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Full-Text Articles in Medicinal and Pharmaceutical Chemistry

Structure-Guided Mutagenesis Reveals The Catalytic Residue That Controls The Regiospecificity Of C6-Indole Prenyltransferases, Ahmed R. Aoun, Nagaraju Mupparapu, Diem N. Nguyen, Tae Ho Kim, Christopher M. Nguyen, Zhengfeiyue Pan, Sherif I. Elshahawi May 2023

Structure-Guided Mutagenesis Reveals The Catalytic Residue That Controls The Regiospecificity Of C6-Indole Prenyltransferases, Ahmed R. Aoun, Nagaraju Mupparapu, Diem N. Nguyen, Tae Ho Kim, Christopher M. Nguyen, Zhengfeiyue Pan, Sherif I. Elshahawi

Pharmacy Faculty Articles and Research

Indole is a significant structural moiety and functionalization of the C−H bond in indole-containing molecules expands their chemical space, and modifies their properties and/or activities. Indole prenyltransferases (IPTs) catalyze the direct regiospecific installation of prenyl moieties on indole-derived compounds. IPTs have shown relaxed substrate flexibility enabling them to be used as tools for indole functionalization. However, the mechanism by which certain IPTs target a specific carbon position is not fully understood. Herein, we use structure-guided site-directed mutagenesis, in vitro enzymatic reactions, kinetics and structural-elucidation of analogs to verify the key catalytic residues that control the regiospecificity of all characterized regiospecific …


Cyclic Peptide-Gadolinium Nanocomplexes As Sirna Delivery Tools, Amir Nasrolahi Shirazi, Muhammad Imran Sajid, Dindyal Mandal, David Stickley, Stephanie Nagasawa, Joshua Long, Sandeep Lohan, Keykavous Parang, Rakesh Kumar Tiwari Oct 2021

Cyclic Peptide-Gadolinium Nanocomplexes As Sirna Delivery Tools, Amir Nasrolahi Shirazi, Muhammad Imran Sajid, Dindyal Mandal, David Stickley, Stephanie Nagasawa, Joshua Long, Sandeep Lohan, Keykavous Parang, Rakesh Kumar Tiwari

Pharmacy Faculty Articles and Research

We have recently reported that a cyclic peptide containing five tryptophan, five arginine, and one cysteine amino acids [(WR)5C], was able to produce peptide-capped gadolinium nanoparticles, [(WR)5C]-GdNPs, in the range of 240 to 260 nm upon mixing with an aqueous solution of GdCl3. Herein, we report [(WR)5C]-GdNPs as an efficient siRNA delivery system. The peptide-based gadolinium nanoparticles (50 µM) did not exhibit significant cytotoxicity (~93% cell viability at 50 µM) in human leukemia T lymphoblast cells (CCRF-CEM) and triple-negative breast cancer cells (MDA-MB-231) after 48 h. Fluorescence-activated cell sorting (FACS) analysis indicated …


Label‑Free Spectral Imaging To Study Drug Distribution And Metabolism In Single Living Cells, Qamar Alshammari, Rajasekharreddy Pala, Nir Katzir, Surya M. Nauli Feb 2021

Label‑Free Spectral Imaging To Study Drug Distribution And Metabolism In Single Living Cells, Qamar Alshammari, Rajasekharreddy Pala, Nir Katzir, Surya M. Nauli

Pharmacy Faculty Articles and Research

During drug development, evaluation of drug and its metabolite is an essential process to understand drug activity, stability, toxicity and distribution. Liquid chromatography (LC) coupled with mass spectrometry (MS) has become the standard analytical tool for screening and identifying drug metabolites. Unlike LC/MS approach requiring liquifying the biological samples, we showed that spectral imaging (or spectral microscopy) could provide high-resolution images of doxorubicin (dox) and its metabolite doxorubicinol (dox’ol) in single living cells. Using this new method, we performed measurements without destroying the biological samples. We calculated the rate constant of dox translocating from extracellular moiety into the cell and …


Differential Modulation Of Sk Channel Subtypes By Phosphorylation, Young-Woo Nam, Dezhi Kong, Dong Wang, Razan Orfali, Rinzhin T. Sherpa, Jennifer Totonchy, Surya M. Nauli, Miao Zhang Jan 2021

Differential Modulation Of Sk Channel Subtypes By Phosphorylation, Young-Woo Nam, Dezhi Kong, Dong Wang, Razan Orfali, Rinzhin T. Sherpa, Jennifer Totonchy, Surya M. Nauli, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca2+-activated K+ (SK) channels are voltage-independent and are activated by Ca2+ binding to the calmodulin constitutively associated with the channels. Both the pore-forming subunits and the associated calmodulin are subject to phosphorylation. Here, we investigated the modulation of different SK channel subtypes by phosphorylation, using the cultured endothelial cells as a tool. We report that casein kinase 2 (CK2) negatively modulates the apparent Ca2+ sensitivity of SK1 and IK channel subtypes by more than 5-fold, whereas the apparent Ca2+ sensitivity of the SK3 and SK2 subtypes is only reduced by ∼2-fold, when heterologously …


Astromimetics: The Dawn Of A New Era For (Bio)Materials Science?, Vuk Uskoković, Victoria M. Wu Aug 2018

Astromimetics: The Dawn Of A New Era For (Bio)Materials Science?, Vuk Uskoković, Victoria M. Wu

Pharmacy Faculty Articles and Research

Composite, multifunctional fine particles are likely to be at the frontier of materials science in the foreseeable future. Here we present a submicron composite particle that mimics the stratified structure of the Earth by having a zero-valent iron core, a silicate/silicide mantle, and a thin carbonaceous crust resembling the biosphere and its biotic deposits. Particles were formulated in a stable colloidal form and made to interact with various types of healthy and cancer cells in vitro. A selective anticancer activity was observed, promising from the point of view of the intended use of the particles for tumor targeting across the …


Traceable Peo-Poly(Ester) Micelles For Breast Cancer Targeting: The Effect Of Core Structure And Targeting Peptide On Micellar Tumor Accumulation, Shyam M. Garg, Igor M. Paiva, Mohammad R. Vakili, Rania Soudy, Kate Agopsowicz, Amir H. Soleimani, Mary Hitt, Kamaljit Kaur, Afsaneh Lavasanifar Aug 2017

Traceable Peo-Poly(Ester) Micelles For Breast Cancer Targeting: The Effect Of Core Structure And Targeting Peptide On Micellar Tumor Accumulation, Shyam M. Garg, Igor M. Paiva, Mohammad R. Vakili, Rania Soudy, Kate Agopsowicz, Amir H. Soleimani, Mary Hitt, Kamaljit Kaur, Afsaneh Lavasanifar

Pharmacy Faculty Articles and Research

Traceable poly(ethylene oxide)-poly(ester) micelles were developed through chemical conjugation of a near-infrared (NIR) dye to the poly(ester) end by click chemistry. This strategy was tried for micelles with poly(ε-caprolactone) (PCL) or poly(α-benzyl carboxylate-ε-caprolactone) (PBCL) cores. The surface of both micelles was also modified with the breast cancer targeting peptide, P18-4. The results showed the positive contribution of PBCL over PCL core on micellar thermodynamic and kinetic stability as well as accumulation in primary orthotopic MDA-MB-231 tumors within 4–96 h following intravenous administration in mice. This was in contrast to in vitro studies where better uptake of PEO-PCL versus PEO-PBCL micelles …


Protein Adducts Of Iso[4]Levuglandin E2, A Product Of The Isoprostane Pathway, In Oxidized Low Density Lipoprotein, Robert G. Salomon, Wei Sha, Cynthia Brame, Kamaljit Kaur, Ganesamoorthy Subbanagounder, June O'Neil, Henry F. Hoff, L. Jackson Roberts Ii Jul 1999

Protein Adducts Of Iso[4]Levuglandin E2, A Product Of The Isoprostane Pathway, In Oxidized Low Density Lipoprotein, Robert G. Salomon, Wei Sha, Cynthia Brame, Kamaljit Kaur, Ganesamoorthy Subbanagounder, June O'Neil, Henry F. Hoff, L. Jackson Roberts Ii

Pharmacy Faculty Articles and Research

Levuglandin (LG) E2, a cytotoxic seco prostanoic acid co-generated with prostaglandins by nonenzymatic rearrangements of the cyclooxygenase-derived endoperoxide, prostaglandin H2, avidly binds to proteins. That LGE2-protein adducts can also be generated nonenzymatically is demonstrated by their production during free radical-induced oxidation of low density lipoprotein (LDL). Like oxidized LDL, LGE2-LDL, but not native LDL, undergoes receptor-mediated uptake and impaired processing by macrophage cells. Since radical-induced lipid oxidation produces isomers of prostaglandins, isoprostanes (isoPs), via endoperoxide intermediates, we postulated previously that a similar family of LG isomers, isoLGs, is cogenerated with isoPs. Now …