Regulatory mechanisms, microbial

For a number of reasons, there are some important limitations to the extension of this principle. Biodegradation—as opposed to biotransformation—of complex molecules necessarily involves a number of sequential reactions each of whose rates may be determined by complex regulatory mechanisms. For novel compounds containing structural entities that have not been previously investigated, the level of prediction is necessarily limited by lack of the relevant data. Too Olympian a view of the problem of rates should not, however, be adopted. An overly critical attitude should not be allowed to pervade the discussions—provided that the limitations of the procedures that are used are clearly appreciated and set forth. In view of the great practical importance of quantitative estimates of persistence to microbial attack, any procedure—even if it provides merely orders of magnitude—should not be neglected. 

John Wiley and Sons, 1972. A collection of essays describing microbial processes used in Japanese industry for the production of amino acids. Includes examples in which the regulatory mechanisms functioning in most cells have been modified or bypassed. 

Metabolic production in plant cells is subject to more complex regulatory mechanisms than metabolic production in microbial cells. 

In the first part of this chapter, we deal with insecticides including miticides and nematocides, which include very useful compounds such as avermectins and milbemycins, produced by bacteria and fungi. We list out microbial insecticides of importance and review the works mainly on the mode of action and biosynthesis of each metabolite. In the next part, major mycotoxins are listed and recent topics on them, especially on their biosynthesis, are described. Since contamination of two major mycotoxin groups, aflatoxins (AFs) and trichothecenes, in food and feed is a worldwide problem, they are treated in detail in the last part of this chapter. Recent studies on their biosynthesis, regulatory mechanism for their production, and inhibitors of their production are described. 

Demain, A. L. 1968. Regulatory mechanisms and the industrial production of microbial metabolites. Lloydia 31,395-418. 

At the present time, we can cite more examples of enzyme modification occurring as regulatory mechanisms in animal metabolism than we can in microbial metabolism. In animal metabolism, phosphorylation by protein kinases affects many enzymes (13). 

In conclusion, both plant cell/tissue and microbial systems offer tremendous advantages as scalable alkaloid production platforms. Moreover, because the characteristics and metabolic capacities of plant cell/tissue and microbial systems are inherently different, they can serve as complementary unit operations in order to solve the long-standing problem of robust alkaloid production. However, better understanding of regulatory mechanisms and refinement for robust cellular and metabolic engineering of plant ceUs/tissues will further provide an impetus to popular use of plant cell technology in industry. 

The discovery of a global regulatory system for virulence in S. aureus, mediated by small auto-inducing peptides (AlPs) has opened a new avenue to the interruption of microbial defences, and consequently, to overcoming resistance to many antibiotics. Microbial defensive mechanisms, based on mutation, drug efflux pathways, biofilm formation and the secretion of virulence factors, have become the major threat to modem antibiotic therapy. 

The results are of comparative interest but may have little bearing on the present discussion because the regulatory mechanisms for microbial fatty acid synthesis and for fatty acid synthesis in animal tissues appear to operate at quite different sites of control. Apart from the obvious absence of primary hormonal signals in bacteria, the following differences stand out. Only animal tissue acetyl-CoA carboxylase is activated by citric acid bacterial, plant and yeast carboxylase do not respond to this type of allosteric modulation. Similarly, microbial acetyl-CoA carboxylases are much more resistant to inhibition by palmitoyl-CoA at least at the concentration which inhibit the hepatic enzyme. 

Inflammation is a defense reaction of an organism against harmful stimuli such as tissue injury or infectious agents. Upon microbial invasion, an effective immuno-regulatory cascade is activated to protect the body against the intruders. The defense mechanisms that protect an organism against infections can be divided into... 

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