Escherichia coli O157:H7

The first step in phage infection is the attachment of the phage to the host cell surface. This is typically accomplished by the recognition of a receptor on the outside of the bacterial cell wall such as an antigen, pilus or other structure. There is much variability from phage to phage in terms of which receptor they bind to. Bacteriophage can generally be classified into two categories, lysogenic and lytic (virulent) (Fig 6). The choice between the lytic and lysogenic cycle depends on the…

S. aureus was first isolated by Alexander Ogston. Ogston described the bacteria, which he isolated from pus collected from surgical wounds, as micrococci (Thomer et al., 2015). This description was given because of the sphere-shape of the bacteria and the grape-like clusters that they form. After Ogston’s discovery, Friedrich Rosenbach differentiated between two staphylococci bacteria, which were isolated from humans (Thomer et al., 2015). These bacteria were named S. aureus and S. albus. This…

The oldest forms of life are single-celled organisms known as microbes. There are many different types of microbes that are found all around the world, and they play an important role in the environment, in the body of animals, and even in the health of plants. The specific type of microbe investigated in this paper is the gram positive bacterium known as Kocuria rhizophila, which has a bright yellow color that simplifies identification. The main objectives of the paper are the following:…

In 1969, Thomas Brock and Hudson Freeze of Indiana University discovered a new bacteria species in the Yellow Stone Park, that scientist thought it could not survive above 55 degrees Celsius. Thermus aquaticus is a typical gram-negative bacterium, meaning that its cell walls contain much less peptidoglycan and unlike gram-positive bacteria, gram-negative bacteria contain lipoproteins. T. aquaticus appears as either a rod or short filaments. When exposed to sunlight, it can exhibit a yellow, pink…

Bacteria They are formed by a single rudimentary cell. They have no nucleus or plastids, but chromatin. Some have assimilators pigments. They are on earth, water, and air, and can generally move. They may be causing disease and therefore are called pathogens. Those that do not cause disease are called saprophytes. In some cases, they are even useful, as in digestive processes or synthesis of vitamins. By the way, they are called coconuts when circular; bacilli if they have the form of rods;…

Many living organisms rely on the environment for essential resources, including water, food, and shelter. However, they not only need the help of the environment but also other species that live within the biosphere. This lab aided in demonstrating how the affect of one organism has on another, and whether or not it benefits either organisms or one organism. In order to progress with the experiment we first have to identify our variables that will be used during the experiment. The independent…

The endospore is a quiescent and tough structure that is form by some gram-positive bacteria that allows them to survive in harsh and extreme environments. Because only some genera of bacteria produces the endospore, its identification is important in helping us identify some bacteria. 2. What type of eukaryotic cells did we observe and how were they different from the prokaryotes we have looked at? (Be sure to include ways they are different internally as well as any observable traits) The…

Illustration of sexduction in E. coli using streptomycin resistant F-lac- recipients and F′lac+ donors Abstract The process in which DNA from a donor cell is transferred through physical contact into a recipient cell is known as conjugation. In the experiment, sexduction, a cross between F′ and F- plasmids, was demonstrated by mixing the donor and recipient, diluting them and using selective plating methods. The plasmids from the donor, recipient and transconjugant were isolated and analyzed…

In 1906 Mary Mallon was employed as a cook for a wealthy banker that resided in New York. Six out of 11 residents in the banker’s household developed typhoid fever. As a result of this, a sanitary engineer known as George Sober, quickly questioned the ill group of people, including Mary Mallon who had exhibited a less intense form of the disease. Mr. Sober first concluded that the infection was the result from freshwater clams; however, Mary Mallon was the host for the bacteria. She continued to…

Genetic transformation is an important method, in molecular biology and genetic engineering, for transferring DNA amongst a variety of organisms. In Lab five, my lab partners and I used calcium chloride to make the bacterium cell walls more permeable and a heat shocking method to introduce the pGLO plasmid in the E.coli bacterium so that they may exhibit ampicillin resistance. The Goal of the experiment was to observe whether or not, given one of the four specific conditions, the pGLO plasmid…