Characteristics and bacterial community dynamics during extracellular polymeric substance (EPS) degradation of cyanobacterial blooms

Ye, Tianran; Zhao, Zhen; Bai, Leilei; Song, Na; Jiang, Haipeng

doi:10.1016/j.scitotenv.2020.142309

Cited by 30 publications

(10 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…could be considered as the response of an adaptive mechanism to avoid acute cell damage and the harmful effects of long‐term UV radiation exposure (Xu et al, 2013). In addition to their protective function, changes of organic components in external layers could cause variations of the surrounding microbial community composition and diversity (Ye et al, 2020). Therefore, it might further affect the ecological function of the whole ecosystem.…”

Section: Discussionmentioning

confidence: 99%

Insights into the role of external layers in cyanobacteria at varying temperatures and their regulatory mechanism

Cheng

Yan

et al. 2022

Freshwater Biology

View full text Add to dashboard Cite

The dominance of cyanobacteria and their adaptability to changing climates might be attributed to their morphological plasticity related to external layers. The content of exopolysaccharides in cyanobacterial external layers has been shown to increase at elevated temperatures. However, the answers to the questions of why and how cyanobacteria adapt to varying temperatures by adjusting the physiological and biophysical properties of their external layers are still not clear. We cultivated three cyanobacterial strains, Nostoc sp. FACHB‐2009, Dolichospermum sp. FACHB‐82 and Microcystis sp. FACHB‐3296, which are embedded in three typical types of external layers—sheath, capsule and slime, respectively––and each grown at three different temperatures (10°C, 25°C and 35°C). The results showed that varying the temperature significantly changed the physicochemical properties of the external layers. High temperature conditions promoted increases in colony sizes compared to the control, with the external layers becoming thicker, looser and more adhesive, whereas cell sizes did not significantly change. Additionally, the expression patterns of related genes varied with temperature; it represents several temp dependent genes related to synthesis of nucleotide sugars were upregulated at high temperature but downregulated at low temperature. As the external layers are wrapped outside cells, we assumed a “spherical shell heat conduction model”. Through that, we inferred that the presence of external layers influenced heat transfer in the cyanobacteria, thereby playing a role in stabilising cell activity at various temperatures. Transcriptome tests showed that the use of intracellularly stored nucleotide sugars for external layer synthesis was the preferred process for cyanobacteria at low temperature, whereas de novo external layer synthesis was the preferred process for cyanobacteria at high temperature.

show abstract

Section: Discussionmentioning

confidence: 99%

Insights into the role of external layers in cyanobacteria at varying temperatures and their regulatory mechanism

Cheng

Yan

et al. 2022

Freshwater Biology

View full text Add to dashboard Cite

show abstract

“…On the contrary, because of these self-ameliorative processes by phytoplankton, heteroaggregation and sinking of MP and phytoplankton may eventually lower primary productivity and displace MP from surface waters to subsurface waters and sediments. ,, Likewise, the increased synthesis of EPS signifies the release of photosynthetically fixed DOC which could be otherwise used by organisms for cell division and growth. For example, the increased DOC release may also attract and amend the innate phycosphere bacterial community of the phytoplankton. ,, These self-ameliorative processes are defined by environmental factors, and thus may not keep pace with the burgeoning plastic input. Consequently, further comprehensive studies on various defense and ameliorative mechanisms of phytoplankton toward MP, PL, and associated pollutants are needed to shed light on the eventual fate and transport of MP, and phytoplankton, and their cumulative impact on biogeochemical cycling.…”

Section: Can Aquatic Ecosystems Bear This Lethal Burden On Primary Pr...mentioning

confidence: 99%

Gross Negligence: Impacts of Microplastics and Plastic Leachates on Phytoplankton Community and Ecosystem Dynamics

Amaneesh

Balan

Silpa

et al. 2022

Environ. Sci. Technol.

View full text Add to dashboard Cite

Plastic debris is an established environmental menace affecting aquatic systems globally. Recently, microplastics (MP) and plastic leachates (PL) have been detected in vital human organs, the vascular system, and in vitro animal studies positing severe health hazards. MP and PL have been found in every conceivable aquatic ecosystem�from open oceans and deep sea floors to supposedly pristine glacier lakes and snow covered mountain catchment sites. Many studies have documented the MP and PL impacts on a variety of aquatic organisms, whereby some exclusively focus on aquatic microorganisms. Yet, the specific MP and PL impacts on primary producers have not been systematically analyzed. Therefore, this review focuses on the threats posed by MP, PL, and associated chemicals on phytoplankton, their comprehensive impacts at organismal, community, and ecosystem scales, and their endogenous amelioration. Studies on MP-and PL-impacted individual phytoplankton species reveal the production of reactive oxygen species, lipid peroxidation, physical damage of thylakoids, and other physiological and metabolic changes, followed by homo-and heteroaggregations, ultimately eventuating in decreased photosynthesis and primary productivity. Likewise, analyses of the microbial community in the plastisphere show a radically different profile compared to the surrounding planktonic diversity. The plastisphere also enriches multidrug-resistant bacteria, cyanotoxins, and pollutants, accelerating microbial succession, changing the microbiome, and thus, affecting phytoplankton diversity and evolution. These impacts on cellular and community scales manifest in changed ecosystem dynamics with widespread bottom-up and top-down effects on aquatic biodiversity and food web interactions. These adverse effects�through altered nutrient cycling�have "knock-on" impacts on biogeochemical cycles and greenhouse gases. Consequently, these impacts affect provisioning and regulating ecosystem services. Our citation network analyses (CNA) further demonstrate dire effects of MP and PL on all trophic levels, thereby unsettling ecosystem stability and services. CNA points to several emerging nodes indicating combined toxicity of MP, PL, and their associated hazards on phytoplankton. Taken together, our study shows that ecotoxicity of plastic particles and their leachates have placed primary producers and some aquatic ecosystems in peril.

show abstract

“…The speci c properties of cyanobacterial extracellular polymeric substance is that it contains two different uronic acids, sulphate groups and monosaccharides with a high number of different groups [17]. Several studies have been reported on cyanobacterial EPS due to these properties [18][19][20]. For example Xu et al [21] have been investigated in uence of molecular weigth on adsorption behavior of cyanobacterial EPS on colloidal particle.…”

Section: Introductionmentioning

confidence: 99%

Insights into the Viscoelastic Peculiarities of Cyanobacterial Extracellular Polymeric Substance (EPS)

et al. 2022

View full text Add to dashboard Cite

Extracellular polymeric substances (EPSs) can be de ned as renewable, high molecular weight polymeric materials produced by bacteria and microorganisms. EPSs are composed of primarily polysaccharides and proteins, with minor amounts of nucleic acids, lipids, and humic substances. Cyanobacterial extracellular polymeric subtances have a signi cant physiological effect on bloom formation and stress tolerance in adverse conditions. Therefore, cyanobacterial EPS has an important factor for aquatic life, environment and human life. For these reasons, determining the structure and structure-property relationships of cyanobacterial EPS is important for understanding its behavior and performance. In this study, the identi cation of the structure-property relationships, thermal and viscoelastic properties of cyanobacterial extracellular polymeric substance, X-ray diffraction (XRD) analysis, differential thermal analysis (DTA) and dynamic mechanical analysis (DMA) have been performed. Viscoelastic properties of the polymeric materias have been interpreted by certain DMA parameters at a xed frequency depending on the temperature to understand the performance of cyanobacterial EPS.

show abstract

Characteristics and bacterial community dynamics during extracellular polymeric substance (EPS) degradation of cyanobacterial blooms

Cited by 30 publications

References 61 publications

Insights into the role of external layers in cyanobacteria at varying temperatures and their regulatory mechanism

Insights into the role of external layers in cyanobacteria at varying temperatures and their regulatory mechanism

Gross Negligence: Impacts of Microplastics and Plastic Leachates on Phytoplankton Community and Ecosystem Dynamics

Insights into the Viscoelastic Peculiarities of Cyanobacterial Extracellular Polymeric Substance (EPS)

Contact Info

Product

Resources

About