Plant microorganisms involved

Nitrification is a vital step in the process of biological elimination of nitrogen in sewage plants. The consortium of microorganisms involved in this process is usually very sensitive to many pollutants from different industrial and agricultural sources. The rapid detection of such pollutants is essential for processing of sewage. 

Borneman, J., Olatinwo, R., Yin, B., Becker J.O. An experimental approach for identifying microorganisms involved in specified functions utilisation for understanding a nematode suppressive soil. Australasian Plant Pathol 2004 33 151-155. 

Nothing is known about the biosynthesis of the maytansine group, the only ansamycins so far identified as being of plant origin. Their similarity to the bacterial metabolite geldanamycin has led to the hypothesis that despite their occurrence in plants, microorganisms might be involved in their production. 

Although terpenoid biosynthesis in plants, animals and microorganisms involves similar classes of enzymes, important differences exist among these processes. Plants produce a much wider variety of terpenoids than do either animals or microbes. 

To sort out the relative importance of these, or additional hypotheses for explanation of enhanced EPTC degradation in soil, it is important that the microorganisms involved be identified and that the biochemical pathway(s) by which they degrade EPTC be determined. Although several different pathways have been proposed for carbamothioate degradation in soil, current information is based on studies conducted in animal and plant systems (10-12). 

The main steps involved in the decomposition of organic substances, and in the synthesis and decomposition of humus in soils, are shown in Fig. 6.1, drawn by Nikiforoff (1938). The rate and extent of transformation of the various animal and plant substances into gaseous products and residual substances, including humus, minerals, water and synthesized materials, are dependent primarily on the conditions under which decay takes place, and on the microorganisms involved. These factors are discussed in the following pages. 

Bioprocess plants which use microorganisms and/or enzymes, such as fermentation plants, have many characteristics similar to those of chemical plants. Therefore, an engineering approach to the design and operation of various plants which involve biological systems would be valuable, provided the differences in the physical properties of some materials are taken into account. 

There are large numbers of reported case histories of MIC on stainless steel in water and aqueous waste systems. They are related to different industrial applications such as freshwater storage and circulation systems in nuclear power plants [103, 113,116,142] and cooling water systems in chemical process industries [117,118]. There are basically three cases (a) crevice corrosion under unexpected deposits, (b) sensitivity of pitting and crevice corrosion to trace of H2S, and (c) crevice corrosion in natural seawater. Most of these reports are not well documented concerning the microorganisms involved in the process. However, some general features are... 

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