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A Possible Function of Entamoeba Histolytica in the Creation Model

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A Possible Function of Entamoeba Histolytica in the Creation Model Answers Research Journal 2 (2009):117–121. www.answersingenesis.org/arj/v2/function-entamoeba-histolytica.pdf A Possible Function of Entamoeba histolytica in the Creation Model Frank Sherwin, Institute for Creation Research, 1606 Royal Lane, Dallas, TX 75229 Abstract Parasitology is the study of the symbiotic interaction between two different species of organisms in which one (parasite) lives in or on the other (host) and is metabolically dependent upon it. This large field includes the study of community and microbial ecology. Man and animals provide the ecological niches parasites inhabit and other organisms (for example, symbionts) they encounter. There is a need for parasites such as Entamoeba histolytica to be addressed from a biblical perspective that may include their original symbiotic or mutualistic association in man. E. histolytica is a protozoan parasite of the family Entamoebae that is found throughout the world killing approximately 100,000 people per year. Eight amoebas (Endolimax nana, Entamoeba coli, E. histolytica, E. dispar, E. hartmanni, Iodamoeba bütschlii, E. moshkovskii and E. polecki) reside in the human intestinal lumen. In the pre-fallen world there was true ecological harmony with an intimate association of individuals of different species (symbiosis). Creation microbiologists are currently investigating the role of single-celled eukaryotic creatures in the organosubstrate model. While the controlling factors that direct invasiveness of E. histolytica are not well understood, the progression from originally free-living single-celled eukaryotes (neutral or beneficial) toward a pathogenic condition after the Fall could have occurred through a number of mechanisms leading to a parasitic condition. Keywords: microbial ecology, organosubstrate, parasitism, creation Introduction example, E. hartmanni) today may reflect the pre-Fall Allaby (1992) defined parasitology as condition. Such undisruptive association could have the study of small organisms (parasites) living on or been mutualistic, just as Escherichia coli is within in other organisms (hosts), regardless of whether the the human host today. After the Fall God cursed effect on the hosts is beneficial, neutral or harmful. all of creation, for example the ground was cursed The wide field of parasitology is a study of community with thorns and thistles (Genesis 3). In addition, ecology and association patterns as it applies to host, the removal of some of God’s sustaining power could parasite and their environment (Caron et al. 2009; have resulted in a conversion via displacement and Patterson and Banks 2001; Roberts and Janovy modification leading from neutral or beneficial 2009). Meerovitch (1982) stated, protozoa to pathogenic species (Francis 2009). A The host-parasite relationship in amoebiasis is synthesis of organosubstrate model (and possibly among the most complex ones in parasitic infections serial endosymbiosis) with single-celled ecology may in general. help in our understanding of free-living amoeba (or Amoebas are complex, single-celled eukaryotic protists originally mutualistic amoeba) and their transition that utilize pseudopodia for locomotion. Entamoeba to parasitism. Indeed, the hypothesis (Bergman histolytica is the causative agent of amoebiasis that 1999) of the creation model of microbiology includes occasionally results in death. Given the ubiquity of bacteria, fungi and protozoans that may have been amoebas, one might ask how they were related to man beneficial, commensal (symbiotic association between and animal in a pre-Fallen world. Such a hypothesis two species in which one benefits, the commensal, would aid in describing the origin of parasitism (that and the other is not affected) or mutualistic in their is, amoebiasis) after the Fall. interaction with people and animals. Scripture teaches that prior to the Fall, everything was very good (Genesis 1:31). There was true Classification of the Amoeba ecological harmony with an intimate and extended Roberts and Janovy (2009) stated scientists association of individuals of different species have been occupied for over two centuries regarding (symbiosis). In fact, amoebas seemed to be designed the “monumental” task of classifying eukaryotic to form symbiotic communities. Several species of microorganisms. Amoeba are defined as single-celled harmless amoebas living in the human intestine (for eukaryotic protists. In decades past amoebas were ISSN: 1937-9056 Copyright © 2009, 2017 Answers in Genesis, Inc. All content is owned by Answers in Genesis (“AiG”) unless otherwise indicated. AiG consents to unlimited copying and distribution of print copies of Answers Research Journal articles for non-commercial, non-sale purposes only, provided the following conditions are met: the author of the article is clearly identified; Answers in Genesis is acknowledged as the copyright owner; Answers Research Journal and its website, www.answersresearchjournal.org, are acknowledged as the publication source; and the integrity of the work is not compromised in any way. For website and other electronic distribution and publication, AiG consents to republication of article abstracts with direct links to the full papers on the ARJ website. All rights reserved. For more information write to: Answers in Genesis, PO Box 510, Hebron, KY 41048, Attn: Editor, Answers Research Journal. The views expressed are those of the writer(s) and not necessarily those of the Answers Research Journal Editor or of Answers in Genesis. 118 F. Sherwin classified within the Phylum Protozoa. However, the mechanical vectors such as cockroaches and flies term protozoa is colloquial and used today as a common are also a potential source of infection. A significant noun with no taxonomic significance. There is much portion of the homosexual population is infected uncertainty regarding utility, classification schemes, through fecal/oral contamination (Noble et al 1989) and the alleged common ancestry of the amoeba where it can reach epidemic levels. (Roberts and Janovy 2009). Currently the amoeboid After being eaten by a new host, cysts are protozoa belong to a major group called the Amoeboza. transported to the small and large intestine. The In 2006 Adl and 27 others attempted to classify this cysts pass through the stomach unscathed and large group of eukaryotes (Adl et al. 2006). Regardless, display no activity while exposed to the low pH. But the taxonomy of the amoebas remains “extremely upon reaching the higher pH of the small intestine, unsettled” (Roberts and Janovy 2009). Evolutionists metacysts start to move within the walls of the cyst do not know the origin of amoebas, parasitic or benign, which weaken and open. Excystation (emergence) and numerous amoebic genes lack homologs in other occurs and the quadrinucleate amoebas divide into systems (MacFarlane and Singh 2007). Evolutionists amoebulas (daughter cells of encysted amoeba) and do place E. histolytica on a branch of the eukaryotic move rapidly downstream. The amoebas reside in the diagram based on rRNA phylogenies (Clark and lower portion of the small intestine and the lumen of Roger 1995), but they can say only that all organisms the large intestine. The trophozoites reproduce via “probably” evolved from a common, single-celled binary fission within the crypts of the large intestine progenitor (Lodish et al. 2008, p. 4). Current molecular mucosa (where pH is more stable), apparently feeding data used, in the case to answer classification questions on mucous secretions, polysaccharides and undergoing of single-celled creatures, has been contrary to older metabolic interaction with proteobacteria. Although classification systems. The Archamoebae (ancient or intestinal bacteria evidently are important in function primitive amoeba) are a very diverse collection, and for and growth of amoebas, it is not well understood that reason some evolutionists “doubt the phylogenetic and biologists continue to investigate this complex unity of the group” (Keeling 1998, p. 89). Creationists relationship. In terms of the organosubstrate model, the maintain diverse groups of microorganisms were bacteria perhaps protected the host while the amoebas created after their kind to be ubiquitous, abundant provided an as-yet unidentified benefit. Indeed, and form symbiotic microbial communities (Francis evidence accumulates regarding immune system 2003). benefits of good bacteria (Mazmanian 2009). Under the “right” conditions (for example, pathogenesis of the Ecology of Entamoeba histolytica amoeba, immunity status and nutrition of the host and Amoebas may be parasitic (for example, E. the bacterial flora) the trophozoites may initiate tissue histolytica), commensal or free living. Eight amoebas invasion when they break down mucosal cells and (Endolimax nana, Entamoeba coli, E. histolytica, E. absorb the products. The amoebas at this point no longer dispar, E. hartmanni, E. moshkovskii, E. polecki, and need bacterial presence to satisfy their nutritional Iodamoeba bütschlii) reside in the human intestinal demands. This parasite has a number of mechanisms lumen (Diamond and Clark 1993; Tanyuksel and to invade host tissues that includes contact-dependent Petri 2003) as evident commensals, deriving a niche cytolytic mechanisms and biochemical mechanisms and sustenance. That these amoebas contribute to a such as secreted hydrolytic enzymes (proteinases, mutualistic relationship cannot be determined as no phosphatases and glycosidases). benefit can be seen in the host. There are two exceptions Those individuals
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