Algicidal effects of Morganella morganii on different bloom-forming cyanobacteria in freshwater environments
Start Date
24-5-2022 5:45 PM
End Date
24-5-2022 7:00 PM
Abstract
Cyanobacterial harmful algal blooms (cHABs) are a serious problem at a global scale. Among the different mitigation strategies, biological control by algicidal bacteria is receiving increasing attention. In this study we isolated a bacterial strain with algicidal properties from a toxigenic Microcystis spp. bloom occurred in a lowland reservoir in Poland (Central Europe). Analysis of the 16S rRNA gene identified the strain as Morganella morganii (99.51% similarity). The ability of this bacterium to lyse different bloom-forming cyanobacterial strains including, among others, the genera Microcystis and Aphanizomenon, both axenic and environmental, as well as toxigenic and non-toxigenic, was characterized. Microscopic cell counting and qPCR results showed that M. morganii killed the tested cyanobacterial strains after three days of co-culture. Interestingly, the ultra-high-performance liquid chromatography-tandem mass spectrometer (UHPLC-MS/MS) analyses unravelled that this bacterium was capable of producing several compounds with algicidal potential. This is the first study that demonstrates the algicidal properties of M. morganii, providing new insights into how these ubiquitous bacteria interact with bloom-forming cyanobacteria in nature. Therefore, this knowledge is the basis for further development of nature-based solutions that include algicidal microorganisms to regulate the presence of cHABs in freshwater.
Research funded: National Science Centre 2019/33/B/NZ8/02093 “ALGICYDY”
Algicidal effects of Morganella morganii on different bloom-forming cyanobacteria in freshwater environments
Cyanobacterial harmful algal blooms (cHABs) are a serious problem at a global scale. Among the different mitigation strategies, biological control by algicidal bacteria is receiving increasing attention. In this study we isolated a bacterial strain with algicidal properties from a toxigenic Microcystis spp. bloom occurred in a lowland reservoir in Poland (Central Europe). Analysis of the 16S rRNA gene identified the strain as Morganella morganii (99.51% similarity). The ability of this bacterium to lyse different bloom-forming cyanobacterial strains including, among others, the genera Microcystis and Aphanizomenon, both axenic and environmental, as well as toxigenic and non-toxigenic, was characterized. Microscopic cell counting and qPCR results showed that M. morganii killed the tested cyanobacterial strains after three days of co-culture. Interestingly, the ultra-high-performance liquid chromatography-tandem mass spectrometer (UHPLC-MS/MS) analyses unravelled that this bacterium was capable of producing several compounds with algicidal potential. This is the first study that demonstrates the algicidal properties of M. morganii, providing new insights into how these ubiquitous bacteria interact with bloom-forming cyanobacteria in nature. Therefore, this knowledge is the basis for further development of nature-based solutions that include algicidal microorganisms to regulate the presence of cHABs in freshwater.
Research funded: National Science Centre 2019/33/B/NZ8/02093 “ALGICYDY”