The Viability of Escherichia Coli to Gain Resistance from Ampicillin
BIOSCI 152 SLIME MOLD EXPERIMENT - REPORT GUIDELINES AND GRADING RUBRIC
Assignment Learning Objectives and General Reminders
• The objective of this assignment is for you to plan, carry out and analyze an experiment and write it up in scientific style using formatting and formal scientific language
• This is an individual exercise – you need to write your own work from your own understanding, not just paraphrasing sources. Plagiarism will not be tolerated (and plagiarized assignments will receive zero).
• Does your report consist of well-organized paragraphs (i.e., clear topic sentence, one idea per
paragraph)?
• Have you proof-read your report to check for errors of grammar and spelling?
• Your report needs to follow the rules for Scientific writing as indicated in the PowerPoint “Scientific Writing”, organized clearly with subheadings for each of the sections: Title, Introduction, Materials and Methods, Results, Discussion, Literature Cited. See also Lab 1 Scientific Writing powerpoint pdf on D2L, for details. See formatting and detailed requirements below:
1. Title
• The title should be informative, conveying something about what you investigated, and include the correctly written scientific name of the organism
• On your title page, also include your name, your lab section # and the date submitted
2. Introduction:
• This where you provide relevant background to slime mold and examining growth and should be long enough to adequately introduce the topic but not more than 25% of the report?
• You need to have a clear statement of the purpose of the experiment
• You need to clearly state the hypothesis and predictions
• Clearly state the control and variables (independent, dependent, and standardized)
• All supporting information from the literature needs to acknowledge the source with a citation, using correct format for in-text citations (Author/s, year) – see Lab 1 Scientific Writing powerpoint
3. Methods:
• Describe what you did in sequential, detailed manner, clearly enough for someone to be able to
repeat the experiment, including which conditions were the same and which were different for control and experimental treatments
• Methods should be written in past tense
• Include specific sample sizes used, exact incubation times, and organisms used, with correct
scientific names, terminology and units (use only metric units)
• Do not copy the lab manual word for word but describe what you did in your own words. When
general ideas or principles came from the lab manual, restate in your own words but also correctly
cite the lab manual as the source
4. Results:
• You need to include a text description of your qualitative observations and comparisons
• Include a clearly labelled graph (constructed in excel) of the growth of your organism based on the
measurements (see details and example figure below)
• Include calculations of growth rate for the experiment (see below) as part of your comparisons
• When you describe something shown in the graph in the Results text, refer to the figure e.g. “The experimental treatment started growing faster than the control (Figure 1)”
• Do not include any interpretation of the results (leave for the Discussion) - describe only that was measured or observed
5. Discussion:
• Address statements of hypothesis and predictions from the Introduction - clearly state whether the results supported or refuted the hypothesis and why
• State the significance of the results in terms of what may promote or inhibit growth of the organism
• State how your results relate to similar studies and what is known about the subject
• If applicable, speculate reasonably why the experiment didn’t work and how you might improve the
experimental design or measurements
• Link your conclusions back to the background about slime mold growth from the Introduction
• Include correctly-formatted citations for all supporting information from the literature Area covered
6. Literature Cited:
• Include a complete ‘Literature Cited’ section including lab manual citation:
[Sandgren C, P Engevold and S Hoot. 2013. BIO SCI 152 Laboratory 4: Life cycles: Survey of Fungi,
Protists and Algae Diversity. Available on D2L.]
• You should have a minimum of 3 outside references, with at least 2 from the published scientific
literature. No websites can be included as sources. Do not include hyperlinks to journal articles
• Include all the references cited in the text, and do not include references that you do not cite in the text
• Use a consistent and correct reference formatting (see Lab 1 Scientific Writing powerpoint pdf, and
‘SAMPLE ARTICLE FROM ECOLOGY JOURNAL’ on D2L (in Content, ‘Writing Help and Report Grading Rubrics’))
The Viability of Escherichia Coli to Gain Resistance from Ampicillin
through Gene Transfer
Xiaoyang Han
BioSci 152, Section 809, Group 3
Gene Transfer Report
INTRODUCTION
Your day goes from typing on your keyboard or swiping on your smartphones but did you think you are safe? Those keyboards and smartphones are teeming with bacteria. Probably most of them are harmless but we could never be sure. It is very important to wash your hands after whatever you have done as bacteria can be easily transferred everywhere. It can be transferred from your surroundings to your hands, and from your hands to your food. Red flags are up when bacteria are transferred to food as these are often the cause of diseases. The Bacteria that can cause diseases are called pathogenic bacteria (“E. Coli (Escherichia Coli)”, n. d.). There are a lot of pathogenic bacteria. One of the most common pathogenic bacteria that can cause a disease is Escherichia Coli. This organism which was named after its discoverer, Theodor Echerich, is a facultative anaerobic bacterium which is gram negative and has rod shape (Lim, et al., 2010). Most of its types are harmless as these usually live in the intestines of both humans and animals (Lim, et al., 2010). Yet, there are also harmful types which are pathogenic. These types of pathogenic E. coli bacteria can be ingested through contaminated food such as raw or undercooked meat, raw vegetables and fruits, unpasteurized milk, and dairy products made from it (Lim, et al., 2010). You can also get it through drinking or swimming in a contaminated water (Lim, et al., 2010). These can also be acquired when you are in contact with contaminated animals as well as feces of people infected with it (Lim, et al., 2010). The Center for Disease Control identified six pathogenic types that can cause diarrhea, respiratory illness and pneumonia, urinary tract infections and etc. (“E. Coli (Escherichia Coli)”, n. d.). These pathogenic bacteria cause an estimated infection of around 265,000 per year in the United States (“E. Coli (Escherichia Coli)”, n. d.). For Thousands of years, men have searched for ways to combat diseases. In the ancient times, they used plants, moldy bread, honey, and even animal feces to treat infections (Gould, 2016). A lot of Scientists have already found ways to make medicines that are the precursor to antibiotics but most notable of them all was the accidental discovery of Alexander Fleming of the use of penicillin which really paved way for the production of modern antibiotics (Gould, 2016). This also resulted to more studies conducted to try and understand microbes better thus, about 70 years ago, experimental microbial genetics emerged (Arber). In this, Darwin’s Theory of Evolution has again been confirmed when they recognized a problem that some bacteria have eventually developed resistance to modern antibiotics. As the problem continually increased, there was already a need to identify the cause (Arber, 2014). The scientist found out that the cause of bacteria having resistance to antibiotics was horizontal gene transfer (Arber, 2014). The resistant gene can be transferred from one bacteria to another by horizontal gene transfer in three ways namely, transformation, transduction, and conjugation (Burmeister, 2015). When bacteria get DNA from its surrounding environment then this is characterized as Transformation (Burmeister, 2015). Conjugation, on the other hand, involves a direct transfer of genes from one bacterium to another (Burmeister, 2015). Finally, Transduction happens when transfer of bacterial DNA from one bacterium to another is done through a virus vector (Burmeister, 2015). It is a little alarming and scary to think that there might come a time that most bacteria will already be resistant to antibiotics. This means that it will be harder for us to treat the diseases they have caused. Thus, it is important for researchers to dig deeper into this topic to be able to counteract and find a solution to resolve the issue before it escalates. In line with these, this paper will try to understand how gene transfer in bacteria such as Escherichia Coli happens. This paper will specifically understand gene transfer through bacterial transformation. The E. coli bacteria will be able to gain resistance from Ampicillin through gene transfer using the method of transformation. If an Ampicillin resistant gene be added to Echerichia Coli bacteria through the method of transformation, then the E. Coli bacteria will become resistant to Ampicillin. This paper will also determine if the hypotheses above is indeed viable.
METHODS
The process used in understanding bacterial transformation in Escherichia Coli was from the method of BioSci 152 Laboratory 2: Gene transfer in Escherichia Coli. The class was divided into 6 groups. Each of the group was given the same materials to perform the same experiment. Safety and precaution were observed by all groups when these procedures were conducted. The experiment started with two separate microtubes. Each of these tubes was labeled as #1 and #2. Each tube also contained transformation-competent E. coli cells. The control tube was tube #1 and it was the tube without the plasmid. The experimental tube was tube #2 where a 5 µL of plasmid DNA (pGFP) was aliquoted. Both tubes were incubated on ice for 20 minutes and the bottom was gently flicked to ensure that it will be completely mixed. Four Petri plates were then prepared while the tubes were incubating. The first two plates were labeled A & B and only contained LB Agar. The last two plates were labeled as C & D and they contained LB agar plus ampicillin. All four plates were also labeled with the group name and lab section number. After 20 minutes of incubation, the tubes were transferred to a 42°C water bath for 1 minute. Then the tubes were removed from the water bath and were immediately placed on ice for 2 minutes. 500 µL of NZY recovery medium was pipetted to each tube of cells and the tubes were incubated in a 37°C for 60 minutes. Then 100 µL of cells from tube #1 were pippeted to petri dish A & C and 100 µL of cells from tube #2 were pi...