Host resistance and immunity

Topic:  Host resistance and Immunity Discuss the differences and similarities in the role thateach microorganism fulfills in their ecological niche.
Introduction
Ecological niche
Definition: An ecological niche refers to how a population or an organism reacts to the allocation of resources. This also includes those competing for resources, for instance, by growing when resources are plentiful, and when predators, parasites and pathogens are inadequate. Additionally, it comprises how it in turn changes those factors like restraining access to resources by other organisms, act as a source of food for predators and a consumer of prey (Berg, 2008).
Comparison and contrast of the roles of E-coli and Mycobacterium Tuberculosis in their ecological niche
Both Escherichia- coli and Mycobacterium tuberculosis can survive in hostile environments due to their adaptations to their environment. In case of any change in their genotypes, both bacteria are able seek food from other sources they have not been able to get their food. This allows these bacteria to keep away from the action of destructive chemicals for instance antibiotics. This can also allow them produce chemicals that shield them from attack by organisms that have the ability of destroying them (Schindler, 2006).
Both M. tuberculosis and Escherichia -coli have the small second-messenger molecule called cAMP in them as well as in the macrophage. When cAMP levels are high, it interferes with host indication pathways. However, cAMP levels within Mycobacterium Tuberculosis are many at times higher as compared to Escherichia coli. The high levels of cAMP generate it’s own series of troubles, for instance, with the purpose of the key bacterial cAMP-responsive protein, the cAMP receptor protein (CRP). These proteins manage the expression of a big number of bacterial genes by attaching to cAMP. This, in so doing undergoes allosteric alterations that enable it to attach to a definite DNA motif and as a result, interact with and engage the RNA polymerase-sigma factor complex, hence activate transcription initiation. In Mycobacterium tuberculosis, this has to happen against the conditions of extremely high cAMP levels (Qureshi, et. al, 1999).
Escherichia coli play a handy role in suppressing the growth of destructive bacteria species by combining appreciable amounts of vitamins. On the other hand, Mycobacterium tuberculosis evades the human immune response by attacking host cells (New York Times, 2012). Mycobacterium tuberculosis does this by creating an intracellular environment when macrophage overwhelms a M. tuberculosis cell. It then prevents the macrophage from combining with a lysosome which contains enzymes, which then crashes foreign bodies and pathogens that attack. It does this by generating some protein which the macrophage produces and changes the lysosome membrane. This prevents attachment, thus preventing the lysolytic enzymes from reaching their target. This interferes so much with the pathways of the immune system, therefore, avoiding its destruction (Schindler, 2006).
Conclusion
In a nutshell, Escherichia coli play a useful role by curbing the growth of harmful bacteria species which it does by synthesizing a considerable amount of vitamins thus preventing the bacteria establishment in the body. On the other hand, Mycobacterium tuberculosis causes serious infections in people with a normal immunity. This is because it is capable of attacking the host cells. It does this by creating an intracellular environment which obstructs the pathways of the immune system so much, therefore, avoiding its destruction (Schindler, 2006).
References
Berg, L. R. (2008). Introductory botany: Plants, people, and the environment. Belmont, CA: Thomson Brooks/Cole.
New York Times (2012) Health Guide. Immune response (n. d.) Retrieved 12th February, 2012 from http://health. nytimes. com/health/guides/specialtopic/immune-response/overview. html? inline= nyt-classifier
Qureshi, S. T., Skamene, E., & Malo, D. (1999). Comparative genomics and host resistance against infectious diseases. Emerging Infectious Disease, 5(1) Retrieved 12th February, 2013 fromhttp://www. cdc. gov/ncidod/eid/vol5no1/qureshi. html
Schindler, Lydia W. (2006). Understanding the Immune System. The National Cancer Institute. September 2003. Retrieved 12th February, 2013 from http://www. thebody. com/content/art6319. html#system