Indirect defense

Viral infections continue to be significant causes of morbidity and mortality and at the same time continue to be resistant to treatment by small molecules. Avridine (6) is an antiviral compound which has shown some activity in a variety of animal tests apparently based upon its ability to stimulate a number of cells to produce the high molecular weight endogenous antiviral substance interferon. Thus, the compound is believed to operate indirectly by stimulating the body s own natural defenses against viral penetration into host cells. Avridine is synthesized by... 

In addition to protecting the pteropod, pteroenone 37 can also serve invertebrates as an indirect chemical defense (Fig. 2). The amphipod Hyperiella dilatata gains protection by carrying the pteropod Clione antarctica on its back. That this carrying behavior provides efficient protection is clear, since in all cases... 

A remarkable indirect strategy for chemical defense is found in embryos of the shrimp Palaemon macrodactylusy which are resistant to infection by the pathogenic fungus Lagenidium callinectesy a known pathogen of many crustaceans. This resistance is caused by bacteria on the surface of the embryos... 

Pohnert G (2005) Diatom/copepod interactions in plankton the indirect chemical defense of unicellular algae. ChemBioChem 6 946-959... 

Similar to the CNBM, the GDBM has been regarded as a supply-side model, as it emphasizes that the levels of defenses are indirectly determined by the supply of secondary metabolites, rather than actively regulated in order to fulfill defensive demands. The GDBM is based on the premise that there is a physiological trade-off... 

Pohnert G (2004) Chemical defense strategies of marine organisms. In Schulz S (ed) Chemistry of pheromones and other semiochemicals, vol 1. Springer, Berlin, pp 179-219 Pohnert G (2005) Diatom/copepod interactions in plankton the indirect chemical defense of unicellular algae. ChemBioChem 6 946-959... 

Finally, the antifungal properties of a-pinene and limonene, two monoter-penes frequently found in the defensive secretion of Nasutitermes termites, was studied. In vitro assays showed that these molecules reduce spore germination of the fungus Metarhizium anisopliae through direct and indirect (vapor) contact [225]. Moreover, some diterpenes isolated from these insects have also an antibiotic activity on Bacillus subtilis, Staphylococcus aureus, and Enterococcus faecalis [226]. 

Complement. Complement is an extensive series of glycoproteins and protein inhibitors whose function includes major cytolytic effects, mediation of opsonization, and modulation of inflammatory responses. Activation of this system plays an important role in host defense leading to destruction of microorganisms. It also results in generation of anaphylotoxins which induce mediator release and "split products" that mediate membrane damage, either directly through structural alteration or indirectly, via cell chemotaxis and regulation. 

Targeting Volatile Terpene Biosynthesis for Manipulating Indirect Plant Defenses... 

Other aspects of implementing indirect volatile defenses, as recently discussed in several excellent reviews [17, 94, 95], will include the assessment of timing and synergy of volatile emissions with direct defense responses of the herbivore-damaged plant, especially if indirect defense strategies will be integrated with toxin-based pest control strategies. 

Yuan JS, Kollner TG, Wiggins G, Grant J, Degenhardt J, Chen F (2008) Molecular and genomic basis of volatile-mediated indirect defense against insects in rice. Plant J 55 491-503... 

Kant MR, Ament K, Sabelis MW, Haring MA, Schuuiink RC (2004) Differential timing of spider mite-induced direct and indirect defenses in tomato plants. Plant Physiol 135 483 95... 

Kollner TG, Held M, Lenk C, HUtpold I, Turlings TCJ, Gershenzon J, Degenhardt J (2008) A maize ( )-beta-caryophyUene synthase implicated in indirect defense responses against herbivores is not expressed in most American maize varieties. Plant Cell 20 482-494... 

Degenhardt J (2009) Indirect defense responses to herbivory in grasses. Plant Physiol 149 96-102... 

Predatory fish may also be affected by alarm pheromones (Section 7.2) of the prey, both directly and indirectly. The alarm odor may act as defense compoimd that inhibits predator attack or reduces capture rate by inducing predator avoidance in school members of the prey species. 

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