Julissa Burgos, '20


Julissa Burgos, '20





Julissa Burgos was born and raised in Bayamón, Puerto Rico. She is pursuing a bachelor’s degree in Biomedical Sciences and a minor in Chemistry. Julissa is currently isolating and characterizing a heme protein involved in N-nitroglycine biosynthesis under the guidance of Dr. Jonathan D. Caranto. She plans to obtain her Ph.D. In Microbiology and become a research scientist. She hopes to collaborate with other scientists to aid in controlling outbreaks caused by pathogens.

Faculty Mentor

Salvador Almagro-Moreno, Ph.D.

Undergraduate Major

Biomedical Sciences with Chemistry minor

Future Plans

Ph.D. in Microbiology


Title: Applying Surface Enhanced Raman Spectroscopy for bacterial detection in water.

Institution: Conducted at the Chemistry Department of the University of Puerto Rico, Mayagüez campus

Mentor: Dr. Marco de Jesús, Ph.D. Chemistry Department, University of Puerto Rico, Mayagüez campus

Outbreaks of bacteria in food and water have caused concerns in water treatment facilities, pharmaceutical companies, and food processing facilities. The issues that can be caused by pathogenic bacteria calls for new methods that can rapidly and effectively detect them in order to avoid economic losses, deaths, and illness. Surface Enhanced Raman Spectroscopy is an emerging technique for the detection of bacteria since it is less time consuming, cost effective, and it can distinguish between live and dead bacteria. This work employs cellulose filters as a substrate material for SERS detection. The filter is coated with silver nanoparticles because they enhance the bacterial signals. Different amounts of pathogenic bacteria are filtered through the membrane to see which is the minimum CFU of bacteria detected. Preliminary results show that SERS can detect pathogenic bacteria with Ag cellulose membrane and test the limit amount of detection for the substrate. The characteristic E.coli bands at 730cm-1 and 1318 cm-1 will be monitored and discussed.

Title:The Study of N-Terminal Methylation of hOLA1 catalyzed by NRMT1 and its potential role in cancer

Institution: Conducted at Kansas State University part of the Research Experience for Undergraduates (REU) program

Mentor: Dr. Ping Li, Ph.D. Department of Chemistry, Kansas State University

Multiple studies have proven that the protein Obg-like ATPase 1, referred to as OLA1, is associated with different types of cancers. This protein has important functions in cellular processes and plays a significant role in the migration and invasion of breast cancer cells. hOLA1 is predicted to be a targeted substrate for α N-terminal RCC1 methyltransferase (NRMT1) because it shares the N-terminal Met-Pro-Pro-Lys motif sequence. NRMT1 can catalyze the N-terminal methylation by the addition of S-adenosyl-L-methionine (SAM), a methyl donor. This project aims to study whether hOLA1 can be N-terminally methylated by NRMT1 as well as its roles in carcinogenesis. The preliminary studies focus on the in vitro methylation at a peptide level because it is more cost effective and easier to characterize. The N-terminally methylated peptide was characterized by using the techniques of Mass Spectrometry and HPLC. These results indicate that the protein hOLA1 can be methylated by NRMT1 in vivo.

Title: Fishing for New Regulators of the Enterotoxin Gene Cluster in Staphylococcus aureus.

Institution: Staphylococcus aureus is an opportunistic bacterial pathogen known to cause around 600,000 cases of infectious diseases annually. It is the leading cause of infective endocarditis (IE), which is a bacterial infection caused by the formation of vegetation on the heart valves and tissue with a mortality rate of 30% to 60% if left untreated. Superantigens (SAgs), virulence factors produced by S. aureus strains, are critical for endocarditis development. A specific group of SAgs, the enterotoxin gene cluster (egc), contributes to the development of IE but the mechanism by which it mediates its effects is poorly understood. We aim to study the regulatory mechanisms controlling the egc expression. However, because of it low in vitro expression, our approach will rely on the overexpression of global regulators. The strain S.aureus MN8, a well-characterized strain that encodes the egc will be used for this purpose. A two-plasmid vector system was constructed containing one plasmid with a green fluorescent protein (GFP) under the control of the egc promoter and the second plasmid consisting of a global regulator under control of a xylose-inducible promoter. Protein detection with overexpression of regulators will be analyzed through western blots and gene activation will be measured by detection of GFP fluorescent reporters and qPCR. Preliminary data with Agr and MgrA, global regulators that were tested in the two-plasmid vector system indicated no overexpression of the egc. For this reason, we want to overexpress other global regulators and have insight into the role of the egc in the development of staphylococcal IE.


Chemistry | Medicine and Health Sciences

Julissa Burgos, '20