Does temperature favour the spread of Raphidiopsis raciborskii, an invasive bloom-forming cyanobacterium, by altering cellular trade-offs?

Baohai Zheng; Shuhan He; Lu Zhao; Jiaxin Li; Yuxin Du; Yuxin Li; Junqiong Shi; Zhongxing Wu

doi:10.1016/j.hal.2023.102406

Does temperature favour the spread of Raphidiopsis raciborskii, an invasive bloom-forming cyanobacterium, by altering cellular trade-offs?

Harmful Algae. 2023 May:124:102406. doi: 10.1016/j.hal.2023.102406. Epub 2023 Feb 18.

Authors

Baohai Zheng¹, Shuhan He¹, Lu Zhao¹, Jiaxin Li¹, Yuxin Du¹, Yuxin Li¹, Junqiong Shi¹, Zhongxing Wu²

Affiliations

¹ Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China.
² Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China. Electronic address: wuzhx@swu.edu.cn.

PMID: 37164561
DOI: 10.1016/j.hal.2023.102406

Abstract

As a tropical filamentous cyanobacterium, Raphidiopsis raciborskii has attracted much attention due to its expansion and toxin production. However, the mechanisms of its expansion to temperate regions have not been studied in detail. To address the potential strategies, the physiological and metabolomic profiles of R. raciborskii FACHB 1096 isolated from a temperate lake in China were determined and measured at different temperatures (10 °C, 15 °C, 20 °C, 25 °C, and 32 °C). The results demonstrated that temperature significantly changed cell viability, chlorophyll a content, specific growth rate, Chl a fluorescence, and filamentous shape of R. raciborskii. Low temperature decreased cell viability, specific growth rate, and photosynthetic efficiency, while the proportion of akinete and carbon fixation per unit cell were significantly increased compared with high temperature (32 °C). A constructed unimodal model indicated that filament length, cell volume, and cell length/width of R. raciborskii were significantly reduced in both high and low temperature environments. Under low-temperature conditions, R. raciborskii suffered different degrees of oxidative damage and produced corresponding antioxidant substances to resist oxidative stress, suggesting that low temperature changes the metabolic level of the cells, causing the cells to gradually switch from development to defense. Metabolomic data further confirmed that temperature change induced shifts in metabolic pathways in R. raciborskii, including starch and sucrose metabolic pathways, glutathione metabolic pathways, and the pentose phosphate pathways (PPP), as well as metabolic pathways related to the tricarboxylic acid (TCA) cycle. Our results indicated that the trade-offs of R. raciborskii cells among the growth, cell size, and metabolites can be significantly regulated by temperature, with broad implications for its global expansion in temperate waterbodies.

Keywords: Invasion; Metabolomics; Raphidiopsis raciborskii; Temperature; Trade-offs.

Publication types

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

MeSH terms

Chlorophyll A / metabolism
Cyanobacteria* / physiology
Cylindrospermopsis*
Temperature

Substances

Chlorophyll A

Supplementary concepts

Cylindrospermopsis raciborskii