Office of Undergraduate Research

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Emphasizing equitable and inclusive access to research opportunities, the University of Maryland's Office of Undergraduate Research (OUR) empowers undergraduates and faculty to engage and succeed in inquiry, creative activity, and scholarship. This collection includes materials shared by undergraduate researchers during OUR events. It also encompasses materials from Undergraduate Research Day 2020, Undergraduate Research Day 2021, and Undergraduate Research Day 2022, which were organized by the Maryland Center for Undergraduate Research.

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    Novel Computational Methods for the Comparison of Leishmania Genomes and Transcriptomes
    (2024-04) Klimes, Daniel; Belew, Trey; El-Sayed, Najib
    Leishmania is a genus of protozoan parasites and the causative agent of Leishmaniasis. Twenty-one infectious species have been identified, with many previously being investigated by DNA and RNA-sequencing. However, significant genetic variation has prevented the comparison of this data across Leishmania species. Gene orthology grouping fails to compare over 70% of Leishmania genes’ expression across multiple species because of this variation. Here, we describe a novel method to reliably compare the genomes and transcriptomes of multiple Leishmania. This method produces a hybrid genome from the genetic sequence of any Leishmania species, while containing the rich sequence annotations of the L. major reference genome. In a demonstrative analysis, our approach allowed the comparison of 87% of genes in L. major against 5 other Leishmania species. Significant genetic variation was found to prevent comparison of many virulence-implicated genes, including surface antigens (e.g. amastins), cysteine proteases, and HSP-83. Within genes that could be compared, parasite transcriptomes segregated primarily by developmental stage (promastigote and amastigote). Transcriptomes secondarily separated by species. Genes upregulated in infection across all Leishmania were identified and included surface amastins, methyltransferases, and an apoptosis inhibition factor. Downregulated genes showed significantly greater sequence conservation than upregulated genes and comprised paraflagellar, flagellar, and HSP-70 proteins among others. The transcriptome differences between the clinical manifestations of leishmaniasis were additionally characterized. Taken together, these results provide much needed insight into the shared Leishmania pathway of infection and survival.
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    Characterizing a Chimera: Comparative Analysis of Pal Endolysin and its Homologs
    (2021-04) Griffin, Ryleigh; Lee, Harrison; O'Hara, Jessica; Nelson, Daniel
    Once a virus infects a cell and produces more virus particles (virions), it must find a way to release those virions so they can infect more cells. Bacteriophage, or viruses that infect bacteria, accomplish this goal by producing endolysins, proteins that cause bacterial cells to lyse by breaking down their cell walls. Many endolysins have a modular structure consisting of an enzymatically active domain (EAD), which catalytically breaks bonds in peptidoglycan, the main component of bacterial cell walls, and a cell wall binding domain (CBD), which attaches the endolysin to the cell wall and determines host specificity. By combining EADs and CBDs from different endolysins, researchers can produce new “chimeric” endolysins in order to kill disease-causing bacteria in a targeted fashion, which can be more effective than the original enzymes. Chimeric endolysins can also form naturally. Bacteriophage Dp-1, which infects Streptococcus pneumoniae bacteria, produces a chimeric endolysin called Pal. Pal’s CBD has the ability to bind to choline and is very similar to a portion of the LytA enzyme produced by S. pneumoniae. Pal’s EAD breaks down amide bonds in peptidoglycan and is very similar to a portion of the endolysin produced by a Bacteriophage BK5-T, which infects Lactococcus lactis bacteria. In our research, we used bioinformatics techniques to find other proteins that share homology with Pal and to investigate the evolutionary relationships between these proteins. We hope that a better understanding of this natural chimeric endolysin could be useful to researchers attempting to engineer new ones.