Biochemistry Commons^™

Therapeutic Potential Of Berberine In Attenuating Cholestatic Liver Injury: Insights From A Psc Mouse Model, Yanyan Wang, Derrick Zhao, Lianyong Su, Yun-Ling Tai, Grayson W. Way, Jing Zeng, Qianhua Yan, Ying Xu, Xuan Wang, Emily C. Gurley, Xi-Qiao Zhou, Jinze Liu, Jinpeng Liu, Weidong Chen, Philip B. Hylemon, Huiping Zhou

Markey Cancer Center Faculty Publications

Background and aims

Primary sclerosing cholangitis (PSC) is a chronic liver disease characterized by progressive biliary inflammation and bile duct injury. Berberine (BBR) is a bioactive isoquinoline alkaloid found in various herbs and has multiple beneficial effects on metabolic and inflammatory diseases, including liver diseases. This study aimed to examine the therapeutic effect of BBR on cholestatic liver injury in a PSC mouse model (Mdr2 −/− mice) and eluci‑ date the underlying mechanisms.

Methods

Mdr2−/− mice (12–14 weeks old, both sexes) received either BBR (50 mg/kg) or control solution daily for eight weeks via oral gavage. Histological and serum biochemical …

A Novel Protozoa Parasite-Derived Protein Adjuvant Is Effective In Immunization With Cancer Cells To Activate The Cancer-Specific Protective Immunity And Inhibit The Cancer Growth In A Murine Model Of Colorectal Cancer, Rajesh Mani, Chloe G. Martin, Kanal E. Balu, Qingding Wang, Piotr G. Rychahou, Tadahide Izumi, B. Mark Evers, Yasuhiro Suzuki

Markey Cancer Center Faculty Publications

Cancer-specific CD8+ cytotoxic T cells play important roles in preventing cancer growth, and IFN-γ, in addition to IL-12 and type I interferon, is critical for activating CD8+ cytotoxic T cells. We recently identified the capability of the amino-terminus region of dense granule protein 6 (GRA6Nt) of Toxoplasma gondii, an intracellular protozoan parasite, to activate IFN-γ production of microglia, a tissue-resident macrophage population. Therefore, in the present study, we examined whether recombinant GRA6Nt protein (rGRA6Nt) functions as an effective adjuvant to potently activate cancer-specific protective immunity using a murine model of MC38 colorectal cancer (CRC). When mice were immunized with non-replicable …

Structure, Dynamics, And Redox Reactivity Of An All-Purpose Flavodoxin, Sharique Khan, Ahmadullah Ansari, Monica Brachi, Debarati Das, Wassim El Housseini, Shelley Minteer, Anne-Francis Miller

Markey Cancer Center Faculty Publications

The flavodoxin of Rhodopseudomonas palustris CGA009 (Rp9Fld) supplies highly reducing equivalents to crucial en- zymes such as hydrogenase, especially when the organism is iron-restricted. By acquiring those electrons from photodriven electron flow via the bifurcating electron transfer flavoprotein, Rp9Fld provides solar power to vital metabolic processes. To understand Rp9Fld’s ability to work with diverse partners, we solved its crystal structure. We observed the canonical fla- vodoxin (Fld) fold and features common to other long-chain Flds but not all the surface loops thought to recognize part- ner proteins. Moreover, some of the loops display alternative structures and dynamics. To advance studies …

Sedimentation Of Large, Soluble Proteins Up To 140 Kda For 1h-Detected Mas Nmr And 13c Dnp Nmr – Practical Aspects, Dallas Bell, Florian Lindemann, Lisa Gerland, Hanna Aucharova, Alexander Klein, Daniel Friedrich, Matthias Hiller, Kristof Grohe, Tobias Meier, Barth Van Rossum, Anne Diehl, Jon Hughes, Leonard J. Mueller, Rasmus Linser, Anne-Frances Miller, Hartmut Oschkinat

Markey Cancer Center Faculty Publications

Solution NMR is typically applied to biological systems with molecular weights < 40 kDa whereas magic-angle-spinning (MAS) solid-state NMR traditionally targets very large, oligomeric proteins and complexes exceeding 500 kDa in mass, including fibrils and crystalline protein preparations. Here, we propose that the gap between these size regimes can be filled by the approach presented that enables investigation of large, soluble and fully protonated proteins in the range of 40–140 kDa. As a key step, ultracentrifugation produces a highly concentrated, gel-like state, resembling a dense phase in spontaneous liquid-liquid phase separation (LLPS). By means of three examples, a Sulfolobus acidocaldarius bifurcat- ing electron transfer flavoprotein (SaETF), tryptophan synthases from Salmonella typhimurium (StTS) and their dimeric β-subunits from Pyrococcus furiosus (PfTrpB), we show that such samples yield well-resolved proton-detected 2D and 3D NMR spectra at 100 kHz MAS without heterogeneous broadening, similar to diluted liquids. Herein, we provide practical guidance on centrifugation conditions and tools, sample behavior, and line widths expected. We demonstrate that the observed chemical shifts correspond to those obtained from μM/low mM solutions or crystalline samples, indicating structural integrity. Nitrogen line widths as low as 20–30 Hz are observed. The presented approach is advantageous for proteins or nucleic acids that cannot be deuterated due to the expression system used, or where relevant protons cannot be re-incorporated after expression in deuterated medium, and it circumvents crystallization. Importantly, it allows the use of low-glycerol buffers in dynamic nuclear polarization (DNP) NMR of proteins as demonstrated with the cyanobacterial phytochrome Cph1.

Non-Transcriptional Irf7 Interacts With Nf-Κb To Inhibit Viral Inflammation, Shumin Fan, Sonam Popli, Sukanya Chakravarty, Ritu Chakravarty, Saurabh Chattopadhyay

Markey Cancer Center Faculty Publications

Interferon (IFN) regulatory factors (IRF) are key transcrip- tion factors in cellular antiviral responses. IRF7, a virus- inducible IRF, expressed primarily in myeloid cells, is required for transcriptional induction of interferon α and antiviral genes. IRF7 is activated by virus-induced phosphory- lation in the cytoplasm, leading to its translocation to the nu- cleus for transcriptional activity. Here, we revealed a nontranscriptional activity of IRF7 contributing to its antiviral functions. IRF7 interacted with the pro-inflammatory tran- scription factor NF-κB-p65 and inhibited the induction of in- flammatory target genes. Using knockdown, knockout, and overexpression strategies, we demonstrated that IRF7 inhibited NF-κB–dependent inflammatory …

Foxs1 Is Increased In Liver Fibrosis And Regulates Tgfβ Responsiveness And Proliferation Pathways In Human Hepatic Stellate Cells, Evelyn A. Bates, Zachary A. Kipp, Wang-Hsin Lee, Genesee J. Martinez, Lauren Weaver, Kathryn N. Becker, Sally Pauss, Justin F. Creeden, Garrett B. Anspach, Robert N. Helsley, Mei Xu, Maria E. C. Bruno, Marlene E. Starr, Terry D. Hinds Jr.

Markey Cancer Center Faculty Publications

Liver fibrosis commences with liver injury stimulating transforming growth factor beta (TGFβ) activation of hepatic stellate cells (HSCs), causing scarring and irreversible damage. TGFβ induces expression of the transcription factor Forkhead box S1 (FOXS1) in hepatocytes and may have a role in the pathogenesis of hepatocellular carcinoma (HCC). To date, no studies have determined how it affects HSCs. We analyzed human livers with cirrhosis, HCC, and a murine fibrosis model and found that FOXS1 expression is significantly higher in fibrotic livers but not in HCC. Next, we treated human LX2 HSC cells with TGFβ to activate fibrotic pathways, and FOXS1 …

Characterization And Evolutionary Analysis Of Poly(Aspartic Acid) Degrading Enzymes: Exploring Enzymes-Dna Interactions And Expanding The Enzyme Family, Thi Ho

College of Graduate Studies: Theses & Dissertations

Poly(aspartic acid) (PAA) has emerged as a biodegradable and environmentally friendly alternative to non- biodegradable polycarboxylates. This thesis aims to further advance the understanding of PAA degradation by exploring multiple facets focusing on PAA-DNA interactions, particularly those involving the enzyme PahZ1 from Pedobacter sp. KP-2, and to investigate their physiological relevance and potential role in the evolution of PAA biodegradation enzymes. Additionally, the research characterizes PahZ1 homologs from various bacterial species, including Brevifollis gellanilyticus, Erythrobacter insulae, Sphingomonadales, and Sphingopyxis sp. Root 1497. These efforts have identified four novel homologs capable of degrading PAA. Synthetic oligopeptides were employed to identify potential …

Mechanistic Analysis Of Four-Way Dna Junctions And Cytokine-Binding Aptamers For Therapeutic Interventions, Roaa S. Mahmoud

Theses and Dissertations

DNA is inherently dynamic and topologically diverse and can fold into many different structures. Besides the canonical Watson-Crick structure, other higher-order structures such as G-quadruplexes (G4), i-motifs (iM), and four-way DNA junctions are possible. Although these high-order DNA structures are known to form transiently, they are important due to the crucial roles they play in many cellular processes including DNA replication, recombination, and repair. Among these DNA structures, 4-way junctions (also known as Holliday junctions, HJ) which are formed during the repair of double-strand DNA breaks (DSBs) and interact with proteins have garnered significant attention due to their central role …

Illuminating Function And Enabling Inhibition At The Protein-Membrane Interface Of Glutathione Peroxidase 4., Courtney L. Labrecque

Theses and Dissertations

Membrane proteins act as gateways to cells and are responsible not only for signaling, lipid transport, and cellular homeostasis, but they are also integral in disease pathologies. One class of membrane proteins, peripheral membrane proteins (PMPs), reside in aqueous compartments of the cell until they are recruited to the membrane to perform their function. Glutathione peroxidase 4 (GPx4) is a PMP enzyme responsible for engaging the membrane and reducing lipid hydroperoxides, thereby preventing cellular death via ferroptosis. Due to its central function surrounding ferroptosis, GPx4 is an interesting drug target that has recently gained interest for inflammatory diseases as well …

Investigating The Roles Of Dapk, P53/Cep-1, And Mitochondrial Damage In Necrotic Neurodegeneration In C. Elegans, Anil Singh

Dissertations and Theses

Stroke is one of the leading causes of death in the U.S., with minority groups, suffering higher fatality rates. Stroke is caused by ischemia, where occlusion of blood supply to the brain results in neurodegeneration. Most of the damage is attributed to excitotoxicity, where an accumulation of the neurotransmitter glutamate in the synapse overstimulates postsynaptic neurons and ultimately leads to cell death (largely by necrosis). Stroke treatments are often ineffective, due to the delay between the onset of stroke and the delivery of effective treatment. To address this, we focus our study on putative later-acting mediators of excitotoxicity such as …

Alopecia As An Early Clinical Marker For Azathioprine Induced Myelosuppression: A Case Report, Nilanjana Dutta , Final Year Mbbs, Dr. M Suresh Babu , Professor, Dr. Subramanian Ramaswamy , Professor, Dr. Mahabaleshwar Mamadapur , Assistant Professor

Digital Journal of Clinical Medicine

Azathioprine is a pro-drug and is metabolized by the TPMT enzyme in the body. In South Asians, Azathioprine is known to cause alopecia and bone marrow suppression in patients with TPMT enzyme deficiency. In India, the prevalence of TPMT mutation varies from 1.2- 10%. A new mutation was detected in 2014, NUDT15 whose incidence varies from 8.5-16%. Patients with mutation in both TPMT and NUDT15 develop myelosuppression faster. In our case, alopecia manifested as the first clinical feature of Azathioprine myelosuppression. Physicians need to recognize early clinical clues (alopecia) to avoid the impending development of myelosuppression and to look for …

Investigations Of A Nox2 Activator, P47phox, Px Domain Membrane Anchoring Interactions And Inhibition, Angela Develin

Theses and Dissertations

The regulation of cellular signaling across plasma membranes is a well-organized process through cross-talk of biomolecules such as proteins and membranes. Peripheral membrane proteins (PMPs) are a class of water soluble, membrane associated, proteins that play a critical role in transducing such signals. Due to the dynamic nature of their membrane interactions, relatively smooth surfaces, and general lack of deep ligand binding pockets, PMPs are commonly associated with an approximate 85% of the human proteome that is classified as ‘undruggable’ by current drug discovery methodologies. One such PMP, p47^phox, contains a PX domain which is essential in activation …

Synthetic Strategies Toward The Development Of Stable Gold-Based Anticancer Agents And Their Mechanistic Insight, Adedamola Arojojoye

Theses and Dissertations--Chemistry

Despite notable advancements in the design and synthesis of novel chemotherapeutic drugs, cancer continues to be a leading cause of death in the United States. Metallodrugs, especially Au complexes, have played a prominent role in the search for the next generation of chemotherapeutic agents. Herein, I report on the synthetic strategies towards the rational design of stable Au (Au)-based agents, study their reactivity in biological environment, and offer insights into the cytotoxic mechanism of action in cancer. Chemotherapeutic Au compounds exist mainly in +I or +III oxidation states. Repurposing of the Au(I) FDA approved auranofin for the treatment of diseases …

Investigating Dynamics Of Electron Transfer Flavoprotein And Its Partner Flavodoxin Via Small Angle Neutron Scattering And Fluorine Nmr, Sharique Ahmad Khan

Theses and Dissertations--Chemistry

Anaerobic bacteria and archaea thrive in seemingly inhospitable environments because they are extremely energy efficient. Their capacity to fully utilize electrochemical energy is based in large part on their ability to conduct electron transfer bifurcation ('bifurcation') at strongly reducing potentials, thereby producing extremely potent reducing agents able to fix nitrogen and make molecular hydrogen. This chemistry is made possible by the use of a flavin as the site of bifurcation, supported by a specialized protein environment and mechanisms that control the flow of individual electrons.

Bifurcating electron transfer flavoproteins (Bf-ETFs) are versatile protein modules that provide the bifurcating capability associated …

Pathology And Diagnosis In Inflammatory-Related Diseases: Covid-19 And Age-Related Macular Degeneration, Zane Russell Lacasse

Graduate Research Theses & Dissertations

Chronic inflammation and dysfunctional inflammatory responses are believed to be contributing factors to the severity of many diseases. Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), it has been recognized that levels of inflammatory markers and the severity of coronavirus disease-2019 (COVID-19) cases are closely related. The work within this dissertation begins with establishing an alternative platform for the diagnosis of COVID-19 and explores ways to enhance the diagnostic utility of this platform. An alternative route for COVID-19 diagnosis was explored using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS). The platform utilizes a non-invasive sampling technique …

Ascertaining A Biochemical Approach To Chlorophyll D Biosynthesis In Acaryochloris Spp., Rashmi Shivni

Graduate Research Theses & Dissertations

Photosynthesis is one of the most abundant metabolic systems on Earth, and specifically, oxygenic photosynthesis primed the planet for complex, multicellular life. The hallmark of modern oxygenic photosynthesis is the photopigment chlorophyll a found in nearly all oxygenic phototrophs as their primary photopigment in their photosynthesis pathways. There are also many organisms that tap into a variety of chlorophylls to extend the energetic limits of photosynthesis, which are largely found as accessory pigments. One genus of cyanobacteria, Acaryochloris, has garnered attention for the ability to undergo photosynthesis by harnessing the far-red part of the visible light spectrum using chlorophyll d …

Shedding Light On Ester Drug Metabolism: Investigating Carboxylesterases In Live Cells With Fluorogenic Chemical Tools, Carolyn J. Karns

Masters Theses

No abstract provided.

Elucidating The Role Of Sialic Acid In Tumorigenic Pathways, Kakali Das

Electronic Theses and Dissertations

Hypersialylation is a prognostic biomarker in cancer cells. The upregulated sialic acid expression on cancer cells facilitates tumorigenesis by playing a critical role in cancer cell proliferation and growth, immune evasion, cell signaling, and metastasis by interacting with various carbohydrate-binding molecules. Sialic acids on cancer cell surface undergo various modifications like O-acetylation at positions 4,7,9 de-acetylation and addition of glycolyl group at position 5. In our first chapter we analyzed the effect of de-acetylated sialic acid on migration via selectin binding in colon cancer cell line HCT116 and in lung cancer cell line A549. Selectins are calcium-dependent cell adhesion molecules …

Neurodevelopmental Vulnerability To Gestational Ozone Exposure, Vishnupriya Alavala, Sarah E. Brent, Christopher G. Canal, Joseph Wang, Russell P. Hunter, Matthew J. Campen, Andrew K. Ottens

UROP Posters

Ambient air pollution accounts for about 4.2 million premature deaths annually per the World Health Organization. Ozone (O3) is a highly reactive air pollutant found in smog and is implicated in cellular damage leading to organ dysfunction. Ambient air pollution is associated with neurodevelopmental, behavioral, and cognitive disorders though ozone’s role is unknown. Studies here look at ozone exposure shortly after implantation vs. shortly before term to evaluate differences in neurodevelopmental susceptibility over time.

To inquire on the effects of ozone on the fetal brain, pregnant Sprague-Dawley rats were exposed once to 0.3 ppm of O3 or filtered air (FA) …

The Study Of Ribosome-Amplified Metabolism, Rambo, Effect In Vitro And In Live Cells, Jianchao Yu

Electronic Theses & Dissertations (2024 - present)

Quinary interactions arise due to the extreme macromolecular crowding inside live cells. Quinary interactions affect intracellular protein stability, activity, and homeostasis. Ribosomes, traditionally known for their role in protein synthesis, have been found to engage in quinary interactions with metabolic enzymes, modulating their activity and thereby revealing a potential regulatory role for ribosomes in cellular metabolism. This phenomenon, termed the Ribosome-Amplified MetaBOlism (RAMBO) effect, was investigated in this dissertation through a series of in vitro and in vivo studies using primarily Nuclear Magnetic Resonance (NMR) spectroscopy.

Firstly, an NMR-based direct enzyme assay compatible with ribosome was developed and validated using …