity, total Hg, and exchangeable Hg in Hg(II)-polluted soil. Subsequently, the mechanisms of Hg(II) volatilization and resistance involved were investigated using multiple complementary techniques. The fungal cells could detoxify Hg(II) by extracellular sequestration via adsorption and precipitation. Moreover, a comparative transcriptome analysis uncovered the primary intracellular adaptive responses of the DC-F11 to Hg(II) stress, including mer-mediated detoxification system, thiol compound metabolism, and oxidative stress defense and damage repair metabolism. These results showed that the resistance of DC-F11 to Hg(II) was generally a multisystem collaborative process. Here, we report, for the first time, that the mer-mediated detoxification system was responsible for Hg(II) volatilization in fungus. These findings provide a better understanding of the mechanisms involved in Hg(II) volatilization and resistance that occur in fungi and also provide a strong theoretical basis for the future application of fungi in the bioremediation of Hg-polluted environments.

Keywords: Bioremediation; Fungi; Hg(II) resistance; Hg(II) volatilization; RNA-Seq.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biodegradation, Environmental
Fungi
Mercury* / toxicity
Penicillium*
Soil
Soil Pollutants* / analysis
Soil Pollutants* / toxicity

Substances

Soil
Soil Pollutants
Mercury