Growth, death, and photobiology of dinoflagellates (Dinophyceae) under bacterial-algicide control
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Naturally occurring allelopathic compounds, specific to some phytoplankton, may be a good source of bio-control agents against microalgae responsible for harmful algal blooms (HABs). Global expansion of HABs has invigorated research into different approaches to control these algae, including the search for naturally derived algicidal compounds. Here, we investigated the effects of a filtrate from the algicidal marine bacterium Shewanella sp. IRI-160 on photochemical function of four cultured dinoflagellates, Karlodinium veneficum, Gyrodinium instriatum, Prorocentrum minimum, and Alexandrium tamarense. The filtrate (designated IRI-160AA) contains bioactive compound(s), which were recently shown to inhibit growth of several dinoflagellate species. Results of this study show that all dinoflagellates but P. minimum exhibited photosystem II (PSII) inhibition, loss of photosynthetic electron transport, and varying degrees of cellular mortality. Exposure assays over 24 h showed that PSII inhibition and loss of cell membrane integrity occurred simultaneously in G. instriatum, but not in K. veneficum, where PSII activity declined prior to losing outer-membrane integrity. In addition, PSII inhibition and population growth inhibition were dose-dependent in K. veneficum, with an average EC-50 of 7.9 % (v/v) IRI-160AA. Application of IRI-160AA induced significantly higher PSII inhibition and cell mortality in K. veneficum subjected to continuous darkness as compared to cells maintained with 12:12 h light/dark cycles, while no such dark effect was noted for G. instriatum. The marked differences in the rate and impact of this algicide suggest that multiple cellular targets and different cascades of cellular dysfunction occur across these dinoflagellates.
KeywordsBacterial algicide Dinoflagellates Photobiology PSII HAB Membrane permeability
This work was supported by the National Oceanic and Atmospheric Association (NOAA) Prevention, Control and Mitigation of HABs (PCM HAB) program (Grant #NA10NOS4780136 to KJC and MEW).
- Anderson DM, Burkholder JM, Cochlan W, Glibert PM, Gobler CJ, Heil CA, Kudela RM, Parsons ML, Rensel JEJ, Townsend DW, Trainer VL, Vargo GA (2008) Harmful algal blooms and eutrophication: examining linkages from selected coastal regions of the United States. Harmful Algae 8:39–53PubMedCrossRefPubMedCentralGoogle Scholar
- Einhellig FA (1999) An integrated view of allelochemcials amid multiple stresses. In: Inderjit, Dakshini KMM, Foy CL (eds) Principles and practices in plant ecology: allelochemical interactions. CRC, Boca Raton, pp 479–494Google Scholar
- Faust MA, Larsen J, Moestrup Ø (1999) Potentially toxic phytoplankton. 3. Genus Prorocentrum (Dinophyceae). In: Lindley JA (ed) ICES identification leaflets for plankton. Leaflet no. 184. Copenhagen, pp 1–24Google Scholar
- Fukuyo Y (1985) Morphology of Protogonyaulax tamarensis (Lebour) Taylor and Protogonyaulax catenella (Whedon and Kofoid) Taylor from Japanese coastal waters. Bull Mar Sci 37:529–537Google Scholar
- HAB RDDTT (2008) In: Dortch Q, Anderson DM, Ayres DL, Glibert PM (eds) Harmful algal bloom research, development, demonstration, and technology transfer national workshop report. Woods Hole, Massachusetts, USAGoogle Scholar
- Heisler J, Glibert P, Burkholder J, Anderson D, Cochlan W, Dennison W, Dortch Q, Gobler C, Heil C, Humphries E, Lewitus A, Magnien R, Marshall HG, Sellner K, Stockwell D, Stoecker DK, Suddleson M (2008) Eutrophication and harmful algal blooms: a scientific consensus. Harmful Algae 8:3–13CrossRefGoogle Scholar
- Jungo E, Visser PM, Stroom J, Mur LR (2001) Artificial mixing to reduce growth of the blue-green alga Microcystis in Lake Nieuwe Meer, Amsterdam: an evaluation of 7 years of experience. Water Sci Technol Water Supply 1:17–23Google Scholar
- Rensel JE, Whyte JNC (2003) Finfish mariculture and harmful algal blooms. In: Hallegraeff, GM, Anderson DM, Cembella AD (eds) Manual on harmful marine algae, revised edn. IOC UNESCO, pp 693–722Google Scholar
- Rounsefell GA, Evans JE (1958) Large-scale experimental test of copper sulfate as a control for the Florida red tide. US Fish Wld S Spec Sci Rep 270Google Scholar