Amoeba histolytica

Unmodified antisense PNA oligomers were also recently shown to downregu-late targeted genes in an amoeba (Entamoeba histolytica) [68]. These results suggest the potential development of PNA as a new class of antimicrobial drugs. 

Martin, J.-B., Laussmann, T., Bakker-Grunwald, T., Vogel, G., and Klein, G., 2000, neo-inositol polyphosphates in the amoeba Entamoeba histolytica. J. Biol. Chem. 275 10134-10410. 

Several enzymes using PPj as phosphoryl donor have been described in bacteria and parasitic amoebae [22-24]. In both Propionibacterium shermanii and the eukaryote Entamoeba histolytica, the enzyme PPi-phosphofructose dikinase has been found [39,40]. This enzyme uses PPj as the phosphoryl donor to fructose-6-phosphate instead of ATP ... 

The enzyme has been discovered in the leaves of topical grasses such as sugar cane [47], in the amoeba E. histolytica [48], in Bacteroides symbiosus [49], in P. shermanii [50], in Acetobacter xylinum [51] and in several photosynthetic bacteria including R. rubrum [52]. The dikinase appears to function in different directions in different organisms. For example in A. xylinum, P. shermanii, and in the C4 plants it functions in the direction of P-enolpyruvate formation. On the other hand, in E. histolytica and B. symbiosus, this enzyme provides a means of formation of pyruvate and ATP. 

One genus of amoebae responsible for a number of diseases are the Entamoeba, found particularly in the gastrointestinal tract of humans, E. histolytica invades and destroys the tissues of the gut wall causing amoebic dysentery and ulceration of the gut wall. Infection of the liver by this species causes amoebic hepatitis, E. gingivalis, found within the spaces between the teeth, is associated with periodontal disease and gingivitis. 

It is a common but nonpathogenic amoeba present in humans which is often confused with . histolytica. 

Biocidal compounds against Entamoeba histolytica, a parasite causing amoebiasis. The Schiff base-related complexes 26 and 27 are active in vitro, metronidazole, (28) is commonly used in the medication of amoebiasis. In the diagram on the left, the activities of metronidazole, the complexes 26, 27 and VO(acac)2 and the free ligands (L) of 26 and 27 are compared. The IC50 values indicate the concentrations at which growth of 50% of the amoebae is inhibited. 

In studying the nutritional requirements of the amoebas, Nakamura and Baker (Nl) found that bacteria-free Entamoeba histolytica could be... 

Figure 31 The Exemplary Amoeba (A. histolytica) Is Imitated by Canca- Cells. [2345] Refaence Appendix 2, Explanations to the Figures...

The nutritional requirements of the parasitic amoebae, most frequently Endamoeha histolytica have been of interest to a great many investigators ever since Boeck and Drbohlav first cultured the dysentery amoeba. Aside from E. invadens, a reptilian parasite, and in spite of enormous effort, no parasitic form has been successfully cultured in vitro in the absence of other living organisms. Even for E. invadens fresh snake tissue or minced chick embryo or fresh liver slices must be added. We know, however, that E. histolytica multiplies abundantly in sterile abcesses, so it seems... 

Infestation with harmful amoebas, particularly Entamoeba histolytica. Cysts of the amoeba may be ingested in contaminated food or water. Also, flies, and infested animals may carry the organisms to foods. 

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