T4 Phage Research Paper

8. Eventually the bacteriophages will die in the intestine since there will be no more bacteria to combat and live off of.

Viruses are microscopic particles that invade and take over both eukaryotic and prokaryotic cells. They consist of two structures, which are the nucleic acid and capsid. The nucleic acid contains all genetic material in the form of DNA or RNA, and is enclosed in the capsid, which is the protein coating that helps the virus attach to and penetrate the host cell. In some cases, certain viruses have a membrane surrounding the capsid, called an envelope. This structure allows viruses to become more stealthy and protected. There are two cycles in which a virus can go into: lytic and lysogenic. The lytic cycle consists of the virus attaching to a cell, injecting its DNA, and creating more viruses, which proceed to destroy the host. On the other hand, the lysogenic cycle includes the virus attaching to the cell, injecting its DNA, which combines with the cell’s DNA in order for it to become provirus. Then, the provirus DNA may eventually switch to the lytic cycle and destroy the host.

Some phages infect bacteria to destroy them, which is called lysic lifestyle, while other phages infect bacteria and stay dormant inside them for a while, which is referred to as a lysogenic lifestyle. A phage infects the bacteria cell by injecting its genetic material into the bacteria’s cytoplasm. This allows the bacteria synthesis process to start making the phage’s genetic code instead of its own. Once the bacteria have made enough phages to handle, the walls will break and release all of the phage that was created. The phages that were made are now resetting the process and beginning again by infecting the other near bacteria by injecting their genetic material once again. Those phages that stay within the bacteria and not burst the bacteria will continue to reproduce the phages own genetic code. (Griffiths,

5 drops of chloroform were added to the mixture and incubated at room temperature for 15 minutes to kill, and lyse the bacteria cells which allows all the unadsorbed phages to be accounted for when determining the titer of unadsorbed phage with susceptible bacteria, E. Coli B. (Biology Dept.). 0.1 ml of E.coli B was added to the 10 fold dilution. Using soft agar technique, the unadsorbed phage were plated. After incubation, the titer of unadsorbed phage was determined by counting the number of plaques on the plate from the infection of single E. coli cells in the assay tube by a free phage particle before

Each batch of phage was used to infect a different culture of bacteria. After infection had taken place, each culture was whirled in a blender, removing any remaining phage and phage parts from the outside of the bacterial cells. Finally, the cultures were centrifuged, or spun at high speeds, to separate the bacteria from the phage debris.

Second, the hoc protein found in the capsid of the T4 phage is only tested on agar plates. Although researchers are able to specify exactly what goes into the agar plate and the environment was replicated, the phage may react differently in the body due to other factors such as food consumption or medication usage. If this is true, the symbiotic relationship may still hold true, but there may be differences found on the mucus layers. Third, there may be other proteins that are involved in the phage that contribute to adherence to the mucus layer that were not uncovered in the study. Although the data seen from the hoc protein demonstrates that the hoc protein is involved based on the interaction between the mucin glycoproteins, the research is very specific to the hoc protein and there may be other proteins that are not found in the capsid that are involved in the defense mechanism.

I am applying to the Phage Genomics Research course as I believe it will be a unique experience that will give me the advantage of an early start on my university studies and career aims, as I am aspiring to work as a research scientist in the future. I am particularly interested in the genetics branch of biology, and within that is genomics, so I feel as if this course is perfect as it will allow me to work in the area I hope to continue in. I realize that a similar opportunity may not present itself for another year or two, so I am hoping to take hold of this offer while I can. The prospect of working hands-on in the field so early in my university career is definitely exciting, as well as the chance to contribute to potentially groundbreaking research, and so, I am eager to see where the investigation takes us.

During the lytic and lysogenic cycle, viruses reproduce at a rapid pace resulting in abundant of mutations, thus allowing it to undergo natural selection. Natural selection is the “survival of the fittest” and occurs in viruses mutations that later evolves into evolution. If the mutation is favorable to its environment the virus will continue reproducing with the mutations in order to obtain a higher survival rate. If a virus enters a host cell it is categorized as foreign species and will either go into the lytic or lysogenic cycle. Viruses that enters the lytic cycle (“now or never”) will have a 12 hour time period to reproduce and bust the host cell to infect surrounding cells. Contradicting the lytic cycle, the lysogenic cycle has an

A virus is a noncellular particle containing a genome that can replicate only inside of a cell (Slonczewski and Foster, 2009). It contains an infective nucleic acid, virion, inside a capsid, which is a protective shell made up of proteins. Some virions have a method of transportation to transfer its genome into the host cell. Most often viral gene transfer mediates the evolution of cell genomes. When a virus infects the host cell, the genome of the virus subverts the host cell to make copies of the virus, which then escape to infect more cells (Slonczewski and Foster, 2009). The bacteriophages T4 and X174 were used because the sizes of them simulates a human pathogen, since a human viral pathogen cannot be used. Bacteriophage T4 is used to mimic a Human Immunodeficiency Virus (HIV) and bacteriophage X174 was used to mimic the Hepatitis C virus.

The most widely recognized versatile hereditary components are bacteriophage and bacterial plasmids, which all has a specific technique that takes into consideration exchange between microscopic organisms. Bacteriophages (phages) or bacterial infections appear to have the best effect on staphylococcal differing qualities and advancement. All phages are characterized into one of three particular gatherings: lytic, calm, and interminable. Lytic phages are individuals from the Myoviridae family that have been utilized as a part of phage treatment, since microscopic organisms lyse totally amid arrival of descendants phages. Microbes contaminated with endless phages discharge descendants into the extracellular condition without murdering the host, which permits microorganisms to develop and separate. Mild phages, which are individuals from the Siphoviridae family, shape the most various gathering among all phages. Mild phages can lyse microscopic organisms after contamination, yet they regularly frame a long haul association with the host cell, whereby the phage DNA incorporates into the staphylococcal genome as a prophage . Phages can affect articulation of destructiveness determinants by

Transduction is a method of transferring genes among bacteria via virus particles, which can be divided into two categories known as generalized and specialized transduction. During the lytic cycle, which quickly replicates phages and eventually releases them, ultimately killing the host cell, generalized transduction occurs. In generalized transduction, bacterial DNA is transferred from one cell to another by means of a bacteriophage. The phage first attaches to the bacterial host cell, and releases its nucleic acid in to the host cell, where host DNA is broken down. Phage protein coats (capsids) are formed in the cell, containing not only phage DNA, but mistakenly the bacterial host cells DNA as well. After the newly formed phages are released, the bacterial DNA

Bacteriophages (phages) are viruses that infect and multiply only in bacterial cells. They are not capable of infecting eukaryotic cells (human, animal, fungus, plants and insects). Phages are the natural predators of bacteria. Like all viruses, phages hijack the energy and cellular machinery provided by a host cell to replicate and make viral copies since they do not have their own metabolism. Endolysin enzyme encoded in the bacteriophage genome lyse the peptidoglycan of the bacterial cell wall during the phage lytic cycle, releasing dozens or hundreds of new phages (7). The cycle continues until there are no bacteria left to attack. Since phages only attack specific types of bacteria, they are unlikely to harm any human cells. In addition,

Although I understand the science behind why bacteriophage is an ideal for treatment especially with the increase in antibiotic resistant bacteria, but my concerns are the pro and cons of this type of therapy. Is there a possibility of further infection or even worse will that infection cause a fatal result. According to an article in U.S. National Library of Medicine National Institutes of Health, that clinical trials show promising results, but that the treatments are not completely effective. (Nilsson, 2014) This is due to studies being done with few phages and with limited experimental groups and therapy has limitations. This therapy can only be effective with large amount of groups so that comparisons can be made between he different

The protective capsid helps the virus escape detection and destruction during the invasion of the host. When the virus reaches the target cell, biochemical reactions between the capsid and cell wall allow the virus to latch on and inject its genome into the cell’s interior. Once inside, the viral genetic material insinuates itself into the host’s DNA or RNA. In an efficient feat of natural bioengineering, the host cell’s genetic machinery now does the rest of the work for the virus. The cell, which had already been making copies of its own genome, now also replicates that of the virus. Coded within the viral material is the blueprint for making more copies of the viral genome. Further instructions command the production of capsids and directions for assembly of new viruses. After the host cell becomes engorged with viruses, it explodes, sending the new

Lambda phage, also known as enterobacteria phage λ, is a bacteriophage that infects Escherichia coli. The lambda phage has the capability to reside in the genome of its host through lysogeny or to enter a lytic phase, during which it lyses the cell to produce offspring.[1] The phage consists of a capsid, a tail and tail fibres with the head containing the phage 's double-strand linear DNA genome. The genome contains 48,490 base pairs with 12-base single strand segments at both 5 ' ends. However the cos site circularizes the DNA in the host cytoplasm, therefore in its circular form is 48,502 base pairs in length. The lytic cycle is the life cycle that more commonly occurs after most infections. It begins with the attachment of the phage to the host cell allowing it to inject its DNA into the cell. Following this nucleic acid from the phage is replicated causing the phage 's genes to be expressed which allows for the production of phage proteins. These proteins are then assembled into phage particles which are released when the cell undergoes lysis. This lysis is mediated by genes S, R, Rz and Rz, these genes are shown in the diagram below, which work together to break down the cell wall of the host bacterium. Whilst this mode of