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Thursday, April 28

  1. page Brazil Nut Tree - Animal Symbiosis edited Brazil-Nut Tree Symbiosis's By Gregory Cello {Brazil-nut-fruit-hanging-from-branch.jpg} {Brazi…
    Brazil-Nut Tree Symbiosis's
    By Gregory Cello
    {Brazil-nut-fruit-hanging-from-branch.jpg} {Brazil-nut-tree.jpg} {agouti.jpg}
    Introduction
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  2. page Symbiotic Relationship between E. scolopes and V. fischeri edited ... They also studied whether or not the bacteria produced flagella. The V. fischeri strain is usu…
    ...
    They also studied whether or not the bacteria produced flagella. The V. fischeri strain is usually flagellated and motile, however once the symbiosis was established, these bacteria did not develop these characteristics. Once they were removed from the light organ however, they quickly were able to develop these appendages. “Thus, two important biological characteristics, growth rate and flagellation were modulated during establishment of the association, perhaps as part of a coordinated series of symbiotic responses.” This proves that this relationship not only needs specific environmental conditions, but also needs the bacteria to have certain morphological characteristics as well.
    Source: http://www.medmicro.wisc.edu/labs/mcfall_ruby_papers/pdf/1993/Ruby_Asato_1993_ArchMicrobiol.pdf
    ...
    Organ Development
    The toxin, cytotoxin is known to cause serious infections and health problems in humans and other animals. In the symbiotic relationship with squids however, it promotes the development of the light organ. This is important because it may cause all scientists to rethink the role of bacteria in the world. One of them states: “it is all context dependent. It has to be that we have mechanisms to use these molecules in different ways. Until now, molecules of a virulent nature have not been recognized as having essential roles in their development” says McFall-Ngai.
    In the Hawaiian bobtail squid, the toxin was found to promote development of the light organ, which is responsible for bioluminescence. When the squid are born, they are about the size of a grain of rice and they must acquire toxin-producing bacteria from their ocean environments. “Specialized features on the surface of the squid’s nascent light organ facilitate colonization by the bacteria, which in turn, promote the development of the functioning light organ. If you deprive the animal of those microbes, the system simply doesn’t develop.” This is further evidence of the specificity of the light organ in this interesting symbiotic relationship.
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  3. page Symbiotic Relationship between E. scolopes and V. fischeri edited ... This proves the specificity of the light organ in the E. scolopes, which include physiological…
    ...
    This proves the specificity of the light organ in the E. scolopes, which include physiological and biochemical controls of expression of luminescence. This study removed the bacterial from the light organ environment and observed the results. Immediately after the removal from the light organ, the symbionts visibly which were visibly luminous, decreased their bioluminescence substantially. This process was not reversed by culturing the bacteria on any of a variety of laboratory media. The variation in luminescence of different strains of the symbionts appeared to also be due to the different rates of autoinducer synthesis. The conclusion from this experiment proved that the bacteria and the squid both need extremely specific conditions in order to produce bioluminescence.
    Source: Depressed Light Emission by Symbiotic Vibrio fischeri of the Squid Euprymna scolopes
    ...
    Light Organ
    When the juvenile squids emerge from its egg, it is symbionts-free and it must obtain a bacterial infection from the surrounding environment, in order to survive. This study documented the process of the squid acquiring its symbionts. When placed in seawater containing only few colony-forming-units, the juvenile squid became quickly infected. “Colonization of the nascent light organ was initiated with as few as 1 to 10 bacteria, which rapidly began to grow at an exponential rate until they reached a population size of approximately 105 cells by 12h after the initial infection.” The number of bacteria was maintained.
    They also studied whether or not the bacteria produced flagella. The V. fischeri strain is usually flagellated and motile, however once the symbiosis was established, these bacteria did not develop these characteristics. Once they were removed from the light organ however, they quickly were able to develop these appendages. “Thus, two important biological characteristics, growth rate and flagellation were modulated during establishment of the association, perhaps as part of a coordinated series of symbiotic responses.” This proves that this relationship not only needs specific environmental conditions, but also needs the bacteria to have certain morphological characteristics as well.
    ...
    Bacterial Toxins Govern Organ Development
    The toxin, cytotoxin is known to cause serious infections and health problems in humans and other animals. In the symbiotic relationship with squids however, it promotes the development of the light organ. This is important because it may cause all scientists to rethink the role of bacteria in the world. One of them states: “it is all context dependent. It has to be that we have mechanisms to use these molecules in different ways. Until now, molecules of a virulent nature have not been recognized as having essential roles in their development” says McFall-Ngai.
    ...
    symbiotic relationship.
    Source:
    http://www.eurekalert.org/pub_releases/2004-11/uow-iat110904.php
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    7:04 am
  4. page Symbiotic Relationship between E. scolopes and V. fischeri edited ... Bioluminescent marine bacteria Vibrio fischeri, when cultured away from the light organ associ…
    ...
    Bioluminescent marine bacteria Vibrio fischeri, when cultured away from the light organ association with the squids depress their emission of light by over 1,000 fold. This is because of the underproduction of the autoinducer luciferase, which positively regulates this reaction. The autoinducer acts as a sensor that regulates the induction process, and eventually results in bioluminescence. If there are not enough bacteria, then this process obviously does not occur. This suggests that some conditions specific to the internal environment of the light organ are necessary for maximal autoinduction of luminescence in the symbionts of this squid-bacterial association.
    This proves the specificity of the light organ in the E. scolopes, which include physiological and biochemical controls of expression of luminescence. This study removed the bacterial from the light organ environment and observed the results. Immediately after the removal from the light organ, the symbionts visibly which were visibly luminous, decreased their bioluminescence substantially. This process was not reversed by culturing the bacteria on any of a variety of laboratory media. The variation in luminescence of different strains of the symbionts appeared to also be due to the different rates of autoinducer synthesis. The conclusion from this experiment proved that the bacteria and the squid both need extremely specific conditions in order to produce bioluminescence.
    GrowthSource: Depressed Light Emission by Symbiotic Vibrio fischeri of the Squid Euprymna scolopes
    Growth
    Rate and
    ...
    Light Organ
    When the juvenile squids emerge from its egg, it is symbionts-free and it must obtain a bacterial infection from the surrounding environment, in order to survive. This study documented the process of the squid acquiring its symbionts. When placed in seawater containing only few colony-forming-units, the juvenile squid became quickly infected. “Colonization of the nascent light organ was initiated with as few as 1 to 10 bacteria, which rapidly began to grow at an exponential rate until they reached a population size of approximately 105 cells by 12h after the initial infection.” The number of bacteria was maintained.
    They also studied whether or not the bacteria produced flagella. The V. fischeri strain is usually flagellated and motile, however once the symbiosis was established, these bacteria did not develop these characteristics. Once they were removed from the light organ however, they quickly were able to develop these appendages. “Thus, two important biological characteristics, growth rate and flagellation were modulated during establishment of the association, perhaps as part of a coordinated series of symbiotic responses.” This proves that this relationship not only needs specific environmental conditions, but also needs the bacteria to have certain morphological characteristics as well.
    Source: http://www.medmicro.wisc.edu/labs/mcfall_ruby_papers/pdf/1993/Ruby_Asato_1993_ArchMicrobiol.pdf

    Bacterial Toxins
    ...
    Organ Development
    Scientific research on

    The toxin, cytotoxin is known to cause serious infections and health problems in humans and other animals. In
    the light-organ
    Squids
    symbiotic relationship with squids however, it promotes the development of the light organ. This is important because it may cause all scientists to rethink the role of bacteria in the world. One of them states: “it is all context dependent. It has to be that we have mechanisms to use these molecules in different ways. Until now, molecules of a virulent nature have not been recognized as having essential roles in their development” says McFall-Ngai.
    In the Hawaiian bobtail squid, the toxin was found to promote development of the light organ, which is responsible for bioluminescence. When the squid are born, they are about the size of a grain of rice
    and Bioluminescencethey must acquire toxin-producing bacteria from their ocean environments. “Specialized features on the surface of the squid’s nascent light organ facilitate colonization by the bacteria, which in turn, promote the development of the functioning light organ. If you deprive the animal of those microbes, the system simply doesn’t develop.” This is further evidence of the specificity of the light organ in this interesting symbiotic relationship.
    Source:
    http://www.eurekalert.org/pub_releases/2004-11/uow-iat110904.php
    OTHER INTERESTING SOURCES:

    http://web.uconn.edu/mcbstaff/graf/VfEs/VfEssym.htm
    - Overview paper of what the symbiotic relationship between the squid/bacteria is
    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC213346/pdf/jbacter00121-0177.pdf

    - Paper talking about the specific conditions in the light organ necessary for the genes to be transcribed and translated
    http://www.medmicro.wisc.edu/labs/mcfall_ruby_papers/pdf/1996/Ruby_1996_AnnuRevMicrobiol.pdf
    - Paper describing the specific steps of initiation, establishment and persistence in the colonization of the light organ or the squids
    http://www.medmicro.wisc.edu/labs/mcfall_ruby_papers/pdf/1993/Ruby_Asato_1993_ArchMicrobiol.pdf

    -Paper arguing that growth rate and flagenation were modulated during the establishment of the symbiotic relationship. Suggests regulations of both physiological and morphological structures
    http://www.eurekalert.org/pub_releases/2004-11/uow-iat110904.php
    -Toxin regulates the development of the light organ

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  5. page The Human Microbiome and Individualized Response to Pharmaceuticals edited The The Human Microbiome ... Human Microbiome Projec Project {http://www.nature.com/nature…
    TheThe Human Microbiome
    ...
    Human Microbiome ProjecProject
    {http://www.nature.com/nature/journal/v449/n7164/images/nature06244-f1.2.jpg} Human Microbiome Project
    Introduction
    The human microbiome is a vast array of microbial members and the interactions they have with surrounding environments throughout the body. The challenge of fully comprehending the human microbiome and the intricacies of co-metabolic activity occurring amongst individual bacteria, pharmacologically derived byproducts, and the responding human gut can seem truly overwhelming . Introducing synthetic products into the equation only complicates the system more. Despite the advance of modern medicine, pharmaceuticals continue to be produced in a "one size fits most" manner. The microbiome regulates metabolic balance and homeostatic activity within the body and as a result, becomes unique to each individual and the particular environmental conditions that surround. As each microbiome becomes individualized, the possibility of side effects and unwanted results from specific pharmaceutical drugs becomes more and more likely. Despite the fact that pathologists and the healthcare industry have not reached a viable for of perso nalized medicine for the masses, newly produced drugs are subject to vigorous standards by the FDA. To grasp the consistent growth and diversity within the microbiome, the human intestines hold more than 10 times the amount of microbes than there are cells in the body (1).
    ...
    of Crohn's Disease
    Probiotics
    UCSF
    Disease. UCSF School of Pharmacy
    Björkstén

    Mechanics of the Microbiome
    In the past decade, the gut has been the focus of studies conducted regarding personalized pharmaceutical treatment. Although the microbiome technically includes nasal, oral, skin, and urogenital components, the gastrointestinal realm and the diverse mix of millions of microbe interactions have created new windows of opportunity. Several papers have gone so far as to suggest the microflora of the gut to be a “microbial organ” which resides in a surrounding host organ (2). Additionally researchers have also started to discover that each individual’s generalized mix of bacteria can also be responsible for individualized treatments to sickness. Michael Fischback of UCSF was quick to point out that many treatments to specific gut diseases have been derived from the co-metabolic by products that have been discovered in the past decade. This same finding does go in the opposite direction however, as bacteria can become pathogenically harmful and result in toxin production, intestinal putrefaction, and even carcinogenic production (3). Disease’s including Crohn’s disease stem from the problem that researchers have had shortcomings identifying how to identify these same toxins that prevent reoccurring bouts of sickness in patients. In recent studies, the use of prebiotics and probiotics has allowed researchers to manipulate the composition of the mammalian gut and thus control the direct interactions of certain microbes (4). In the past, most research of the mammalian gut and microbial communities have been limited by the internal nature of the symbiotic relationship. At present, in vivo analysis of the gut are allowing more and more surgical applications and metagenomic samples which allow for even more evaluation of the complex microbial interaction occurring (5). Ultimately, the fundamental mechanisms that create reactions between specific bacteria will have to be understood in a manner that will provide unexpected consequences with some baseline knowledge
    Probiotics – Induced Symbiosis
    The research and development of probiotic treatments has increased dramatically in the past 10 years. By introducing live microorganism to an existing problem, researchers have identified consistent relationships which have alleviated problems such as obesity, blood pressure, colon cancer, and general immune functioning (6). The implantation of these microorganisms will provide long-term benefits as scientist monitor the efficiency of the drugs they are inducing interaction with. P.D. Cani has recently discovered that probiotic treatment in early adult life can isolate the metabolic functions that lead to eventual obesity. Probiotics and prebiotics are historically an extremely new concept and from a business perspective are still very experimental. In comparison to pharmaceutical drugs however, the concept of introducing live microorganisms over synthetically derived chemicals does seem more appealing to certain shares of the current population. Probiotic supplementation has also proved to be significantly less harmful to developing children (7). Early supplementation of microorganisms to children has proven to boost immune response and even to alleviate the proliferation of allergic disease.
    {microbiome.jpg} Graphical analysis of organisms sequenced during the Human Microbiome Project
    Links to Human Microbiome Studies
    The Human Microbiome Project
    The CIHR Canadian Microbiome Initiative
    The International Human Microbiome Consortium
    Data Analysis and Coordination Center
    References
    1) Björkstén
    B, Sepp
    ...
    PMID 11590374.
    2) Nicholson JK, Holmes E, Wilson ID. Gut microorganisms, mammalian metabolism and personalized healthcare. Nat Rev Microbiol 2005; 3:431–438
    3) Microbiology of the Human Intestinal Tract and Approaches for Its Dietary Modulation
    D.M. Saulnier, S. Kolida and G.R. Gibson
    4) The Gut Microbiota in Inflammatory Bowel Disease
    G.T. Macfarlane, K.L. Blackett, T. Nakayama, H. Steed and S. Macfarlane
    5) The Gut Microbiota as a Target for Improved Surgical Outcome and Improved Patient Care
    J. Kinross, A.C. von Roon, N. Penney, E. Holmes, D. Silk, J.K. Nicholson and A. Darzi
    6) The Role of the Gut Microbiota in Energy Metabolism and Metabolic Disease
    P.D. Cani and N.M. Delzenne
    7) Probiotics, Immune Function, Infection and Inflammation: A Review of the Evidence from Studies Conducted in Humans
    A.R. Lomax and P.C. Calder

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  6. page Sponges and Cyanobacteria edited ... As mention earlier, sponges are excellent filter feeders as water is constantly circulating wi…
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    As mention earlier, sponges are excellent filter feeders as water is constantly circulating within and without the sponges’ canals. Filter feeding can provide method to transfer microorganisms and organic particles in and out of the sponge. Filter feeding contributes to the amount of microbes living within the sponges and enhances the sponge/microbe symbiotic relationship. In particular, the symbiotic relationship between the two benefits the marine environment greatly. Sponges are important members of the shallow and deep salt-water communities. Two examples, which easily illustrated this symbiotic relationship, are both nutrients supply by the photosynthetic symbionts and active microbes are derived from the microbes. Therefore, sponges and their microorganism associations provide assistance against their competitors - marine corals.
    What do we really know about sponge-microbe symbiotic associations?
    ...
    corals, the spongesponges symbiotic relationshiprelationships has currently
    {09185011245328444.png} Fig 2. The basic structure of a signal microorganism found in a marine sponge. Various microorganisms have been found in sponges. Microbes includes Proteobacteria, Actinobacteria, Nitrospira, Chloroflexi, Planctomycets, Cyanobacteria, and Acidobacteria.
    The questions raised and answered in both publications:
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  7. page Plant Animal Associations edited ... Additional Information on Solar Powered Sea Slugs {Photosynthetic Sea Slugs & Gene Transf…
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    Additional Information on Solar Powered Sea Slugs
    {Photosynthetic Sea Slugs & Gene Transfer.ppt}
    {Critical Review of Wagele.docx}
    {Rumpho 2008.pdf}
    {Wägele 2010.pdf}
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  8. page Plant Animal Associations edited ... Sea Slug--Algal Symbiosis {m9642c.jpg} ... for personal advantage. advantage to keep th…
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    Sea Slug--Algal Symbiosis
    {m9642c.jpg}
    ...
    for personal advantage.advantage to keep the plastids. The used
    1) acquired algal photosynthesis genes, germ line or otherwise
    2) sequestered algal photosynthesis genes
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