Work Of Bacillus Thuringiensis Biology Essay

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Have you eaten a fruit such as corn with worms. Do you even like sharing your own fruit with these pests. Is it the most appalling thing ever. I grew up in a tropical country, Philippines, and I am really fond eating fruits and vegetables. However, when I was young I started to have phobia with worms because these pests all came out on my favorite fruit, guava. I do not want any worms eating on my fruit and Biotechnology is the solution for these kinds of problems in agricultural crops, medicines and genetics. Biotechnology is the way of using other living things to improve human health. Besides that, our agriculture had been important after many decades and it has been the part of higher uprising around the world. Pest resistance have two definitions, it is either conducted by laboratory or the natural conditions. The laboratory scientists define pests' resistance as being qualified susceptible of strains to the controlling agent which is genetically mediated decrease of the target organism. It is based on statistics of the graph bacteria strains. Meanwhile the natural condition's definition is by nature. The experiment is conducted by nature's result. However, agricultures are controversial and impacted the scientific repercussion in biotechnology.

There have been paces in the development of tools that is practiced in cultivation; it is presently accessible to the biotechnology crops. Isolated by a Japanese person named Ishiwata, he gave it to a German scientist named Berliner who introduced Bt as a sporulation form and vegetative insecticidal proteins. He found thousands of strains and produces its own insecticidal crystal protein (delta-endotoxin) which encoded by single gene on a plasmid in the bacteria. The number of countries growing transgenic crops commercially has increased over time because it was demonstrated and design as synthetic genes as a result with the plant expression. It started at France when plants have been engineered to fight attack from insects and diseases. Now, it is the major technique for agriculture because it is more traditional ways to kill pests.

Over millions of hectares areas not only in United States have been genetically engineered with transgenic crops and GM crops. Some GM crops such as injecting Bt toxins a type of bacterium called Bacillus thuringiensis have been profoundly helped farmers and humans because the safety it brings and the effective killings of the pests inside a fruit. Without using chemical insecticides and pesticides in plantations, Bacillus thuringiensis is a microscopic insecticide that can be found everywhere especially near lakes and ponds. Using these bacteria, it is technique to get rid of some pests because it acts as protein called delta-endotoxin. These toxins produce crystal structures that are very poisonous to the specific species of an insect because the Bt gene has certain types that can affect the plants and our environment from the toxin. Bt toxin also helped to kill some pests because some insects could control the crops. When scientists conduct experiment, it was from the larvae that is bind in the gut of the pests. First we splice the Bt genes to make the toxin for specific pest target. Most of the Bt strains are close to each other excluding that each strains have been encoded. After splicing genes with specific encoded gene, the Bt gene will injected to the crops. As the plants naturally growing on the soil, the pests will eventually eat these crops and Bt crops will be eaten by pests. The toxin will be activated inside the gut cell of the insect because it will bind the Bt into the pest's receptors and the insects will suffer to hunger and die. Plants are being engineered because transgenic crops to have pest resistance and other tolerance to other living or non-living organisms. The good thing is all Bt strains are related to each toxins, but each strains are encoded with the specific target insect.

Food may be genetically changed because we sought to improve their lifespan. Also, we wanted to make the food to become nutritionally crop harvest and produce it to develop resistant to pesticides and chemical insecticides. As the DNA is the genetic material that controls expression each organisms, Bacillus thuringiensis crops DNA where been selected to insert the into the plant's own DNA created by the plant geneticist. In order to keep the essential agriculture, some countries choose hybrids for the Bt transformations for crop stability, disease resistance and crop's abilities. If the genes of these crops are injected into alternative kind of species, hence the organism is stated as transgenic because we use biotechnology to modify their genetic material. The cell completes new tasks when scientists or plant's geneticist quickly transformed cell to create new proteins by introducing a foreign gene. The Bacillus thuringiensis DNA is inserted into crop's DNA and through the variety of plant transformation techniques, the insertion site affect the Bt protein production because the components of the genetic protein vary. Therefore, companies cautiously examine the transformation for acceptable production of Bt protein to have no negative effect on the agriculture traits.

In addition, the cell of the plants will perform its functions when the delta-endotoxin genes use chemical messages to initiate the cell by making the proteins specific. Bacillus thuringiensis are produced numerous toxins because it is extensively used genetic changes. The chemical pesticides have definite specify for insects in several orders. There's a lot of transformation technique to transform the crops. Most widely used transformation technique is the lipofection and agrobacterium. In lipofection, the liposomes of the target genes in plants will be placed into a solution. The proteins will be the carriers of the selected plant's DNA. In the cell membrane of the crops, the DNA will let them access into the cell and will combine these liposomes with phospholipids. With successful transformation of an organism by insertion of exotic genetic material, measures vary in the genetic package injected into the organism and the precise place where this genetic protein is inserted into the host DNA. The genetic marker permit companies to recognize effective transformations such as B. thuringiensis toxins consumed by larvae as a protoxin and activated by proteases in the midgut of the larvae. The stimulated toxin is supposed to then bind variably to different forms of gut epithelial surface proteins. Next, it will introduce in the membrane, where it refolds to form pores in control for cell damage.

However, every crystal protein has been categorized in a vastly precise and limited insect host spectrum due to the established toxicity studies of single purified protein. The Bacillus thuringensis encodes a gene (Cry1) that produces the Cry-protein.  The Cry protein forms a crystal that pierces the gut of insects when they eat it.  Bt crops have this same gene inserted into their own genome.  So the entire DNA sequence of the gene that makes the Cry protein (the Bt-toxin) is removed from the Bacillus thuringensis bacterium, and placed inside the crop plant, so that it can produce the same toxin (the Cry protein).  This way, when bugs eat the plant, they are exposed to the same toxin, and are killed. The reason for narrow host spectrum is that the protein is not lethal to all bugs, because many insect species contain enzymes which allow for the protein to be degraded and destroyed once ingested.  Other insect species simply allow the protein to pass through their system entirely without lethality or even damage.   PCR is used in many steps along the process.  PCR would first be used to sequence the gene inside the bacterium.  Then again in various gene cloning steps before placement inside crop plant. Then finally to confirm gene insertion into host crop plant.  

Bt impacted our plantations through beneficial to our farmers and society. It greatly helped our plantations killing the pests to have healthy growing crops without even destructing our wildlife However, Bt resistant had been widely used and that Bt resistant has many problems developing to our surroundings. The researchers found out that the pests are becoming a resistant to the material and putting the foods and production at risks. The scientist found out that the strain of Bt resistant is now emerging to the root worms, beetles and other pests. As the insects or pests progress to the Bt resistance, it hovers the achievement of GMO and Transgenic crops with the Bt resistance technique. One major country who used Bt is China. China used Bt Cotton as a major agriculture though bollworms resistant to Bt cotton. Thus it affects their agricultural economy.

There are many controversies about the resistant management of Bt pesticides and resistance management for Bt plants is a crucial alarm. So far, researchers currently have available the refuge management. This management must be under maintenance to make certain of the insect population as liable alleles adequate and will occur. In each crop, the most significant is considering the variation and understanding the extensive time efficiency of the precise protein crop. The Bt plants only depends on the genetic basis of these resistance and as these strategies, the resistance of the toxins that is formed are evolving. Furthermore, another conflict is there is only one current available monitored management called high dose and refuge management. The frequency of these alleles must be able to survive by having low key heterozygous of the resistant alleles. Bt plants use the refuge to isolate the susceptible alleles within the population of the crop. However, it is expensive because the government needed a vast area of land to regulate the refuge management. Besides that, we needed to look over the two critical problem. Researchers assume two critical problems in these refuge strategies. First, the inheritance of the off spring that may be able to have a recessive trait because of chance in breeding between susceptible and resistant insect might occur. Some animals or many factors may transfer one pollen to pollen of these plants. For example, the first generation is between susceptible and resistant have recessive, it will start in infrequent homozygous. Then over time, these plants mate randomly, it emerge the Bt plants with more plentiful homozygous Bt plants which is susceptible that could emerge to non-Bt crops making hybrid offspring that cannot survive Bt plants. Secondly, an assortment mating would cultivate an imbalance amount of homozygous in plantations. This second critical problem is speeding up the evolution of resistance. Diminishing the development of the resistant level, the effect would slower the mortality rate.

If the pests assimilate and adapt them rapidly, this management is most likely to be brief. So it must be enforced to protect each seeds from the transgenic crops vs. non-transgenic crops when these plants grow near areas because these plants might progress and nurture of outcrossing breeding that eventually passing the traits and change the numbers of chromosome of each plants and crops. This implies that in the data and graphs of the researcher's results, it is more current on different toxin genes in same plant may have an interruption start of resistance rather than one toxin plants unrestricted temporally and required a minor refuges.

Annotated Bibliography:

Gahan, Linda J., Fred Gould, and David G. Heckel. "IdentiÞcation of a Gene Associated with Bt Resistance in Heliothis virescens." Science AAAs 293 (2001): 857-61. Print.

In this article, it talks about population of the budworms and other pests in America that have developed resistance in chemical insecticides. This species is the primary target of recently commercialized transgenic Bt cotton, which protects itself from insect damage by producing the insecticidal Cry1Ac toxin. However, farmers must grow Bt cotton are also required to grow a non-Bt cotton refuge from selection, intended to produce a large number of homozygous susceptible. This source is very reliable because the results have been showed. Also, the DNA that had been injected to insects is noticeable that there is specific target. This article is confidential- sort of- because it has good results and it will greatly helped me in my researches on how to manage Bt resistance and the crystal forming inside the insects. I would recommend it to everybody who interest Bt resistance because it says all the topic and it's scholarly and well-written report.

Sewell, Anne. "Monsanto's Bt corn - breeding superbugs & harming human health ."  DigitalHealth, 7 June 2012. Web. 6 Nov. 2012. <>.

The article talks about Bt resistant is now having a problem to the plantation specifically corns. The researchers found out that the pests are becoming a resistant to the material and putting the foods and production at risks. The scientist found out that the strain of Bt resistant is now emerging to the root worms, beetles and other pests. It is now called as superbugs such as the tuberculosis bacteria from our body but the difference is that it occurs to insects. It is superbugs to insects because pests are learning to be resistant to the bacteria and the farmers are having a hard time to find any solutions besides pesticides that could affect the plantations and human health. As the people eat this genetically products, scientist found out it's not anymore healthy because it affects our health. As the article told us that Bt resistant only harm insects but as scientist observed people was affected. The problem can cause from the human health because it has symptoms of gastrointestinal problem and other problems. At the end of the article, it talked about how liver and kidney could be affect by the Bt that is genetically harmed the corn or any plantations.With this article, I do not trust this source because some of the spelling and grammars are wrong which signifies that people will read this kind of article will think it's not presentable and quite distrusting. To get people's attention and to gain trust, I guess that it should always be creative and grammatically and spell check. In addition, there is any scientific proof that tells us that Bt resistant affect humans such as any data to tell if they've eaten a certain kind of corn or any specific location where the corn came from.


In this article, it talks about from the basic and introduction of Bacillus Thuringiensis. Since the topic was by subject, it helps me to comprehend and define some words such as transgenic plants or how the management been workout. The source is very helpful to understand the basic principle of Bacillus Thuringiensis. The source is both popular and scholarly because the information can be seen in accurate materials and it was scholarly due to the concept of their topics and subjects. This article fitted on my research significantly because it gives me the basic idea and new foundation what my research all about. Though I felt it started my research from the beginning, it narrows my research. The only thing it did not help me is the concept of how the plants engineered and the depth of the structures. Furthermore, the resource is reliable because in other articles it also talks about the same material which is very accurate information. However, some data and results showed up recently and this article needed to be updated. For my opinion, the facts are well- documented and it is not biased article because the studies is not been commented that it was awful nor praise by the authors. I personally think that the authors are qualified for this article because it is from well-known university. Their references are also listed at the bottom with their acknowledgements. Also, after the abstract article, the authors started with a little anecdote or philosophy which is interesting start and get the attention of the readers.