Electronic Resource
Investigating the Mechanism Behind the Release of Microcystins in Freshwater Cyanobacteria
| العنوان: | Investigating the Mechanism Behind the Release of Microcystins in Freshwater Cyanobacteria |
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| المؤلفون: | Ryan, Ken, Puddick, Jonathan, Nicolai, Rossella |
| بيانات النشر: | Victoria University of Wellington 2020 |
| نوع الوثيقة: | Electronic Resource |
| مستخلص: | The frequency and distribution of toxic cyanobacterial blooms are increasing globally, creating the need for a better understanding of the processes involved in toxic secondary metabolite production. Microcystins (MCs) are potent hepatotoxins produced by a wide range of bloom-forming cyanobacteria genera such as Microcystis and Planktothrix. Although the release of MCs to the extracellular environment has long been considered a by-product of cell lysis and death, several studies suggest the presence of a mechanism that actively transports these toxins outside the cell membrane. The aim of the present study was to find evidence for a link between cell lysis and concentrations of extracellular MCs. A dual-fluorescence cell viability assay using the nucleic acid stain SYTOX Green was optimised for use on Microcystis and Planktothrix. A SYTOX Green concentration of 1 µM, and an incubation time of 30 minutes, yielded a bright and even fluorescent signal that readily identified lysed cells. The improved staining technique, in conjunction with liquid chromatography-mass spectrometry analyses, was employed in a culturing experiment to track the transfer of MCs to the extracellular environment in relation to the amount of cell lysis. For Microcystis, there was a strong and significant positive relationship between cell lysis and the concentration of extracellular MC. When the extracellular MC was predicted according to cell lysis levels and the MC content per cell, lysed cells were a major contributor of MCs to the extracellular environment, although the model overestimated the concentrations. Relationships for Planktothrix were significant but weaker, possibly due to reduced accuracy in the cell enumeration step, which would have altered the calculated MC content per cell. Whilst these findings support the hypothesis that cell lysis is the main contributor of extracellular MCs, the results do not exclude a role of MCs as signalling molecules. The recent finding that program |
| مصطلحات الفهرس: | Microcystis, Planktothrix, harmful algae, toxin export, cyanotoxin, SYTOX Green, microcystin, text, Masters |
| URL: | |
| الاتاحة: | Open access content. Open access content http://creativecommons.org/licenses/by-nd/3.0/nz Creative Commons GNU GPL Allow commercial use |
| ملاحظة: | en_NZ |
| Other Numbers: | UX0 oai:researcharchive.vuw.ac.nz:10063/9397 1231735759 |
| المصدر المساهم: | VICTORIA UNIV OF WELLINGTON LIBR From OAIster®, provided by the OCLC Cooperative. |
| رقم الانضمام: | edsoai.on1231735759 |
| قاعدة البيانات: | OAIster |
| الوصف غير متاح. |