Little is known about how male and female Pieris rapae behave during territorial behaviors, making this project particularly significant. Through our previous experiment, we have uncovered intriguing insights into the unique behaviors exhibited by male P. rapae when interacting with pseudo-females (males in disguise). Our observations suggest a complex interplay between competitive instincts and courtship behaviors. Specifically, male Pieris rapae display distinct responses when encountering pseudo-females, indicating a potential recognition of the sex of the interacting butterfly. This recognition may trigger competitive behaviors like a territorial move if perceived as a rival male or foster a display of courtship if perceived as a potential mate. Additionally, we aim to study how female P. rapae interact with other females to determine if there are any behavioral differences in these interactions. By studying the intricacies of both male and female courtship and/or territorial behaviors in P. rapae, this project seeks a deeper understanding of the factors shaping mating systems and reproductive success in this species and beyond.

As climate change increases temperature, Pieris rapae caterpillars' feeding habits may be affected. As their feeding habits are altered, P. rapae may begin to migrate to different plants; this can be detrimental for agriculture because these defoliating caterpillars are pests. P. rapae caterpillars are known to feed on Brassica species, including collards and kale. It is also shown that caterpillars increase their feeding rate at higher temperatures (Kingsolver 2000). However, little is known about how temperature influences their feeding preferences. In this experiment, we find the consumption rate of P. rapae 4th instar larvae eating kale (Brassica oleracea var. sabellica) and collards (Brassica oleracea var. viridis) to find consumption preference between these two plants at 14°C, 23°C, and 35°C. Larvae were placed on a moist filter paper in petri dishes containing 2 collard and 2 kale leaf disks placed in an alternating fashion. Petri dishes were placed in three separate incubators set to the three temperatures. We predicted that P. rapae would have a preference for collards since they are reared on collards in the lab and they would increase their consumption of the preferred plant. We also examined the percentage per hour of each leaf eaten and compared this data between types of leaves and temperatures. The data showed that as temperatures increased, the consumption rate of P. rapae caterpillars also increased. Though, there was no change in preference as the P. rapae caterpillars consistently preferred collards over kale. This suggest that higher temperatures from climate change will increase the rate at which caterpillars eat, but will not affect preference. It is important to consider the change in consumption rate of caterpillars with temperature when aiming to prevent crop damage in the face of climate change.

The focus of this research was to test the effectiveness of a silicone-based paint in the marking of Pieris rapae in a manner that was non-invasive and durable. Previous studies have tested other marking methods but have faced challenges such as harm to the organism. By using a paint made from red cabbage (Brassica oleracea), I aim to minimize the harm to larvae in current marking methods while retaining durability under moist conditions. This experiment examined both the durability and health effects of cabbage-based paints on P. rapae caterpillars. Preliminary experiments tested a water-based version, which did not appear to affect survival but faded under moist conditions, and a silicone-based version, which withstood moisture but raised concerns about potential effects on health due to the additional ingredients required for the silicone base. My research continued testing the cabbage paint with a cosmetic-grade dimethicone base and aimed to determine the extent that the cabbage paint may have on caterpillar health and survival. Survival experiments were conducted on 4th and 5th instar caterpillars to determine larva mortality rates when exposed to the pigment. Weight change experiments were conducted from the 4th instar to pupation to be used as a metric of the overall health of the larvae. I conclude that the silicone-based cabbage pigment is a promising marking method for larger caterpillars, offering improved durability and minimal impact on overall health compared to many conventional methods. These findings contribute to the development of safe durable marking techniques suitable for ecological research on soft-bodied insects.

Mycoplasma genitalium (MG) is a common sexually transmitted bacterium that causes serious health problems such as pelvic inflammatory disease, urethritis, and pregnancy complications. The efficacy of antibiotics has significantly decreased due to antibiotic resistance; about 50% of US strains are resistant to azithromycin, a common treatment path, and resistance reaches 100% in high-risk populations. Preliminary research done in our lab has shown that MG is susceptible to tinidazole (another antibiotic) in vitro. We hypothesize that tinidazole is effective against MG because it creates superoxide radicals that MG cannot detoxify. To test this, the sodA and katA genes, encoding enzymes that detoxify reactive oxygen species, were introduced into the MG genome. The insertion site was determined by whole genome sequencing, and we selected two mutants with insertions unlikely to affect other genes. These two strains were compared to the parent strain in time-kill experiments to measure susceptibility to tinidazole. Cultures of these strains were incubated for 10 days with two-fold dilutions of tinidazole, plating aliquots onto agar plates each day to quantify surviving MG. The individual colonies present on the plates are counted and graphed, allowing us to compare the efficacy of tinidazole on the separate strains. To confirm the enzymes are being expressed, we used a hydrogen peroxide assay to measure the levels of hydrogen peroxide, which is formed from the radicals released from the cells. In conclusion, we hypothesize that the radicals produced by tinidazole kill MG by inducing DNA damage. We, therefore, measured the susceptibility of 10 DNA repair mutants to tinidazole and found that deletion of MG_360 enhances susceptibility. Results from these experiments can be used to understand the mechanism by which tinidazole and other nitroimidazoles kill MG. This data is critical in the battle against antibiotic resistance and can improve treatment options globally. 

Mycoplasma genitalium (MG) is a sexually transmitted bacterial pathogen commonly associated with urethritis in men and cervicitis, endometritis, pelvic inflammatory disease, infertility, and preterm birth among women as it invades the upper reproductive tract. Due to antimicrobial resistance, infections can persist for months to years, and first-line drug choices fail in over half of all patients. Whole-genome sequencing reveals that natural nitroimidazole (NDZ)-resistant mutants have mutations in or near MG_342, which encodes a flavin mononucleotide-dependent oxidoreductase required for activation of NDZs to the toxic form. We hypothesize that these mutations reduce oxidoreductase expression or activity, impairing drug efficacy. To determine if these mutations reduce MG342 protein expression, I used molecular techniques to engineer MG strains expressing FLAG-tagged alleles of MG342 including wild type and four spontaneous resistance mutations in or near the MG_342 start codon. FLAG-tags are peptide tags that bind to commercially available, high-affinity antibodies for protein quantification. My study aims to examine how these MG342 mutations affect (1) protein levels using quantitative immunoblots and (2) NDZ susceptibility using qPCR-based minimum inhibitory concentration (MIC) assays. As MG_342 is an essential gene, we hypothesize that an alternate downstream start codon allows sufficient expression for viability of MG while reducing activation of NDZs, leading to resistance. Future RNA sequencing will examine how mutations, particularly a 92 base pair deletion upstream of MG_342, impact transcription. Developing this RNA sequencing method will help define mechanisms of resistance as new mutations are identified. Since physicians are already beginning to treat MG patients with NDZ drugs, insight into the resistance mechanisms could help determine which mutations to screen for to prevent drug-bug mismatch and treatment failure.