Biology & Genetics
Kyara Crespo Gutierrez, Kyara.CrespoGutierrez@unh.edu
University of New Hampshire, with Dr. Feixia Chu
Epigenetics, Proteomics, Mass Spectrometry
Determining the Effects of Acetylation and Deacetylation of H3K56 on Embryonic Stem Cell Stemness
With the newer tool that is the epigenetic field, significant stem cell research currently focuses on the influence of epigenetic markings, such as acetylation— the addition of “a small molecule made of two carbon, three hydrogen, and one oxygen atoms,” to DNA— or lack thereof, on the genetic coding of these cells (National Cancer Institute). The proposed research deals with histone proteins, proteins around which DNA is wrapped, and the specific amino acid lysine, which is positively charged. The purpose is to further understand the consequences of acetylation of the 56th lysine on histone protein H3 regarding stemness of cells, that is the ability to differentiate into any type of cell and to multiply indefinitely. Cells that have an altered genome to emulate acetylated and unacetylated 56th lysine on H3) will be analyzed utilizing mCherrytagging, MNase digestion, SDS-PAGE, and LS-MS coupled with online databases. The analysis will be focused on the difference of protein composition and histone modification of each type of cell. The expected outcome will be for unacetylated mutants to have a lower concentration of other proteins that are related to stemness, such as Oct4, SOX2, and NANOG, indicating that the acetylation of H3K56 may play a fundamental role in maintaining stem cell qualities. (Swain et al., 2020). The proposed research will be helpful for further experiments done on stem cells, embryonic, cancer, or induced, and could potentially lead to breakthroughs in cancer therapy by either proving or disproving a connection between H3K56ac and cell stemness.
Aaliyah Gutierrez-Cano, agutie42@stedwards.edu
St. Edward's University, with Dr. Claire Edwards
Biology
Producing Ethanol Tolerant Mutants of Saccharomyces cerevisiae 09-448 using a UV Mutagenesis Protocol
The collapse of numerous ecosystems as a result of climate change prompts society to
stop using fossil fuels as an energy source and, instead, use alternative fuels, like biofuels that are made from the fermentation of biomass, such as pectin-rich biomass. Although the fermentation of pectin-rich biomass is costly, the overall process can be made more inexpensive with the use of Saccharomyces cerevisiae 09-448, a yeast strain that produces its own pectinase and obviates the need for some commercial enzymes that are used to catalyze the breakdown of polysaccharides found in the cell wall of pectin-rich biomass into monosaccharides for yeast to ferment. However, 09-448 cannot yet be used industrially because it cannot withstand common industrial stressors, such as increased ethanol concentration, temperature, osmotic pressures, and changing pH conditions. To produce an ethanol-resistant mutant capable of surviving under fermentation conditions, 09-448 was exposed to UV radiation for up to three minutes. Potential mutants were then screened for ethanol resistance by measuring their growth with a plate reader in ethanol concentrations up to 6%. Of all 12 mutants that were screened, eight performed better than 09-448 at both 4% and 6% ethanol concentrations. Mutant 12 seemed the most promising with a final OD of 1.15 au and a minimum generation time of 65 minutes compared to the wild type with a final OD of 0.633 au and a minimum generation time of 70 minutes when grown at an ethanol concentration of 6%.
Raquel Guerrero, raquel_guerrero1@baylor.edu
Baylor University, with Dr. Chris Kearney
Microbiology
Repurposing of naturally-derived VK-13 antimicrobial peptide using SUMO cloning vector
Traditional antimicrobials have facilitated the development of drug-resistant bacteria, indicating a need for alternatives. Antimicrobial peptides were discovered in the 1990s and are a promising next step against super-bacteria. AMPs can inactivate pathogens by disrupting bacterial cell membranes as well as modulating immune responses. AMPs can be developed to minimize dysbiosis and harm done to the host microbiome, which is an important component of antimicrobial development. I hypothesize that the effectiveness of the AMP VK-13 can be improved by fusing it to a carrier protein, termed SUMO, which is able to detoxify and produce the AMP. AMP genes and primers were outsourced and used to create ligation-independent staggered ends via polymerase chain reactions. Annealing enabled the AMP to be inserted into a SUMO cloning vector. The engineered plasmid was then transformed into BL21 Escherichia coli high-expression cells. Cell lysis and the isolation of the supernatant will be performed in order to purify the protein using Fast Protein Liquid Chromatography and a nickel affinity column for the present 6his tag. SDS-PAGE gel will be performed in order to calculate the resulting yield and purity. Beyond these experimentations, I hope to test the peptide’s toxicity towards a panel of bacteria including Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus aureus. Ultimately, the result can lead to the transfer of the AMP to Lactococcus lactis bacterium to allow for testing in the mouse model.
Session Location
- Foster 228
Session Date/Time
- Thursday, 10:00 - 11:00am
Session Type
- Oral Student Presentations
- Student Presentations