Tag : Existing

Washington: Scientists have detailed a lifestyle switch that occurs in marine bacteria, where they change from coexisting with algae hosts in a mutually beneficial interaction to suddenly killing them. The results are published today in eLife. Details of this lifestyle switch could provide new insights into the regulation of algal bloom dynamics and its impact on large-scale biogeochemical processes in environments">marine environments. Single-celled algae, known as phytoplankton, form oceanic blooms which are responsible for around half of the photosynthesis that occurs on Earth, and form the basis of marine food webs. Therefore, understanding the factors controlling phytoplankton growth and death is crucial to maintaining a healthy marine ecosystem. Marine bacteria from the Roseobacter group are known to pair up and coexist with phytoplankton in a mutually beneficial interaction. The phytoplankton provide the Roseobacter with organic matter useful for bacterial growth, such as sugar and amino acids, and the Roseobacter in return provides B-vitamins and growth-promoting factors. However, recent studies have revealed that Roseobacters undergo a lifestyle switch from coexistence to pathogenicity, where they kill their phytoplankton hosts. A chemical compound called DMSP is produced by the algae and is hypothesised to play a role in this switch. "We have previously identified that the Roseobacter Sulfitobacter D7 displays a lifestyle switch when interacting with the phytoplankter Emiliania huxleyi," states first author Noa Barak-Gavish, a PhD graduate in the Department of Plant and Environmental Sciences, Weizmann Institute of Science, Israel. "However, our knowledge about the factors that determine this switch was still limited." T ...