Microorganisms marine

Estimates indicate that 10 tons of carbon dioxide are fixed globally per year, of which one-third is fixed in the oceans, primarily by photosynthetic marine microorganisms. 

Saxitoxin (STX) is a toxin which is found in marine microorganisms. It is most likely synthesized by bacteria which live in symbiosis with dinoflagellates, a component of phytoplankton. Through the marine food chain, it can lead to poisoning of humans. The mechanism of toxicity of saxitoxin is vety similar to that of tetrodotoxin. Saxitoxin binds from the outside of the membrane to various forms of voltage-sensitive Na+channels and blocks the channel in an activation state-independent manner. 

Phenazines — This large class of compounds includes more than 6,000 natural and synthetic representatives. Natural phenazines are secondary metabolites of certain soil and marine microorganisms. The main phenazine producers are Pseudomonas and Streptomyces species. Pseudomonas strains produce the most simple phenazines tubermycin B (phenazine-1-carboxylic acid), chlororaphine, pyocyanin, and iodinine. Pyocyanin is a blue pigment while chlororaphine is green both are produced by Pseudomonas aeruginosa. They can be seen in infected wounds of animal and human skins. Iodinine is a purple phenazine produced by Pseudomonas aureofaciens. 

Various substituted 1,2,5-thiadiazoles have been patented as antimicrobial agents in particular for marine microorganisms C1997USP5703102, 1997USP5661165, 1997USP5633219, 1996USP5491155, 1996USP5488060>. 

Berdicevsky and coworkers125 reported the conversion of inorganic lead into organic derivatives by marine microorganisms. 

Hudson, R. J. M. and Morel, F. M. M. (1993). Trace-metal transport by marine microorganisms - implications of metal coordination kinetics, Deep-Sea Res. Part... 

Dobretsov S, Dahms HU, Qian PY (2006) Inhibition of biofouling by marine microorganisms and their metabolites. Biofouling 22 43-54... 

Jenkins KM, Jensen PR, Fenical W (1998) Bioassays with marine microorganisms. In Haynes KF, Millar JG (eds) Methods in chemical ecology bioassay methods. Kluwer Academic, pp 1-37 Jensen PR, Jenkins KM, Porter D, Fenical W (1998) Evidence that a new antibiotic flavone glycoside chemically defends the sea grass Thalassia testudinum against zoosporic fungi. Appl Environ Microb 64 1490-1496... 

Patil KC, Matsumura F, Boush GM. 1972. Metabolic transformation of DDT, dieldrin, aldrin, and endrin by marine microorganisms. Environ Sci Technol 6 629-632. 

Raiswell R, Fisher QJ (2000) Mudrock-hosted carbonate concretions a review of growth mechanisms and their influence on chemical and isotopic composition. J Geol Soc 157 239-251 Roden EE, Lovley DR (1993) Dissimilatory Fe (111) reduction by the marine microorganism Desulfuromonas acetoxidans. App Environ Microbio 59 734-742... 

Roden EE, Lovley DR. 1993. Dissimilatory Fe(III) reduction by the marine microorganism Desulfuromonas acetoxidans. Appl Environ Microbiol 59 734 2. 

Seafood may naturally contain small amounts of various PAHs, absorbed from the sea water. The aquatic environment is contaminated with PAHs due to oil spills, incomplete combustion of fossil fuels, industrial and urban effluents, extraction from creosoted wharfs and pilings, as well as from biosynthesis by plants and marine microorganisms. 

An interesting and important example of an animal poison is paralytic shellfish poison (PSP). This chemical, which is also known as saxitoxin and by several other names as well, is found in certain shellfish. But it is not produced by shellfish it is rather a metabolic product of certain marine microorganisms (Protista). These microorganisms are ingested by the shellfish as food, and their poison can remain behind in the shellfish s tissue. Paralytic shellfish poison is not a protein, but a highly complex organic chemical of most unusual molecular structure. 

A. B. Mindler and S. T. Bateman, Pilot Plant Study on Marine Microorganisms and Organic Matter, Permutit, May 1980,... 

Hopkinson BM, Morel EMM (2009) The Role of Siderophores in Iron Acquisition by Photosynthetic Marine Microorganisms. Biometals 22 659... 

Walker JD, Colwell RR. 1975. Some effects of petroleum on estuarine and marine microorganisms. Can J Microbiol 21(3) 305-313. 

Integrated Approach To Explore the Potential of Marine Microorganisms for the Production of Bioactive Metabolites... 

Diversity and First Results on an Indigenous Group of Marine Microorganisms. 212... 

Fig.1. Total number of metabolites from marine microorganisms (1966-1999)...

What are marine bacteria Defining them as bacteria with an absolute requirement for sodium chloride is not a practical solution, because many marine isolates may tolerate quite a wide range of salinities, prompting speculation that they are in fact terrestrial organisms that have been swamped into the oceans from rivers, estuaries and sewage outfalls. Pragmatically, marine microorganisms are therefore defined as bacteria that have been isolated from marine sources on marine media [16]. 

However, one has to bear in mind that the microbial ecology of marine habitats has been revolutionized by cultivation-independent analyses based on 16S rRNA. It is now well documented that only a fraction of the marine microbial diversity has been cultivated, presumably far less than 1% [17], no more than the tip of the iceberg [18]. Clone fibraries of marine bacterioplankton 16S rRNA genes are dominated by a few phylotypes that have not been cultivated to date, and which are distributed globally [19,20]. It can therefore be concluded that the true marine microorganisms are in most cases presently not known. 

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