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Optimizing UVA and UVC synergy for effective control of harmful cyanobacterial blooms.

ABSTRACT: Harmful cyanobacterial blooms (HCBs) pose a global ecological threat. Ultraviolet C (UVC) irradiation at 254 nm is a promising method for controlling cyanobacterial proliferation, but the growth suppression is temporary. Resuscitation remains a challenge with UVC application, necessitating alternative strategies for lethal effects. Here, we show synergistic inhibition of Microcystis aeruginosa using ultraviolet A (UVA) pre-irradiation before UVC. We find that low-dosage UVA pre-irradiation (1.5 J cm^-2) combined with UVC (0.085 J cm^-2) reduces 85% more cell densities compared to UVC alone (0.085 J cm^-2) and triggers mazEF-mediated regulated cell death (RCD), which led to cell lysis, while high-dosage UVA pre-irradiations (7.5 and 14.7 J cm^-2) increase cell densities by 75-155%. Our oxygen evolution tests and transcriptomic analysis indicate that UVA pre-irradiation damages photosystem I (PSI) and, when combined with UVC-induced PSII damage, synergistically inhibits photosynthesis. However, higher UVA dosages activate the SOS response, facilitating the repair of UVC-induced DNA damage. This study highlights the impact of UVA pre-irradiation on UVC suppression of cyanobacteria and proposes a practical strategy for improved HCBs control.

SUBMITTER: Zhu Y

PROVIDER: S-EPMC11305005 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature

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Optimizing UVA and UVC synergy for effective control of harmful cyanobacterial blooms.

Zhu Yinjie Y Ding Jian J Wang Xiaoxiong X Wang Xuejian X Cao Huansheng H Teng Fei F Yao Shishi S Lin Zhiru Z Jiang Yuelu Y Tao Yi Y

Environmental science and ecotechnology 20240709

Harmful cyanobacterial blooms (HCBs) pose a global ecological threat. Ultraviolet C (UVC) irradiation at 254 nm is a promising method for controlling cyanobacterial proliferation, but the growth suppression is temporary. Resuscitation remains a challenge with UVC application, necessitating alternative strategies for lethal effects. Here, we show synergistic inhibition of <i>Microcystis aeruginosa</i> using ultraviolet A (UVA) pre-irradiation before UVC. We find that low-dosage UVA pre-irradiatio ...[more]

PMID: 39114557

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Optimizing UVA and UVC synergy for effective control of harmful cyanobacterial blooms.

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Optimizing UVA and UVC synergy for effective control of harmful cyanobacterial blooms.

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