The Discovery Of Restriction Enzymes

Find out more about restriction enzymes by viewing the animation and reading the article listed below.

What was expected that the strains of E. coli that did not have a resistance to ampicillin would not grow. The transformed strain also changed to a blue color when the X-gal was present in plate. The transformed cells also grew because they were free of the ampicillin because they possessed the amp gene that they used as an shield against the ampicillin antibiotic. The transformed cell who turned blue did so because the gene converted the sugar to a blue color but also contained the amp gene to ensure that they grew even when the ampicillin was present. The growth of the colonies on the plates

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 purpose of this experiment was to determine the reversion rate and recombination rate of two mutant T4 bacteriophages, rII 29 and rII 31. Through recombination rate, the map unit between the two mutants was calculated.

Titer of the Bacterial virus, the Measurement of the Recombination and the Reversion Rate, and the Gene Map Distance (Phage Recombination)

The goal of the restriction digests is to be able to cut the plasmids at specific sites. This step

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

How to determine where the restriction enzymes, Ava II and Pvu II, sliced the DNA.

After recognizing the restriction sites, the restriction enzymes cut off the DNA strands at these points, leaving sticky ends on the original DNA fragment. The restriction enzymes can also travel to other cells to cut off DNA sequences, the sequences that can match the bases of the original sequence. The sticky end will find other sticky end to form a new recombined DNA sequence, obeying the law of base-pairing.

The discovery of the gene transfer mechanisms could be attributed by the work of Lederberg and Tatum back in 1946. Using Escherichia coli(E.coli) as their model, they proposed the genetic materia of E.coli could be exhanged via sexual process. In order to prove their hypothesis, they mutated 2 wild type E.coli strains(K12) using X-ray or ultra-violet radiation to produce Y-10 and Y-24 mutant strains. The former was auxotrophic to threonine, leucine and thiamin whereas the latter failed to produce biotin, phenylalanine and cystine[1]. These mutant could only survive in mininal media plates provided that the aforementioned amino acids are supplied accordingly to each mutant strains.

For millions of years’ bacteria have been surviving to their environments and been at war against other microorganism. This wars have lead them to creating an unstoppable arsenal of weapons they can use to survive. Unlike virus that need a host cell to survive, bacteria can survive anywhere since they can share their DNA with each other. This allows bacteria to survive in places like radioactive waste, zero oxygen environments, and even in absolute darkness. Unlike human beings who are born with a specific genetic code, bacteria have the capability of changing that code. Bacteria have three methods of evolving themselves in order to survive the harsh is of conditions. The three methods are called horizontal gene transfer. The first is Transformation, but some pathologists call it the “Funeral Grab”.

A restriction enzyme is an enzyme that acts as a catalyst that can cut a strand of DNA in a particular place.

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

Did you know that with the science of DNA manipulation, animal cadavers can be turned into insulin for diabetics? Back in the 80's scientists isolated the human gene for insulin and transferred it into bacteria. Now bacteria cultures are used to produce large amounts of human insulin. DNA manipulation is especially important in medicine, where it holds the hope of curing genetic diseases such as Huntington's, and even some types of cancer. There are several major types of DNA-manipulation enzymes used by living cells. The first type is DNA polymerase, which cells use to replicate their own DNA. The next type is DNA ligase, which joins 2 pieces of DNA to create a single piece. The third type is restriction enzymes, which appear to be made only by bacteria. Restriction enzymes are very important enzymes that are vital to our manipulation of DNA (Rapoza, DNA, 2).

Plasmid DNA with Restriction Digest: The purpose of restriction digest of plasmid DNA is to understand how each DNA plasmids was cut with the given restriction enzymes and perform gel electrophoresis to observe the samples. Nine restriction digests were created, containing three digests for each of the three plasmid DNAs identifying as recombinant, non-recombinant, and unknown. Out of the nine digests, six are actual digests and three are undigested controls. A master mix is created to add to each of the nine samples with its following stock ingredients: 10 ul of 2X Reaction Buffer, 1 ul of Nco1, X ul of sterile water (Single digest), 10 ul of 2X Reaction Buffer, 10 ul plasmid DNA, 1 ul Nco1, 1 ul of Not1, and X ul of sterile water (Double