Prokaryotic diversity

Modern approaches based on the use of molecular techniques presumed to circumvent the need for culturing prokaryotes, fail to provide sufficient and reliable information for estimation of prokaryote diversity. Many properties that make these organisms important members of the living world are amenable to observation only through the study of living cultures. Since current culture techniques do not always satisfy the need of providing a balanced picture of the microflora composition, future developments in the study of bacterial diversity should include improvements in the culture methods to approach as closely as possible the conditions of natural habitats. Molecular methods of microflora analysis have an important role as guides for the isolation of new prokaryotic taxa. 

Palleroni NJ. 1997. Prokaryotic diversity and the importance of culturing. Ant V Leeuwenhoek 72 3-19. 

Cifuentes, A., Anton, J., Bendoch, S., Donnelly, A., Herbert, R. A., and Rodriguez-Valera, F. (2000). Prokaryotic diversity in Zostera noltii—Colonized marine sediments. Appl. Environ. Microbiol. 66,... 

Garcia-Martinez,., Acinas, S. G., Anton, A. I., and Rodriguez-Valera, F. (1999). Use of the 16S-23S ribosomal genes spacer region in studies of prokaryotic diversity.J. Microbiol. Methods 36, 55-64. 

Madrid, V. M., AUer, J. Y., AUer, R. C., and Christoserdov, A. Y. (2001). High prokaryote diversity and analysis of community structure in mobile mud deposits off French Guiana Identification of two new bacterial candidate divisions. FEMS Microbiol. Ecol. 37, 197—209. 

These examples demonstrate a general problem in marine microbiology, namely that the large prokaryotic diversity comprises adaptations to very diverse environments and that only a very small fraction, maybe less than one percent, of the bacterial species in the ocean is known to science today. Many of the unknown microorganisms may... 

Hugenholtz P. (2002). Exploring prokaryotic diversity in the genomic era. Genome Biol., 3 REV1EWS0003. 

Kemp, P.F., Aller, J.Y. (2004). Estimating prokaryotic diversity when are 16S rDNA libraries large enough Limnology and Oceanography Methods 2, 114-125. 

Biogeography an emerging cornerstone for understanding prokaryotic diversity, ecology, and evolution. Microbial Ecology S3,197-207. 

Curtis, T., Sloan, W., Scannell, J. (2002). Estimating prokaryotic diversity and its limits. Proceedings of National Academy of Science United States of America, 99, 10494—10499. 

Mohapatra BR, Gould WD, Dinardo O, Koren DW (2011) Trackiug the prokaryotic diversity in add mine drainage-contaminated environments a review of molecular methods. Miner Eng 24 709-718... 

Oren, A. 2004. Prokaryote diversity and taxonomy current status and future challenges. 

In comparison to prokaryotic cells, eukaryotic cells are much greater in size, typically having cell volumes 10 to 10 times larger. Also, they are much more complex. These two features require that eukaryotic cells partition their diverse... 

Microtubules are universally present in eukaryotes from protozoa to the cells of higher animals and plants (Porter, 1966 Hardham and Gunning, 1978 Lloyd, 1987), but they are absent in mammalian erythrocytes and in prokaryotes. Microtubules participate in a number of cellular functions including the maintenance of cell shape and polarity, mitosis, cytokinesis, the positioning of organelles, intracellular transport to specific domains, axoplasmic transport, and cell locomotion. The diversity of microtubule fimctions suggests that not all microtubules are identical and that different classes of microtubules are present in different cell types or are localized in distinct domains in the same cell type (Ginzburg et al., 1989). 

Formate dehydrogenases are a diverse group of enzymes found in both prokaryotes and eukaryotes, capable of converting formate to CO2. Formate dehydrogenases from anaerobic microorganisms are, in most cases, Mo- or W- containing iron-sulfur proteins and additionally flavin or hemes. Selenium cysteine is a Mo- ligand. 

The oxidation of carotenes results in the formation of a diverse array of xanthophylls (Fig. 13.7). Zeaxanthin is synthesised from P-carotene by the hydroxylation of C-3 and C-3 of the P-rings via the mono-hydroxylated intermediate P-cryptoxanthin, a process requiring molecular oxygen in a mixed-function oxidase reaction. The gene encoding P-carotene hydroxylase (crtZ) has been cloned from a number of non-photosynthetic prokaryotes (reviewed by Armstrong, 1994) and from Arabidopsis (Sun et al, 1996). Zeaxanthin is converted to violaxanthin by zeaxanthin epoxidase which epoxidises both P-rings of zeaxanthin at the 5,6 positions (Fig. 13.7). The... 

Detmers J, V Briichert, KS Habicht, J Knever (2001) Diversity of snlfnr isotope fractionation by snlfate-redncing prokaryotes. Appl Environ Microbiol 67 888-894. 

Due to the usual diversity of components in the medium, there will be a need to consider that the species taken up interacts with other species while diffusing towards the organism surface (see Figure 19). In some cases (as in the aquatic prokaryotes that exudate Fe chelators called siderophores to improve the availability of Fe see Chapter 9 in this volume), the medium is modified on purpose by the organisms [11,47-49], A simple model for this interaction assumes the complexation of M with a ligand, with elementary interconversion kinetics between the free and complexed forms ... 

RP-HPLC has also been applied for the study of the effect of salinity on the diversity of prokaryotic and eukariotic phytoplankton. Seawater samples were fdtered and the filters were sonificated with acetone and left for 24 h at 4°C. Separation was performed in an ODS column (250 X 4.6 mm i.d. particle size 5 pm). The concentrations of pigments are compiled in Table 2.100. 

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