Cyanobacteria morphology

Physical controls are generally only applicable in lakes. The infinence of river morphology on eutrophication is not sufficiently well understood to be used effectively. The exception to this would be the short-term use of high flow to reduce the retention time to levels which limit growth rates of nuisance species such as cyanobacteria. 

Camacho FA, Thacker RW (2006) Aniphipod herbivory on the freshwater cyanobacterium Lyngbya wollei. chemical stimulants and morphological defenses. Limnol Oceanogr 51 1870-1875 Carmichael WW (1994) The toxins of cyanobacteria. Sci Am 2780 78-86 Carmichael WW (2001) Health effects of toxin-producing cyanobacteria the cyanoHABs . Hum Ecol Risk Assess 7 1393-1407... 

Lengke, M.F., Fleet, M.E., Southam, G. 2006. Morphology of gold nanoparticles synthesised by filamentous cyanobacteria for gold(1)-thiosulfate and gold(lll)-chloride complexes. Langmuir, 22, 2780-2787. 

The observations have shown that consideration must be given to several different processes of carbonate deposition and/or silica or iron oxide deposition in contact which such bacterial mats. Obviously some important lithification processes take place within the decay zone below the active photosynthetic zone. In most of the cases where lithification was observed there, it was carbonate lithification of a type not related to the photosynthetic depletion of C02. Different filamentous and coccoid cyanobacteria can become more or less lithified depending on slime production, mobilization, outer morphology and microenvironments. 

The morphology of cyanobacteria varies widely, and they include spherical, ovoid, and cylindrical unicellular species, as well as multicellular colonial and filamentous forms (e.g. Coute and Bernard, 2001). Some species differentiate to form various specialized cells, such as heterocysts, which are able to fix nitrogen in water under N-limited eonditions, and akinetes, which allow them to survive when environmental conditions are not favorable for growth. This high phenotypic plasticity makes it rather difficult to identify cyanobacteria to the species level. 

Pescheck, G.A. and Sleytr, U.B. (1983) Thylakoid morphology of the cyanobacteria Anabaena variabilis and Nostoc MAC grown under light and dark conditions. J. Ultrastruct. Res., 82, 233-239. 

Photosynthetic prokaryotes such as cyanobacteria and photosynthetic bacteria lack chloroplasts and in these organisms the light reactions that drive photosynthesis take place in the cell s inner plasma membrane. The photosynthetic apparatus of purple bacteria, for example, is contained in a system of rntra-cytoplasmic membranes. Fig. 1 depicts the morphologies of two such purple bacteria - Rhodobacter (Rb.) sphaeroides [Fig. 1 (A)], formerly called Rhodopseudomonas sphaeroides, and Rhodopseudomonas (Rp.) viridis [Fig. 1 (B)] - species that are commonly used for photosynthesis studies. The former contains bacteriochlorophyll a (BChl a), which absorbs in the 800-880 run region in vivo, while the latter contains BChl b, which absorbs in the 960-1020 run region. 

Bolch, C.J.S. et al.. Genetic, morphological, and toxicological variation among globahy distributed strains of Nodularia (Cyanobacteria), J. Phycol, 35, 339, 1999. 

After cell lysis, the hepatotoxins can be extracted using several different solvent combinations. The differences in extraction efficiency are not solely dependent on the solvent used but also on the morphological differences of cyanobacteria and on the microcyst variants present in the cells [129]. However, many studies have investigated the most efficient extraction solvents for hepatotoxins [124,129-131], these indicate that the selection of solvents will vary depending on the sample type and its microcystin content. More recently, Barco et al. evaluated a wide range of extraction volumes... 

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