Restriction Site Mapping Of Λ Phage Dna

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,

The titer of recombinant phage was determined with the number of plaques on the E.coli K plates and the titer of total phage progeny was determined with the number of plaque on the E.coli B plates.

The main objectives of this experiment included making dilutions of solutions, plating phage or bacteria, and determining the number of bacterial viruses or phage in a suspension. It was also conducted to demonstrate that two different mutants of phage T4 can exchange genetic material to give rise to wild-type phage. The experiment was used to distinguish mutants from wild-type by their host specificity. The recombination in bacteriophage was performed to determine the concentration of unadsorbed phage from the U series plates, total concentration from B series, and concentration of

This project is all about isolating bacteriophage in soil. They come in different sizes and shapes, each to their own unique look. Phages have a protective protein head that contains DNA and a hollow tube tails (http://phages.org/bacteriophage/). Since bacteriophage cannot reproduce and replicate themselves, they need a host to do the work for

The focus of this lab was to identify which plasmid (PFG or Pglo) was inserted into the E. coli culture. In order for the E. coli to be transformed, the E.coli must first be made competent. The cells were made competent by incubating the cells in calcium (2+) and then in cold temperatures. A quick heat shot opens pores in the cell membrane and allowed plasmid DNA to enter the cells. The plasmid that was inserted into the E. coli culture had antibiotic-reistance gene and a reporter gene. A reporter gene is a gene that is easy to detect, and for this lab it could be Pglo or PFG. The cells were placed in plates that contained antibiotics to kill any bacteria that did not uptake the plasmid, this is necciary because about 1% of bacteria will be transformed. This allowed only cells that up took the DNA to

It is a lattice made from the white blood cell's own DNA and studded with small toxic enzymes that chemically strike and digest the trapped pathogen.

The purpose of the experiment was to isolate plasmid DNA, followed by restriction digestion using restriction endonucleases and then visualizing the digested fragments after subjecting to gel electrophoresis. Plasmid DNA (pSP72 DNA) was isolated from Escherichia coli KAM32 (E.coli) cultures using the QIA prep miniprep kit and then subjected to restriction digestion by EcoRI and HindIII. The restriction digested DNA was then loaded into the wells of 0.7% agarose gel and subjected to electrophoresis. It can be concluded from our results that our plasmid DNA isolation was successful and the restriction digestion results were partially in agreement with our hypothesis.

Stage one the DNA in the pathogens is first transcribed into RNA so that is can be used, as a single strand is needed. Then the pathogens are lysed to expose the nucleic acids and a specific oligonucleotide hydrolyses to the

There are phages in everything we touch, eat, and drink. Since phages are ingested, they are found in the gut, mucous membrane, basically all over our body. About every two days, bacteria on earth are eliminated by bacteriophages as they constantly keep killing bacteria when they grow out. Bacteriophages were first discovered about 100 years ago; antibiotics did not exist, so then bacteriophages were used to kill bacteria. Later on, antibiotics came to be known and dropped the use of bacteriophages to just controlling infections and started using antibiotics more. Phages may seem like a phenomenon virus, but it has its obstacles. To use phages, people need to use “a cocktail of phages to kill a single organism.” Complex mixtures could potentially have difficulties getting FDA approval because bacteriophages lift DNA from bacteria so that the FDA could know that DNA they are picking up. There

Vibrio cholerae is a "comma" shaped Gram-negative bacteria with a single, polar flagellum for movement. There are numerous strains of V. cholerae, some of which are pathogenic and some of which are not. V. cholerae is a facultative anaerobic organism and was first isolated as the cause of cholera by an Italian anatomist Filippo Pacini in 1854, but his discovery was not widely known until Robert Koch, working independently 30 years later, publicized the knowledge and the means of fighting the disease. The entire genome contains two circular chromosomes. Chromosome 1 has 2.961.149 base pairs with 2.770 open reading frames and chromosome 2 has 1.072.315 base pairs, with 1.115 open reading frames. It is the larger first chromosome that contains the crucial genes for toxicity, regulation of toxicity and important cellular functions, such as transcription and translation.The second chromosome is determined to be different from a plasmid or megaplasmid due to the inclusion of housekeeping and other essential genes in the genome, including essential genes for metabolism, heat-shock proteins and 16S rRNA genes, which are ribosomal sub-unit genes used to track evolutionary relationships between bacteria. Also relevant in determining if the replicon is a chromosome is whether it represents a significant percentage of the genome, and chromosome 2 is 40% by size of the entire genom.(fig 1)

The T4 phage is a virus that belongs to the bacteriophage family. These viruses utilize bacterial cells as a host for replication. Bacteriophages are bacterial viruses and have been studied for many years. The T4 is a morphologically complex virus with a particularly intriguing shape featuring distinct

There are two phospholipases involved in virulence of Lm including phospholipase PlcA encoded by plcA (Mengaud et al., 1991) and phospholipase PlcB encoded by plcB (Vazquez-Boland et al., 1992). It has been demonstrated that PlcA and LLO are important in the lysis of single-membrane vacuoles whereas PlcB and LLO are required to destroy double-membrane vacuoles (Mengaud et al., 1991; Vazquez-Boland et al.,

The bacteria used in this question involved a chloramphenicol resistant S. typhimurium as the donor cell, and a chloramphenicol sensitive S. typhimurium as the donor cell as well as P22 phage. Using an overnight culture of resistant S. typhimurium, a P22 lysate was prepared. During the course of the experiment, two titers of the sensitive S. typhimurium were prepared using dilutions of 10-6, 10-7, 10-8, and 10-9 for the 1st day, and 10-7, 10-8, and 10-9 on LB plates for the final titration to find the CFU/mL for calculations. A titer for the P22 phage was also prepared (with S. typhimurium) using dilutions 10-7, 10-8, and 10-9 on LB plates. This information was used to determine the amount of phage needed for the transduction process, which

Type-II toxin-antitoxin (TA) systems are a relatively ubiquitous feature of prokaryotic genomes (1), consisting of a ribonucleolytic toxin and a labile antitoxin. Under normal conditions, the toxin is silenced by pairing with its cognate antitoxin, but can impact cell physiology in several ways when the antitoxin is removed through proteolytic degradation. TA systems were first identified as assisting in plasmid maintenance via post-segregational killing (2,3), as well as in phage exclusion, where expression of the toxin sacrifices some infected cells to preserve the larger population (4). Subsequently, the identification of chromosomal TA systems led to a re-evaluation of their physiological significance, including their potential role in various stress response mechanisms (5) and stochastic persistence (particularly of pathogens) (6).