Life Sciences Commons^™

Characterization Of The Role Of Bgs13 In The Secretory Mechanism Of Pichia Pastoris, Christopher A. Naranjo, Anita Jivan, Maria N. Vo, Katherine De Sa Campos, Jared S. Devarmin, Ryan Hekman, Christina Uribe, Aaron Hang, Kai Her, Michelle M. Fong, Joyce J. Choi, Caroline Chou, Taylor Rabara, Gina Myers, Pachai S. Moua, Der Thor, Douglas D. Risser, Craig Vierra, Andreas Franz, Joan Lin-Cereghino, Geoff Lin-Cereghino

College of the Pacific Faculty Articles

The methylotrophic yeast Pichia pastoris has been utilized for heterologous protein expression for over 30 years. Because P. pastoris secretes few of its own proteins, the exported recombinant protein is the major polypeptide in the extracellular medium, making purification relatively easy. Unfortunately, some recombinant proteins intended for secretion are retained within the cell. A mutant strain isolated in our laboratory, containing a disruption of the BGS13 gene, displayed elevated levels of secretion for a variety of reporter proteins. The Bgs13 peptide (Bgs13p) is similar to the Saccharomyces cerevisiae protein kinase C 1 protein (Pkc1p), but its specific mode of action …

Impact Of High Volume Energy Drink Consumption On Electrocardiographic And Blood Pressure Parameters: A Randomized Trial, Sachin A. Shah, Andy H. Szeto, Raechel Farewell, Allen Shek, Dorothy Fan, Kathy N. Quach, Mouchumi Bhattacharyya, Jasmine Elmiari, Winny Chan, Kate O'Dell, Nancy Nguyen, Tracey J. Mcgaughey, Javed M. Nasir, Sanjay Kaul

School of Pharmacy Faculty Articles

Background Energy drinks have been linked to an increase in emergency room visits and deaths. We aim to determine the impact of energy drinks on electrocardiographic and hemodynamic parameters in young healthy volunteers. Methods and Results A randomized, double-masked, placebo-controlled, crossover study was conducted in healthy volunteers. Participants consumed 32 oz of either energy drink A, energy drink B, or placebo within 60 minutes on 3 study days with a 6-day washout period in between. The primary end point of QT c interval and secondary end points of QT interval, PR interval, QRS duration, heart rate, and brachial and central …

The Arylabialis Muscle Of The Túngara Frog (Engystomops Pustulosus), Amy D. Lagorio, Marcos Gridi-Papp

Pacific Research & Scholarship Day

No abstract provided.

High Efficiency Drug Repurposing Design For New Antifungal Agents, Jong H. Kim, Kathleen L. Chan, Luisa W. Cheng, Lisa A. Tell, Barbara A. Byrne, Kristin Clothier, Kirkwood M. Land

College of the Pacific Faculty Articles

Current antifungal interventions have often limited efficiency in treating fungal pathogens, particularly those resistant to commercial drugs or fungicides. Antifungal drug repurposing is an alternative intervention strategy, whereby new utility of various marketed, non-antifungal drugs could be repositioned as novel antifungal agents. In this study, we investigated "chemosensitization" as a method to improve the efficiency of antifungal drug repurposing, wherein combined application of a second compound (viz., chemosensitizer) with a conventional, non-antifungal drug could greatly enhance the antifungal activity of the co-applied drug. Redox-active natural compounds or structural derivatives, such as thymol (2-isopropyl-5-methylphenol), 4-isopropyl-3-methylphenol, or 3,5-dimethoxybenzaldehyde, could serve as potent …

A Rational Approach For Creating Peptides Mimicking Antibody Binding, Sameer Sachdeva, Hyun Joo, Jerry Tsai, Bhaskara Jasti, Xiaoling Li

School of Pharmacy Faculty Articles

This study reports a novel method to design peptides that mimic antibody binding. Using the Knob-Socket model for protein-protein interaction, the interaction surface between Cetuximab and EGFR was mapped. EGFR binding peptides were designed based on geometry and the probability of the mapped knob-sockets pairs. Designed peptides were synthesized and then characterized for binding specificity, affinity, cytotoxicity of drug-peptide conjugate and inhibition of phosphorylation. In cell culture studies, designed peptides specifically bind and internalize to EGFR overexpressing cells with three to four-fold higher uptake compared to control cells that do not overexpress EGFR. The designed peptide, Pep11, bound to EGFR …

Mechanisms Underlying Neuroprotection By The Nsaid Mefenamic Acid In An Experimental Model Of Stroke, Parto S. Khansari, Robert F. Halliwell

School of Pharmacy Faculty Articles

Stroke is a devastating neurological event with limited treatment opportunities. Recent advances in understanding the underlying pathogenesis of cerebral ischemia support the involvement of multiple biochemical pathways in the development of the ischemic damage. Fenamates are classical non-steroidal anti-inflammatory drugs but they are also highly subunit-selective modulators of GABAA receptors, activators of IKS potassium channels and antagonists of non-selective cation channels and the NLRP3 inflammosome. In the present study we investigated the effect of mefenamic acid (MFA) in a rodent model of ischemic stroke and then addressed the underlying pharmacological mechanisms in vitro for its actions in vivo. The efficacy …

Developmental Expression Of Monocarboxylate Transporter 1 And 4 In Rat Liver, Michael Ng, Justin Louie, Jieyun Cao, Melanie A. Felmlee

School of Pharmacy Faculty Articles

PURPOSE: Monocarboxylate transporters (MCT) are proton-coupled integral membrane proteins that control the influx and efflux of endogenous monocarboxylates such as lactate, acetate and pyruvate. They also transport and mediate the clearance of drugs such as valproate and gamma-hydroxybutyrate. CD147 functions as ancillary protein that chaperones MCT1 and MCT4 to the cell membrane. There is limited data on the maturation of MCT and CD147 expression in tissues related to drug distribution and clearance. The objective of the present study was to quantify hepatic MCT1, MCT4, and CD147 mRNA, whole cell and membrane protein expression from birth to sexual maturity.

METHODS: Liver …

Hiv Viral Rebound Due To A Possible Drug-Drug Interaction Between Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide And Calcium-Containing Products: Report Of 2 Cases, S. Lena Kang-Birken, Dena El-Sayed, John Prichard

School of Pharmacy Faculty Articles

Elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) is a potent fixed-dose, once-daily regimen for HIV-1 treatment and has rare emergence of drug resistance. We report a potential drug-drug interaction in 2 female patients both receiving treatment for HIV and cerebral toxoplasmosis: one case between E/C/F/TAF with calcium carbonate and a second case involving leucovorin as calcium salt. Both cases resulted in rise in HIV RNA levels and emergence of M184 V mutation and resistance to elvitegravir and raltegravir. To the best of our knowledge, these 2 cases are the first reports of rapid emergence of mutation from coadministration of E/C/F/TAF and calcium.

Prebiotics, Probiotics, And Bacterial Infections, Christina C. Tam, Kirkwood M. Land, Luisa W. Cheng

College of the Pacific Faculty Books and Book Chapters

Bacterial pathogens have developed exquisite virulence mechanisms to survive in the host cells. These virulence mechanisms help them bind and internalize into host cells, replicate, and evade the host immune response. The mammalian host itself has developed its own repertoire of weapons to prevent this from happening. One important component of host response in preventing infections in the gut lumen is the diverse commensal microbiota present. Dysbiosis of the gut microbiota has been implicated in the development of many gastrointestinal diseases. A potential therapeutic pathway to solve these diseases would be by providing probiotics and/or prebiotics to help stimulate growth …

Structural Characterization Of Black Widow Spider Dragline Silk Proteins Crp1 And Crp4, Mikayla Shanafelt

University of the Pacific Theses and Dissertations

Spider dragline silk is a biomaterial with outstanding material properties, possessing high-tensile strength and toughness. In nature, dragline silk serves a central role during spider locomotion and web construction. Today, scientists are racing to elucidate the molecular machinery governing silk extrusion, attempting to translate this knowledge into a mimicry process in the laboratory to create synthetic fibers for a wide range of different applications. During extrusion, it has been established that biochemical and mechanical forces govern spidroin folding, aggregation, and assembly. In black widow spiders, at least 7 different proteins have been identified as constituents of dragline silk fibers. These …

Responsible, Safe, And Effective Use Of Biologics In The Management Of Low Back Pain: American Society Of Interventional Pain Physicians (Asipp) Guidelines, Annu Navani, Laxmaiah Manchikanti, Sheri L. Albers, Richard E. Latchaw, Jaya Sanapati, Alan David Kaye, Sairam Atluri, Sheldon Jordan, Ashim Gupta, David Cedeno, Alejandro Vallejo, Bert Fellows, Nebojsa Nick Knezevic, Miguel Pappolla, Sudhir Diwan, Andrea M. Trescot, Amol Soin, Adam M. Kaye, Steve M. Aydin, Aaron K. Calodney, Kenneth D. Candido, Sanjay Bakshi, Ramsin M. Benyamin, Ricardo Vallejo, Art Watanabe, Douglas Beall, Todd P. Stitik, Patrick M. Foye, Erik M. Helander, Joshua A. Hirsch

School of Pharmacy Faculty Articles

BACKGROUND: Regenerative medicine is a medical subspecialty that seeks to recruit and enhance the body's own inherent healing armamentarium in the treatment of patient pathology. This therapy's intention is to assist in the repair, and to potentially replace or restore damaged tissue through the use of autologous or allogenic biologics. This field is rising like a Phoenix from the ashes of underperforming conventional therapy midst the hopes and high expectations of patients and medical personnel alike. But, because this is a relatively new area of medicine that has yet to substantiate its outcomes, care must be taken in its public …

Transcriptome Analysis For Novel Peptide In Breeding Gland Of Hymenochirus Boettgeri, Minjin Ko

University of the Pacific Theses and Dissertations

The primary goal of the project was to find nucleotide sequences potentially encoding a pheromone from the breeding gland of Hymenochirus boettgeri. The reasons in searching for the sequence of a pheromone were to better understand the organism and to use the information for application in reproduction of other species. Due to climate change and rampant deforestation, such as in Africa’s Congo Basin, many amphibian species are being threatened. With these increasing threats, a viable option for the future may be breeding in captivity for the amphibian species. Pheromone characterization from the breeding gland of Hymenochirus boettgeri may help with …

A Trio Of Sigma Factors Control Hormogonium Development In Nostoc Punctiforme, Alfonso Gonzalez Jr.

University of the Pacific Theses and Dissertations

Cyanobacteria are prokaryotes capable of oxygenic photosynthesis, and for many species, nitrogen fixation, giving cyanobacteria an important role in global carbon and nitrogen cycles. Furthermore, multicellular filamentous cyanobacteria are developmentally complex, capable of differentiation into different cell types, including cells capable of nitrogen fixation and cells for motility, making them an ideal platform for studying development, as well as for practical use in biotechnology. Understanding how developmental programmes are activated require an understanding of the role of alternative sigma factors, which are required for transcriptional activation in bacteria. In order to investigate the gene regulatory network and to determine the …

Characterization And Analysis Of Proteins Secreted By The Mutant Pichia Pastoris Strain, Bgs13, Christopher Alan Naranjo

University of the Pacific Theses and Dissertations

The methylotrophic yeast Pichia pastoris has been utilized for heterologous protein expression for research, clinical, and industrial purposes to produce thousands of recombinant protein products. Because P. pastoris secretes very few of its own proteins, the exported recombinant protein is the major polypeptide in the extracellular medium, making purification relatively easy. Unfortunately, a disadvantage to the programmed export is that some recombinant proteins intended for secretion are retained within the cell and may be subsequently degraded. A mutant strain isolated in our lab, containing a pREMI-derived disruption of the BGS13 gene, has displayed elevated levels of secretion for a variety …

Phylogenomic Analyses Clarify Butterfly Species Within The Genus Speyeria Despite Evidence Of A Recent Adaptive Radiation, Erin Thompson

University of the Pacific Theses and Dissertations

The North American genus Speyeria is an especially challenging radiation of butterflies due to ongoing hybridization, incomplete lineage sorting, and similar morphological characters among species. Adaptive radiations often require considerable evidence in order to resolve the evolutionary relationships of closely related individuals. Previous studies of this genus have found paraphyly among species and have been unable to disentangle these taxa due to a lack of data and/or incomplete sampling of the genus. As a result, the interspecific relationships among Speyeria remain unresolved. In an attempt to achieve phylogenetic resolution of the genus, we conducted population genomic and phylogenomic analyses of …

Development Of A Biomarker Panel For Identifying Stressed Marine Mammals, Laura Pujade

University of the Pacific Theses and Dissertations

Increasing anthropogenic disturbance in marine ecosystems such as fishing, oil-drilling, and noise pollution can have detrimental effects on the reproduction and survival of apex predators such as marine mammals. Stress activates the hypothalamic-pituitary-adrenal (HPA) axis, resulting in increased circulating glucocorticoid (GCs) hormones, which alter expression of target genes encoding metabolic enzymes and other mediators of stress. Prolonged HPA axis stimulation may increase catabolism of nutrient stores and suppress immune and reproductive functions, impacting the fitness of marine mammals. GCs measurements are used to identify wild animals experiencing stress. However, these measurements may not be sensitive enough to distinguish between an …

Expression, Purification, And Characterization Of Recombinant Basic Fibroblast Growth Factor In Pichia Pastoris, Henry Hieu Minh Le

University of the Pacific Theses and Dissertations

Wounds in the mouth, occurring after oral surgery, take time to heal. No ointment can be added to help with the healing process because mouth saliva will constantly wash it away. In order to combat this problem, we propose engineering a normal flora microbe to grow at the site of injury and secrete a recombinant growth factor to promote healing of the damaged tissue. Our goal is to have the yeast Pichia pastoris produce human basic fibroblast growth factor (bFGF), which aids in cellular proliferation. P. pastoris is a good choice for this application because not only is it considered …

Knob-Socket Investigation Of Stability And Specificity In Alpha-Helical Secondary And Quaternary Packing Structure, Taylor Renee Rabara

University of the Pacific Theses and Dissertations

The novel knob-socket (KS) model provides a construct to interpret and analyze the direct contributions of amino acid residues to the stability in α-helical protein structures. Based on residue preferences derived from a set of protein structures, the KS construct characterizes intra- and inter-helical packing into regular patterns of simple motifs. The KS model was used in the de novo design of an α-helical homodimer, KSα1.1. Using site-directed mutagenesis, KSα1.1 point mutants were designed to selectively increase and decrease stability by relating KS propensities with changes to α-helical structure. This study suggests that the sockets from the KS Model can …

Investigating The Effect Of Rutaecarpine On The Benzo[A]Pyrene-Induced Dna Damage In Vitro, You Li

University of the Pacific Theses and Dissertations

Benzo[a]pyrene (BaP), is one of the most potent mutagens and carcinogens known. It requires metabolic activation through cytochrome P450 (CYP)1A1 to yield the ultimate carcinogenic metabolite, benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE). BPDE can bind to DNA and form predominantly covalent (+) trans adducts at the N2 position of guanine causing DNA damage. Rutaecarpine (RTC) is an herbal medicine that has been used to treat several diseases such as headache, hypertension, gastrointestinal disorders, amenorrhea, and anti-inflammation. It has also been reported as a potent inducer of CYP enzymes, including CYP1A1, and CYP1A2. The mechanisms underlying up-regulation of CYP1A1 by RTC is dependent on aryl …

Blubber Transcriptome And Proteome Responses To Repeated Adrenocorticotropic Hormone Administration In A Marine Mammal, Jared Deyarmin

University of the Pacific Theses and Dissertations

Chronic physiological stress impacts animal fitness by catabolizing metabolic stores and suppressing reproduction and immunity. This can be especially deleterious for capital breeding carnivores, such as marine mammals, which rely on lipid stores accrued during intensive foraging to sustain prolonged periods of fasting associated with reproduction. Therefore, chronic stress may cause a decrease in fitness in these animals, leading to population declines and potentially detrimental shifts in food web dynamics as a result. However, the impacts and indicators of chronic stress in animals are currently poorly understood. To identify downstream mediators of repeated stress responses in marine mammals, adrenocorticotropic hormone …

Characterization Of The Roles Of Ppp1r15a (Gadd34) And Ppp1r15b (Crep) In Er Stress-Induced Apoptosis In Vivo, Danielle Hicks

University of the Pacific Theses and Dissertations

Failure to balance synthesis, folding and degradation of secreted proteins results in the accumulation of unfolded proteins in the endoplasmic reticulum, termed ER stress. Cells respond to ER stress by activating a signaling pathway known as the unfolded protein response (UPR). The UPR induces phosphorylation of eIF2α to attenuate global protein translation, allowing the ER to clear misfolded proteins. Opposing this function, eIF2α phosphatases contain a catalytic subunit, Protein Phosphatase 1, and either of two homologous scaffolding subunits, GADD34 and CReP. Inhibition of eIF2α phosphatases has been shown to prolong UPR signaling and promote survival in many cells types and …

City Limits: Heat Tolerance Is Influenced By Body Size And Hydration State In An Urban Ant Community, Dustin Jerald Johnson

University of the Pacific Theses and Dissertations

Cities are rapidly expanding, and global warming is intensified in urban environments due to the urban heat island effect. Therefore, urban animals may be particularly susceptible to warming associated with ongoing climate change. Thus, I used a comparative and manipulative approach to test three related hypotheses about the determinants of heat tolerance or critical thermal maximum (CTmax) in urban ants—specifically, that (1) body size, (2) hydration status, and (3) preferred micro-environments influence CTmax. I further tested a fourth hypothesis that native species are particularly physiologically vulnerable in urban environments. I manipulated water access and determined CTmax for 11 species common …

Evaluating Methods Of Obtaining Male Pheromone From Hymenochirus Sp. Using Analytical Chemistry, Vincent Wing-Kun Leung

University of the Pacific Theses and Dissertations

Male Hymenochirus sp. frogs are known to release pheromone that attracts females of the same species. Four methods for collecting secretions containing pheromone in Hymenochirus sp. were tested: norepinephrine injection, gonadotropin-releasing hormone injection, homogenization of gland tissue, and electrostimulation of the skin over the breeding gland area. The samples collected were analyzed using high-performance liquid chromatography (HPLC) and mass spectrometry. The HPLC chromatograph for the male norepinephrine sample contained a peak at 6.4 min that was not in the female norepinephrine sample HPLC chromatograph. The male norepinephrine sample mass spectrum had a peak of m/z 292.0 not in the female …