Discovery of a High-Efficient Algicidal Bacterium against Microcystis aeruginosa Based on Examinations toward Culture Strains and Natural Bloom Samples

He Zhang; Yan Xie; Rongzhen Zhang; Zhongliang Zhang; Xinglong Hu; Yao Cheng; Ruozhen Geng; Zengling Ma; Renhui Li

doi:10.3390/toxins15030220

Discovery of a High-Efficient Algicidal Bacterium against Microcystis aeruginosa Based on Examinations toward Culture Strains and Natural Bloom Samples

Toxins (Basel). 2023 Mar 14;15(3):220. doi: 10.3390/toxins15030220.

Authors

He Zhang^{1

2}, Yan Xie¹, Rongzhen Zhang³, Zhongliang Zhang¹, Xinglong Hu¹, Yao Cheng¹, Ruozhen Geng¹, Zengling Ma¹, Renhui Li^{1

4}

Affiliations

¹ Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection, National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, College of Life and Environmental Sciences, Wenzhou University, Wenzhou 325035, China.
² State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China.
³ Wenzhou Shanxi Hydro-junction Management Center, Wenzhou 325035, China.
⁴ Institute for Eco-Environmental Research of Sanyang Wetland, Wenzhou University, Wenzhou 325035, China.

Abstract

Harmful cyanobacterial blooms occur worldwide and pose a great threat to aquatic ecosystems and public health. The application of algicidal bacteria represents an eco-friendly strategy for controlling harmful cyanobacterial blooms; thus, searching for a high efficiency of algicidal bacteria has been becoming an important and continuous task in science. Herein, we identified a bacterial strain coded Streptomyces sp. HY with a highly algicidal activity, and investigated its algicidal efficiency and mechanism against Microcystis aeruginosa. The strain HY displayed high algicidal activity toward Microcystis aeruginosa cells, with a removal rate of 93.04% within 2 days via indirect attack. Streptomyces sp. HY also showed the ability to lyse several genera of cyanobacterial strains, including Dolichospermum, Pseudanabaena, Anabaena, and Synechocystis, whereas it showed a minor impact on the green alga Scenedesmus obliquus, demonstrating its selectivity specially for targeting cyanobacteria. Its algicidal mechanism involved damages to the photosynthesis system, morphological injury of algal cells, oxidative stress, and dysfunction of the DNA repair system. Furthermore, HY treatment reduced the expression levels of genes (mcyB and mcyD) related to microcystin biosynthesis and decreased the total content of microcystin-leucine-arginine by 79.18%. Collectively, these findings suggested that the algicidal bacteria HY is a promising candidate for harmful cyanobacterial bloom control.

Keywords: Microcystis aeruginosa; Streptomyces; algicidal bacteria; harmful cyanobacterial blooms; microcystins.

Publication types

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

MeSH terms

Ecosystem
Harmful Algal Bloom
Microcystins* / metabolism
Microcystis* / metabolism
Photosynthesis

Substances

Microcystins

Grants and funding

This study was supported by the Zhejiang Provincial Natural Science Foundation of China (No. LD21C030001), Key Research and Development Program of National Natural Science Foundation of China (Grant No. 2021YFE0112000), and National Natural Science Foundation of China (Grant No. 31970219) to R.L. Open Funding Project of the State Key Laboratory of Biocatalysis and Enzyme Engineering, (Grant No. SKLBEE2021006) to H.Z.