Microbiology metabolic products

Bacterial corrosion is often referred to as microbiologically influenced corrosion. MIC involves the initiation or acceleration of corrosion by microorganisms. The metabolic products of microorganisms appear to affect most engineering materials, but the more commonly used corrosion-resistant alloys, such as stainless steels, seem to be particularly susceptible. 

Scheme of microbiological metabolic pathways for biogas production... 

Within the network Marine Biotechnology in Lower Saxony [29] an integrated approach between research groups in microbiology, natural product chemistry, biotechnology, and medicine is underway to systematically explore the metabolic capabihties of North Sea bacteria for the production of bioactive compounds with respect to their phylogenetic position. 

The inhibited polymer films may simultaneously present a barrier for electrochemical and microbiological corrosion. Table 2.11 and Fig. 2.43 illustrate data from [5, 6, 54] characterizing the capability of PE films containing Cl of the PHC series to inhibit vitality of microscopic fungi and bacteria whose metabolic products evoke corrosion damage of metals. 

Water used in extmsion starch does not only transfer the system into the thermoplastic condition, but also partially protects the polymer from destmction. Addition of water and others hydroxide-containing substances are used for disposable or not long-term application. In this connection mixes of starch with synthetic polymers get the increasing value. These materials combine properties of the synthetic component present in them and have the ability of biodegradation due to the presence of a natural biodecomposed component - starch in the system [6-9]. It is necessary to note, that biodecomposition of films with similar structures (on method astm-d-5209-92) occurs actively with allocation of co2, microbiological weights and the metabolic products useful to plants [7]. 

Microbiologically influenced corrosion inhibition (MICI) represents the counterpart to microbiologically influenced corrosion or biocorrosion (MIC). Whereas in the latter case materials are damaged due to detrimental effects exerted by microorganisms or their metabolic products, the former describes the phenomenon of... 

Haskins, R.H., Thorn, J.A., Boothroyd, B., 1955. Biochemistry of the Ustilaginales. XI. Metabolic products of Ustilago zeaein submerged culture. Canadian Journal of Microbiology 1, 749-756. 

Poor correlation of microbiological plate counts to shelf life is likely due to two factors. First, spoilage is not always related to the number of organisms present. The type of bacteria present rather than the actual numba s determines the types and the extent of off-flavor development and consequently the end of shelf life. Second, poor flavor and shelf life can also be attributed to the presence of microbial enzymes and metabolic products from organisms present before pasteurization. In some cases, pasteurization can kill microorganisms but not inactivate microbial enzymes. 

Nitrite (or compounds at the same or lower oxidation level) is produced microbiologically from nitrate, and may then react with the substrate to produce stable end products. The production of nitrite is the sole metabolic function of the bacteria and, in view of concern over the presence of nitrate in groundwater, the following possible environmental significance of these or analogous reactions should not be overlooked ... 

Microbiologically influenced souring (MIS) is the production of H2S through the metabolic activities of microorganisms. A better chance for mitigating MIS in some down-hole environments using biocides may be possible if the problem is detected early in the souring process [1259]. However, if the... 

Berry, A., Dodge, T.C., Pepsin, M. and Weyler, W. (2002) Application of metabolic engineering to improve both the production and use of biotech indigo. Journal of Industrial Microbiology Biotechnology, 28, 127—133. 

Nielsen, J. (1998) The role of metabolic engineering in the production of secondary metabolites. Current Opinion in Microbiology, 1, 330—336. 

Pfeifer, B., Hu, Z., Licari, P. and Khosla, C. (2002) Process and metabolic strategies for improved production of Escherichia coli-derived 6-deoxyerythronolide B. Applied and Environmental Microbiology, 68, 3287-3292. 

Murli, S., Kennedy, J., Dayem, L.C. et al. (2003) Metabolic engineering of Escherichia coli for improved 6-deoxyerythronolide B production. Journal of Industrial Microbiology and Biotechnology, 30 500—509. 

Butler, M.J., Bruheim, P, Jovetic, S. et al. (2002) Engineering of primary carbon metabolism for improved antibiotic production in Streptomyces lividans. Applied and Environmental Microbiology, 68, 4731 4739. 

The establishment of quantitative methods for the determination of vitamins in body fluids and tissues by microbiological assay techniques should stimulate the search for the significance of vitamins in disease, not only in nutritional deficiency, but in the much wider field of all metabolic disturbances. Functional vitamin deficiencies are produced by malabsorption, by inhibitors of the vitamin function through products of the body, and particularly through drugs and other toxic substances. Vitamin deficiencies may be relative deficiencies whenever an individual s metabolism is deranged so as to require enhanced quantities of a given vitamin to cure or to counteract certain symptoms as, e.g., in Darier s disease (keratosis follicularis) (P2a). 

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