Escherichia Cli and Bacillus Subtilis

For the methods used in this experiment refer to the following from UFV BIO 202 Lab #2: Investigation of Heat Shock Protein Gene Expression using Western Blotting (2017).

Escherichia Coli, located in one of the main organs known as the large intestine, is a type of bacteria that helps digestion. (Trzepacz, Timmons, and Duobinis-Gray, 2016) For Escherichia Coli to remain stable and alive, it needs specific necessities. These needs are known as the following: Energy, vitamins, and similar compounds. Escherichia Coli is found everywhere!

These organisms use several adaptations in order to survive high temperatures. They are prokaryotes, which more easily adapt to extreme temperatures than eukaryotes. They use salts such as potassium and magnesium to protect their DNA from degradation, and they generate special polyamines that help to protect the proteins in their DNA from being degraded in high temperatures. One adaptation that thermophilic archaea have that helps them to survive high temperatures is ether bonds in their cell membranes, which are more stable than bonds found in many other

For this experiment, a non-virulent strain of Escherichia coli was used to illustrate differences in growth rates for different temperatures. The culture was created by placing 35.0 ml of L-Broth into a 125 ml flask and adding 0.025 ml of an overnight bacteria culture. This culture mixture was divided and placed into 3 shaking incubators that were kept at 25˚C, 30˚C, or 37˚C (Timmons 2004).

Bile has bile salts, or in other words, bile acids in it. Previous studies of fish, whose bile should remain the same no matter what they eat, have shown that there were changes in the bile salt synthetic pathway. The original bile salt synthetic pathway was thin and very simple. Over many generations, it has become longer

While thermal vents and hot springs are considered to be some of the most extreme environments on Earth, several organisms are able to thrive in these hostile locations where most life would perish. Among these are thermophiles and hyperthermophiles. While the two share similar adaptations to survive in these extremes, they differ in their temperature growth optimum. Hyperthermophiles can grow optimally up to 105°C, whereas thermophiles are classified as growing between 50°C and 70°C. At such extreme temperatures, proteins lacking the necessary adaptations undergo irreversible unfolding, exposing the hydrophobic cores, which causes aggregation . Thermophilic proteins have several adaptations that give the protein the ability

Bacteria can thrive in many ways. Its growth can be influenced by temperature, pH level, water activity, supplemental compounds, absent of carbon dioxide, presence of sulfur or nitrogen, oxygen, and a supply of nutrients, or it could have a spontaneous generation. A spontaneous generation is the supposed production of living organisms from nonliving matter (Rogers & Kadner, 2015), as inferred from the apparent appearance of life in some supposedly sterile environments. There are three different cardinal temperatures at which the cardinal temperatures can be affected : minimum, optimum, and maximum. Temperatures above or under the maximum growth temperatures for a bacterial cell could result in an irreversible denaturation of enzymes, or in other cell structures, which

Purpose: To determine the effects of temperature stress on the extent of cell membrane damage.

Bacteria of the Bacillus genus are known to be rod shaped and are usually motile. They are endospore-forming and obligate aerobes, which means that these cells need oxygen to live. Bacillus are Gram-variable. They all begin as Gram positive; however, after time and aging of these cells, there is a decrease in peptidoglycan which is why they are considered gram variable. These cells can be arranged in a variety of different ways, including chains, pairs, and singles. The Bacillus genus consists of approximately 370 different species (Priest et al., 1988). However, of all those 370 species, the only two that are pathogenic to humans are Bacillus anthracis and Bacillus cereus. Not only does the Bacillus genus affect humans, but there are some

According to the results of the experiment located on Image 1 in the results section, the phenotype of the E Coli demonstrated a change when exposed to the plasmid pGlo. This conclusion disproved the hypothesis. All four agar plates were exposed to LB broth (Luria broth). This broth is the source of food and nutrients E Coli used to grow and divide. As demonstrated by Image 1, there was growth in the in the agar plates -LB, +LB/amp, and +LB/amp/arab. The substantial growth that was demonstrated in the -LB agar plate (estimated at 75-80% growth) was due to this was the standard E Coli without any ampicillin or pGlo present. Moreover, the agar plate for +LB/amp showed a margin of growth. The percentage of growth was estimated at a 45-50% growth and signified this in individual colonies. This plate contained the plasmid pGlo. This plasmid is coded with GFP protein, antibiotic resistance gene, and the araC gene (www.bio-rad.com). Even though the agar plate contained the antibiotic ampicillin which kills the E Coli bacteria, the E Coli still grew because the plasmid pGLO was present. This growth demonstrated that the E Coli bacteria absorbed the pGLO plasmid and revealed a change in the E Coli’s phenotype. There was a margin of growth because the E Coli was subjected to the transformation solution (CaCl2) and the heat shock. A

Chilly adjusted (psychrophilic and psychrotrophic) microorganisms are recognized from mesophiles which their capacity to develop at low temperatures. They are generally conveyed in nature. Their reaction to high temperatures was demonstrated to be disturbance in protein union by failure of RNA development, modifications of the structure of nucleic acids, inactivation of thermo labile catalysts, enactment of lytic chemicals, changes of the cell morphology, hindrance of cell division and instigation of warmth stun proteins. At low temperatures, among other physiological attributes, psychrophiles and psychrotrophs have slower metabolic rates and higher synergist efficiencies than mesophiles. The Cold-adjusted microorganisms have a significant

Several studies have revealed pathogen specific responses to bile that alter the expression of virulence factors. When V. cholerae was grown in the presence of bile, expression of the essential virulence genes ctxAB and tcpA was drastically repressed [30]. Since bile is a heterogeneous mixture, crude bile was fractionated, and the components that mediate virulence gene repression were identified. It was shown that unsaturated fatty acids (UFAs) present in bile, arachidonic, linoleic, and oleic acids were responsible for repression of ctxAB and tcpA genes [31]. However, expression of toxT encoding the direct transcriptional activator of ctxAB and tcpA was not affected and ToxT protein levels were similar between V. cholerae grown in the presence or absence of bile or UFAs [31]. Subsequently, the crystal structure of ToxT revealed that unsaturated fatty acids can bind to ToxT and keeps ToxT in a ‘closed’ conformation that is not capable of binding DNA [32]. Hence ToxT cannot activate expression of ctxAB and tcpA in the presence of bile or UFAs and the genes continue to be repressed by H-NS [33]. Bile also causes drastic repression of virulence genes in salmonellae. Salmonellae grown in the presence of bile demonstrated a marked

The temperature range for any one bacterial species is characterized by its cardinal temperatures - otherwise known as the minimum, maximum, and optimal temperatures that the bacteria will grow at. There are varying degrees of classification that categorize bacteria some of which include bacteria that grow optimally at cooler temperatures while others at higher more extreme temperatures. For example, psychrophiles categorize organisms that grow only below 20 degrees Celsius, whereas bacteria growing in the range of 65 to 110 degrees Celsius are called extreme thermophiles. However, with the exception of extreme thermophiles, many bacteria are generally intolerant in environments encompassing higher temperatures. When bacterial cells are subjected to such temperatures, different components of the bacterial cell including phospholipids, nucleic acids, and proteins become denatured resulting in the disruption of tertiary structures (Nadwell 1999). Four bacteria including, E. coli, B. subtilis, B. stearothermophilus, and M. cryophilus were subjected to varying temperatures in order to determine the cardinal temperatures of each individual species. In regards to thermal death time (TDT), or the time it takes to kill a population of organisms at a specific temperature, as well as the decimal reduction value (D-value), or the time required in

The purpose of the two experiments was to determine the fundamental effects that temperature has on the growth and survival of bacteria. During the first experiment five different bacterial broth cultures of Escherichia coli, Pseudomonas fluorescens, Enterococcus faecalis, Bacillus subtilis and Bacillus stearothermophilus were individually incubated at temperatures of 5, 25, 37, 45 and 55°C for one week in an aim to distinguish the effect temperature has on growth and survival of the five different species. After one week they were observed for distinguishable changes by the turbidity showing an indication of bacterial growth, or the clarity an indication of no survival.

These strains of bacteria have the capacity to transform sugars to acetic acid directly without creating ethanol as an intermediate (Jia et al., 2007).