According to the research there have been several attempts by biologists to induce higher organisms. This is believed to be achieved through the use of chemicals and make them transmissible in series as hereditary characters. It provides an example of such changes to include the specific alterations of the cell structure to enable them to reproduce under defined conditions for a specific type of pneumococcus. This is attributed to the success of Griffith who transformed an attenuated and non-encapsulated variant into a fully encapsulated and virulent cell of a specific type.
Another example presented included the interconvertibility of pneumococcal types in the field of viruses. Berry and Dedrick were successful in changing the rabbit fibroma making it an infectious myxoma. Their research was done by inoculating rabbits with a mixture of active fibroma virus in combination with heat-activated myxoma virus and produced in animal symptoms. Upon the passage of the transformed virus, it became transmissible and induced myxomatous infection which is similar to the lesion characteristics of naturally occurring disease. The paper provided a more detailed analysis of the transformation of specific types of pneumococcus. The area of focus was to isolate active principle from crude bacterial extracts and determine possible chemical nature or sufficiently characterize in the group of chemical substances. The working model that was adopted for this model was familiar to most people making it appropriate for conducting the analysis. This research provided the transformation of non-encapsulated R variant of pneumococcus Type II to Pneumococcus Type III.
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According to the research, the Type III pneumococci which were biologically active faction had been isolated in its purified form which according to researchers in minutes was able to transform encapsulated R variants of type II pneumococcus into a fully encapsulated cells of as that of heat-killed microorganism like that from which an inducing material was recovered.
Avery’s study presents some weaknesses. It is not possible for transforming principle was made of DNA. It is important to point out the fact Avery was aware of the fact that DNA that was being used contained small quantities of protein that could produce a transforming effect. According to an article by Mirsky and Arthur 1946, traces of protein are always present in even the best prepared nucleic acid preparations, and thus 1 or 2 percent could be present in “pure” or protein free” nucleic acid. This goes against the fact that Avery experimental data which stated that they used DNA as the only sole active component.
The data presented in the articles stated that the chemical, enzymatic and serological analysis, ultraviolet spectroscopy, unbound lipid, and the electrophoresis showed that the active factions contained no demonstrable protein and consisted of a principally polymerized form of deoxyribonucleic acid. It is important to point out the fact that there is a high probability for traces of proteins to exist in “pure” DNA extracts. The protein could be bound to DNA while two substances were being isolated. Given the fact that DNA is made of four bases, it is not clear how it would be possible for it differently affects genes genes. It for certain that four bases were constantly repeated. It was based on the stated items in the article that they concluded something that is not agreed upon by other scholars.
