Cyanobacterial mats

There are numerous reports on herbivorous waterfowl and mammals that have died following consumption of cyanobacterial mats (e.g., Krienitz et al. 2003 WHO 2003). Most deaths are probably due to incidental ingestion of contaminated water during drinking or while feeding on aquatic macrophytes. 

Stal LJ (2000) Cyanobacterial mats and stromatolites. In Whitton BA, Potts M (eds) The ecology of cyanobacteria their diversity in time and space. Kluwer Academic, Netherlands,... 

Johnson et al. (1999) measured 5 " Se in volatilized Se, presumably in the form of alkylselenides, that was generated by cyanobacterial mats and incubated soils. For the cyanobacteria, an early sample of a vigorously growing culture yielded no measurable difference between the volatilized Se and the growth medium, whereas a later sample was enriched in the hghter isotope by 1.1 %o. In the soil volatilization experiments, four samples from two different incubated soils were analyzed. All of the samples 8 Se values were within 0.6%o of the total Se in the soil. Both the cyanobacteria and soil experiments were not highly controlled, but they do suggest that isotopic fractionation related to volatilization is small. 

MacMillan, J. B., Emst-Russell, M. A., de Ropp, J. S., and Molinski, T. F. (2002). Lobocycla-mides A-C, lipopeptides from a cryptic cyanobacterial mat containing Lyngbya confervoides. J. Org. Chem. 67, 8210-8215. 

MacMillan JB, Molinski TF (2005) Majusculoic Acid, a Brominated Cyclopropyl Fatty Acid from a Marine Cyanobacterial Mat Assemblage. J Nat Prod 68 604... 

Jorgensen, B.B., Revsbech, N.P., Blackburn, T.H. and Cohen, Y., 1979. Diurnal cycle of oxygen and sulfide-microgradients and microbial photosynthesis in a cyanobacterial mat sediment. Appl. Environ. Microbiol., 38 46-58. 

Fig. 12. Total ion current trace of the Curie-point pyrolysis gaschromatography mass spectrometry run of fossil sheath tubes isolated from the Solar Lake cyanobacterial mat sediments (Boon, 1984) 521...

Boon, J. J. Tracing the origin of chemical fossils in microbial mats Biogeochemical investigations of Solar Lake cyanobacterial mats using analytical pyrolysis methods, in Microbial mats Stromatolites (eds. Cohen, Y., et al.) p. 318, New York, Alan R. Liss Inc. 

It is believed that the presence of secondary metabolites impacts on the survivorship of a cyanobacterial strain in reef habitats that are subject to intense herbivory. Under suitable environmental conditions, cyanobacteria undergo rapid increases in population size, generating large cyanobacterial mats which are not calcified or of tough texture and which therefore present a potential source of food for herbivorous fish and other generalist predators. By restricting predation, potent cyanobacterial toxins facilitate the formation of cyanobacterial blooms.48... 

Field and laboratory studies have not yet resolved the question of environmental regulation of scytonemin content. Either UV or high visible light exposure can affect scytonemin concentrations with both positive and negative correlations. Scytonemin concentrations monitored for a 20-month period in an intertidal cyanobacterial mat community have ten-fold temporal fluctuations that... 

Karsten, U., Maier, J., and Garcia-Pichel, F., Seasonality in UV-absorbing compounds of cyanobacterial mat communities from an intertidal mangrove flat, Aquat. Microb. Ecol., 16, 37, 1998. 

Jprgensen, B.B., and Des Marais, D.J. (1986) Competition for sulfide among colorless and purple sulfur bacteria in cyanobacterial mats. FEMS Microbiol. Ecol. 38, 179-186. 

Monomethyl and dimethylalkanes in the range C16-C20 are prominent in many cultured cyanobacteria as well as most cyanobacterial mat communities that have been studied (Section 8.03.5.3). No specific physiological role has been assigned to these hydrocarbons. Because they have probably multiple origins in ancient sediments and petroleum, these monomethyl and dimethylalkanes alone probably have limited chemotaxonomic specificity. However, they may be very useful in multivariate approaches for linking isotopic and molecular-structure data for a less ambiguous identification of sedimentary cyanobacterial lipids. 

Kenig F., Sinninghe Damste J. S., Kock-van Dalen A. C., Rijpstra W. I. C., Hue A. Y., and de Leeuw J. W. (1995b) Occurrence and origin of mono-, di-, and trimethylalkanes in modem and Holocene cyanobacterial mats from Abu Dhabi, United Arab Emirates. Geochim. Cosmochim. Acta 59, 2999-3015. 

Shiea J., Brassell S. C., and Ward D. M. (1990) Mid-chain branched mono- and dimethyl alkanes in hot spring cyanobacterial mats a direct biogenic source for branched alkanes in ancient sediments Org. Geochem. 15, 223-231. 

The nucleation of a calcitic or aragonitic form is species specific, and they grow where conditions are also favorable for abiotic carbonate deposition. The filamentous cyanobacterial mats may passively accumulate and bind local sedimentary particles that become entombed through cementation with additional calcium carbonate. 

Frund C. and Cohen Y. (1992) Diurnal cycles of sulfate reduction under oxic conditions in cyanobacterial mats. Appl. Environ. Microbiol. 58, 70—77. 

Teske A., Kuver J., Jorgensen B. B., Cohen Y., Ramsing N. B., Habicht K., and Fukui M. (1998) Sulfate-reducing bacteria and their activities in cyanobacterial mats of Solar Lake (Sinai, Egypt). Appl. Environ. Microbiol. 64, 2943—2951. 

Krumbein, W.E., Cohen, Y. and Shilo, M., 1977. Solar Lake, (Sinai) 4. Stromatolitic cyanobacterial mats. Limnol. Oceanogr., 22 635—656. 

Four new cytotoxic disulfides, rostratins A-D 57-60, were isolated from the broth of the marine-derived fungus Exserohilum rostratum (Drechsler), a fungal strain found associated with a marine cyanobacterial mat. These compounds showed in vitro cytotoxicity against human colon carcinoma (HCT-116) with IC50 values of 8.5, 1.9, 0.76, and 16.5 pg mL, respectively. 

The bathtub analogy can be used to consider many aspects of sequestration on the Earth. The most obvious problem, the storage of water in the oceans rather than the mantle, has already been discussed above. A similar problem is the sequestration of oxygen in the air. In the late Archaean Earth, the photosynthetic cause of the flow of oxygen production through the tap was presumably in cyanobacterial mats and global cyanobacterial plankton. This view is based on the evidence for the presence of cyanobacteria (Buick 1992). Bacteria spread very rapidly and once cyanobacteria had evolved they would have occupied every available niche very quickly. Just as rabbits filled Australia within a few decades, so cyanobacteria would spread globally within a very few years of their first evolution. If they are present in one place, they will be present planet-wide. 

Cyanobacterial mats in modem hypersaline environments also release significant quantities... 

The major processes of cyanobacterial mats are shown in Figures 2 and 3. 

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