Diversity of microorganisms

A large diversity of microorganisms has been shown to degrade pyridine. Numerous studies have been performed and a large number of metabolites have been detected. The proposed hypothetical pathway was constructed to fit all the results. Certain set of intermediates were identified for specific microorganisms and some enzymes were also identified or detected (e.g., aliphatic intermediates). However, the mechanism(s) of cleavage of the pyridine ring remain(s) unknown. 

Bioavailability is also influenced by certain, albeit poorly understood, characteristics of bacteria. To degrade soil-sorbed molecules, bacteria must either use sorbed molecule directly or facilitate desorption in some manner. Mechanisms underlying the apparent availability of sorbed chemicals are complex due to the divergent properties of chemicals considered, the resultant sorption/desorption mechanisms, the metabolic diversity of microorganisms, and the heterogeneity of soils. Several microbial-based mechanisms have been proposed for the access of soil-sorbed organic chemicals (i) production of bio surfactants (Desai and Banat 1997 Alexander 1999) ... 

Schrenk, M. O., D. S. Kelley, J. R. Delaney and J. A. Baross, 2003, Incidence and diversity of microorganisms within the walls of an active deep-sea sulfide chimney. Applied and Environmental Microbiology 69, 3580-3592. 

As one may expect from the diversity of microorganisms that can reduce iron, the spectrum ranges from bacteria that can use only amorphous Fe(III) hydroxide/oxide (e.g., T. ferrireducens) and apparently require direct contact with the Fe(III) precipitate, as shown by electron micrographs (Slobodkin et al. 1997b), to bacteria that can utilize various forms of Fe(III) ion as precipitated hydroxide or as complexed soluble ions, such as Fe(III) citrate, to bacteria such as T. saccharolyticum that can use only soluble Fe(III) citrate but are stimulated by the addition of increased Fe(III) ions. Further studies must to be done to elucidate the nature and which of the bacteria excrete electron mediators (so no direct contact would be required) and which contain cell-wall-bound reductases (which require a direct contact with the Fe(III) precipitate). 

Table 5.8 Biological diversity of microorganisms, estimated from the rate of discovery of new species ...

Our planet is home to an extraordinarily rich diversity of microorganisms with a vast range of metabolic pathways. Even in a single soil sample there can be thousands of different microbial species, yet only a tiny fraction of this microbial diversity can be cultured under standard laboratory... 

Edwards, K.J., Bach, W., and McCollom, T.M., 2005, Geomicrobiology in oceanorgraphy Microbe-mineral interactions at and below the seafloor, Trends in Microbiol. 13 449-456 Schrenk, M.O., Kelley, D.S., Delaney, J.R., and Baross, J.A., 2003, Incidence and diversity of microorganisms within the walls of an active deep-sea sulfide chimney, Appl. Environ. Microbiol. 69 3580-3592 Schrenk, M.O., Kelley, D.S., Bolton, S., and Baross, J.A., 2004, Low archaeal diversity linked to sub-seafloor geochemical processes at the Lost City Hydro-thermal Field, Mid-Atlantic Ridge, Environ. Microbiol. 6 1086-1095. 

Due to the diversity of microorganisms or cells it may be impossible for a person skilled in the art to repeat the invented solution without undue experimentation (a certain degree of experimentation to gain experience is acceptable) or without some inventiveness of his own. Therefore, it is mandatory in such cases to deposit a sample of the microorganisms or cells at an approved depository institution in order to provide the necessary enabling disclosure and to meet the requirements of a patent application (see below Deposition of Microorganisms). 

The enormous diversity of microorganisms is a factor that must be kept in mind for future drug development. Only a minor proportion of bacteria and fungi have been cultured or examined for secondary metabolite production. For example, only 5% of the total number of fungal species have been described. Of those described (69,000), only 16% (11,500) have been cultured. It has been estimated that 1 gram of soil contains 1000 to 10,000 species of undiscovered prokaryotes The extensively used concept of isolation of microbial strains fixim different geographical and climatic locations around the world still gathers support. ... 

Further studies have also demonstrated that thermophilic degradation of PAHs and nonvolatile hydrocarbons increased at temperatures likely to occur adjacent to the active treatment zone of an in situ thermal remediation site (Huesemann et aL, 2002). This observation is likely the result of shifts in the population of microorganisms from predominantly mesophUic to predominantly thermophilic. This type of community shift is usually associated with a reduction in the diversity of microorganisms. As subsurface temperatures cool after active thermal treatment, the consortia within the heated zone will again shift as conditions become less favorable for thermophUes and return to the optimum temperatures for mesophiles. The EPA Technology Innovation Office has pubhshed a more detailed review of this topic, available at the website www.clu-in.org. 

Local versus global diversity of microorganisms cryptic diversity of ciliated protozoa. Oikos SO, 220-225. 

Considering the diversity of microorganisms that may be found in other environments, the cast of characters that emerge during winemaking is limited. The explanation generally offered for this centers on the interactive and cumulative effects of ethanol and pH combined with nutrient depletion and the use of preservatives in processing. 

Fertilizer use in general increases soil fertility, enriches their with soil microflora. Unilateral fertilizer application decreases diversity of microorganisms, while use of combined organic-mineral fertilizer contributes to its conservation. For all that many species of protolithic bacteria influence on processes of phosphorus transformation in conditions of aftereffect fertilizer in agroecosystems. 

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