UF iGEM 2021


The Global Antibiotic Resistance Crisis


Antibiotic resistance is an increasingly prominent issue whose severe effects can be observed in several areas ranging from healthcare to food production. According to a 2019 report by the Center for Disease Control, more than 2.8 million antibiotic-resistant infections occur in the U.S. each year, and more than 35,000 people die as a result (2021). Globally, antibiotic resistance results in 700,000 deaths each year. This number is expected to rise to 10 million by 2050.

Financial Burden

Treatment courses for illnesses caused by antibiotic resistant bacteria often require prolonged use of various drug combinations. This places further financial burden on patients suffering from infections such as tuberculosis and pneumonia. The CDC also reports antibiotic resistance adds a 20 billion dollar surplus in direct healthcare costs in the United States, which is exclusive of about 35 billion dollars in loss of productivity annually (Dadgostar, 2019).

Healthcare Impact

In addition to the massive cost of life and finances, antibiotic resistance contributes to complications in particularly vulnerable patients such as those undergoing chemotherapy or those with chronic conditions. While in the hospital 5–15% of all patients acquire healthcare associated infections sustained by multidrug-resistant bacteria, rendering the therapeutic approach very difficult (Monegro, 2020).

Industrial & Environmental Impact

The USDA estimates 80% of all antibiotics produced in the U.S. are used in food animal production (Food and Drug Administration, 2015). In factory farm settings, antibiotics play a crucial role in allowing high volumes of animals to be raised in close confinement without the risk of disease outbreak. Strains of bacteria found in both humans and animals (such as E. coli and S. aureus) with the capacity to exchange resistant traits pose an especially heightened risk to consumers.

Our Solution

Team UFlorida has decided to tackle the crisis of antimicrobial resistance in two parts: creating alternative selectable markers to antibiotic resistance genes, and utilizing the DNA nuclease activity of the cas9 protein to specifically target and cut antibiotic resistance genes.

Alternative Selectable Markers

Selectable markers are genes, often antibiotic resistance genes, that are introduced into a bacteria in order to serve in artificial selection. For example, when scientists want to give DNA to a bacteria, the DNA is also often genetically modified to include antibiotic resistance genes. Bacteria that have taken up the DNA of interest, along with the antibiotic resistance genes, will survive when plated on the corresponding antibiotic, while those that have not taken up the gene of interest will not survive.

Organisms modified to include antibiotic resistance genes are not permitted to be released from the lab because they may further confer antibiotic resistance to the environment. Due to these constraints, team UFlorida has decided to create alternative selectable markers that do not rely on antibiotic resistance genes so that their use can be expanded beyond the lab without the consideration of spreading antimicrobial resistance. We will be creating selection markers using metabolic genes that give bacteria the ability to metabolize sugars that it would otherwise not be able to. We are interested in testing the following sugars: sucrose, arabitol, and ribitol.

Conjugation/CRISPR System

Team UFlorida is also developing a two plasmid system that will deliver the DNA nuclease activity of the cas9 protein to a pathogenic, antibiotic resistant bacteria. The system will consist of a delivery bacteria, and a recipient bacteria: the delivery bacteria will contain a conjugative plasmid and a plasmid with CRISPR genes on it, and the recipient bacteria will be the pathogenic, antibiotic resistant bacteria. The intent is that the delivery bacteria will be able to engage in conjugation with the recipient bacteria and deliver the CRISPR components. After the CRISPR genes are introduced to the recipient bacteria, it will begin producing CRISPR proteins, which will target the bacterial chromosome, thereby cutting and killing the pathogenic bacteria. Our plan is to allow this system to be tested in a lab through the use of our alternative selectable markers.


Center of Disease Control. (2021, March 2). Biggest Threats and Data. Centers for Disease Control and Prevention. Retrieved October 10, 2021, from
Dadgostar, P. (2019, December 20). Antimicrobial resistance: Implications and costs. Infection and drug resistance. Retrieved October 10, 2021, from
Monegro, A. F. (2020, September 3). Hospital acquired infections. StatPearls [Internet]. Retrieved October 10, 2021, from
Food and Drug Administration. (2015, December). Summary Report on Antimicrobials Sold or Distributed for Use in Food-Producing Animals. Retrieved October 10, 2021, from