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Full-Text Articles in Amino Acids, Peptides, and Proteins

The Pros Of Changing Trna Identity, Michael Ibba Jun 2023

The Pros Of Changing Trna Identity, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The notion that errors in protein synthesis are universally harmful to the cell has been questioned by findings that suggest such mistakes may sometimes be beneficial. However, how often these beneficial mistakes arise from programmed changes in gene expression as opposed to reduced accuracy of the translation machinery is still unclear. A new study published in JBC shows that some bacteria have beneficially evolved the ability to mistranslate specific parts of the genetic code, a trait that allows improved antibiotic resistance.


Hyper Stable Variants Of Fgf-1-Fgf-2 Dimer, Madison Shields Mcclanahan May 2022

Hyper Stable Variants Of Fgf-1-Fgf-2 Dimer, Madison Shields Mcclanahan

Chemistry & Biochemistry Undergraduate Honors Theses

Fibroblast Growth Factors (FGFs), including FGF-1 and FGF-2, are proteins that play a crucial role in cell proliferation, cell differentiation, cell migration, and tissue repair. FGF-1 and FGF-2 are useful in accelerating the healing process in the human body; however, these proteins are naturally thermally unstable, resulting in a relatively low half-life in vivo. 1,8 In efforts to improve the stability of this protein, FGF-1 and FGF-2 proteins are engineered by combining the amino acid sequences of the two proteins to form a heterodimer and obtain novel properties. These two FGF variants are chosen for their specific wound healing capabilities. …


Amphiphilic Cell-Penetrating Peptides Containing Natural And Unnatural Amino Acids As Drug Delivery Agents, David Salehi, Saghar Mozaffari, Khalid Zoghebi, Sandeep Lohan, Dindyal Mandal, Rakesh Tiwari, Keykavous Parang Mar 2022

Amphiphilic Cell-Penetrating Peptides Containing Natural And Unnatural Amino Acids As Drug Delivery Agents, David Salehi, Saghar Mozaffari, Khalid Zoghebi, Sandeep Lohan, Dindyal Mandal, Rakesh Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

A series of cyclic peptides, [(DipR)(WR)4], [(DipR)2(WR)3], [(DipR)3(WR)2], [(DipR)4(WR)], and [DipR]5, and their linear counterparts containing arginine (R) as positively charged residues and tryptophan (W) or diphenylalanine (Dip) as hydrophobic residues, were synthesized and evaluated for their molecular transporter efficiency. The in vitro cytotoxicity of the synthesized peptides was determined in human epithelial ovary adenocarcinoma cells (SK-OV-3), human lymphoblast peripheral blood cells (CCRF-CEM), human embryonic epithelial kidney healthy cells (HEK-293), human epithelial mammary gland adenocarcinoma cells (MDA-MB-468), pig epithelial kidney normal cells (LLC-PK1), and human epithelial …


Escherichia Coli Alanyl-Trna Synthetase Maintains Proofreading Activity And Translational Accuracy Under Oxidative Stress, Arundhati Kavoor, Paul Kelly, Michael Ibba Feb 2022

Escherichia Coli Alanyl-Trna Synthetase Maintains Proofreading Activity And Translational Accuracy Under Oxidative Stress, Arundhati Kavoor, Paul Kelly, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (aaRSs) are enzymes that synthesize aminoacyl-tRNAs to facilitate translation of the genetic code. Quality control by aaRS proofreading and other mechanisms maintains translational accuracy, which promotes cellular viability. Systematic disruption of proofreading, as recently demonstrated for alanyl-tRNA synthetase (AlaRS), leads to dysregulation of the proteome and reduced viability. Recent studies showed that environmental challenges such as exposure to reactive oxygen species can also alter aaRS synthetic and proofreading functions, prompting us to investigate if oxidation might positively or negatively affect AlaRS activity. We found that while oxidation leads to modification of several residues in Escherichia coli AlaRS, unlike …


Keratin 1 As A Cell-Surface Receptor In Cancer, Oluseye Ogunnigbagbe, Christopher G. Bunick, Kamaljit Kaur Dec 2021

Keratin 1 As A Cell-Surface Receptor In Cancer, Oluseye Ogunnigbagbe, Christopher G. Bunick, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Keratins are fibrous proteins that take part in several important cellular functions, including the formation of intermediate filaments. In addition, keratins serve as epithelial cell markers, which has made their role in cancer progression, diagnosis, and treatment an important focus of research. Keratin 1 (K1) is a type II keratin whose structure is comprised of a coiled-coil central domain flanked by flexible, glycine-rich loops in the N- and C-termini. While the structure of cytoplasmic K1 is established, the structure of cell-surface K1 is not known. Several transformed cells, such as cancerous cells and cells that have undergone oxidative stress, display …


Design And Application Of Hybrid Cyclic-Linear Peptide-Doxorubicin Conjugates As A Strategy To Overcome Doxorubicin Resistance And Toxicity, Saghar Mozaffari, David Salehi, Parvin Mahdipoor, Richard Beuttler, Rakesh Tiwari, Hamidreza Montazeri Aliabadi, Keykavous Parang Sep 2021

Design And Application Of Hybrid Cyclic-Linear Peptide-Doxorubicin Conjugates As A Strategy To Overcome Doxorubicin Resistance And Toxicity, Saghar Mozaffari, David Salehi, Parvin Mahdipoor, Richard Beuttler, Rakesh Tiwari, Hamidreza Montazeri Aliabadi, Keykavous Parang

Pharmacy Faculty Articles and Research

Doxorubicin (Dox) is used for breast cancer, leukemia, and lymphoma treatment as an effective chemotherapeutic agent. However, Dox use is restricted due to inherent and acquired resistance and an 8-fold increase in the risk of potentially fatal cardiotoxicity. Hybrid cyclic-linear peptide [R5K]W7A and linear peptide R5KW7A were conjugated with Dox through a glutarate linker to afford [R5K]W7A-Dox and R5KW7A-Dox conjugates to generate Dox derivatives. Alternatively, [R5K]W7C was conjugated with Dox via a disulfide linker to generate [R5K]W7C–S–S-Dox conjugate, where S–S is a disulfide bond. Comparative antiproliferative assays between conjugates [R5K]W7A-Dox, [R5K]W7C–S–S-Dox, linear R5KW7A-Dox, the corresponding physical mixtures of the peptides, …


Suppression Of Dc-Sign And Gh Reveals Complex, Subset-Specific Mechanisms For Kshv Entry In Primary B Lymphocytes, Nancy Palmerin, Farizeh Aalam, Romina Nabiee, Murali Muniraju, Javier Gordon Ogembo, Jennifer Totonchy Jul 2021

Suppression Of Dc-Sign And Gh Reveals Complex, Subset-Specific Mechanisms For Kshv Entry In Primary B Lymphocytes, Nancy Palmerin, Farizeh Aalam, Romina Nabiee, Murali Muniraju, Javier Gordon Ogembo, Jennifer Totonchy

Pharmacy Faculty Articles and Research

Kaposi sarcoma-associated herpesvirus (KSHV) is the causative agent of multiple cancers in immunocompromised patients including two lymphoproliferative disorders associated with KSHV infection of B lymphocytes. Despite many years of research into the pathogenesis of KSHV associated diseases, basic questions related to KSHV molecular virology remain unresolved. One such unresolved question is the cellular receptors and viral glycoproteins needed for KSHV entry into primary B lymphocytes. In this study, we assess the contributions of KSHV glycoprotein H (gH) and the cellular receptor DC-SIGN to KSHV infection in tonsil-derived B lymphocytes. Our results show that (1) neither KSHV-gH nor DC-SIGN are essential …


Dimeric Allostery Mechanism Of The Plant Circadian Clock Photoreceptor Zeitlupe, Francesco Trozzi, Feng Wang, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao Jul 2021

Dimeric Allostery Mechanism Of The Plant Circadian Clock Photoreceptor Zeitlupe, Francesco Trozzi, Feng Wang, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao

Mathematics, Physics, and Computer Science Faculty Articles and Research

In Arabidopsis thaliana, the Light-Oxygen-Voltage (LOV) domain containing protein ZEITLUPE (ZTL) integrates light quality, intensity, and duration into regulation of the circadian clock. Recent structural and biochemical studies of ZTL indicate that the protein diverges from other members of the LOV superfamily in its allosteric mechanism, and that the divergent allosteric mechanism hinges upon conservation of two signaling residues G46 and V48 that alter dynamic motions of a Gln residue implicated in signal transduction in all LOV proteins. Here, we delineate the allosteric mechanism of ZTL via an integrated computational approach that employs atomistic simulations of wild type and …


Comparative Molecular Transporter Properties Of Cyclic Peptides Containing Tryptophan And Arginine Residues Formed Through Disulfide Cyclization, Eman H. M. Mohammed, Dindyal Mandal, Saghar Mozaffari, Magdy Abdel-Hamied Zahran, Amany Mostafa Osman, Rakesh Kumar Tiwari, Keykavous Parang Jun 2020

Comparative Molecular Transporter Properties Of Cyclic Peptides Containing Tryptophan And Arginine Residues Formed Through Disulfide Cyclization, Eman H. M. Mohammed, Dindyal Mandal, Saghar Mozaffari, Magdy Abdel-Hamied Zahran, Amany Mostafa Osman, Rakesh Kumar Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

We have previously reported cyclic cell-penetrating peptides [WR]5 and [WR]4 as molecular transporters. To optimize further the utility of our developed peptides for targeted therapy in cancer cells using the redox condition, we designed a new generation of peptides and evaluated their cytotoxicity as well as uptake behavior against different cancer cell lines. Thus, cyclic [C(WR)xC] and linear counterparts (C(WR)xC), where x = 4–5, were synthesized using Fmoc/tBu solid-phase peptide synthesis, purified, and characterized. The compounds did not show any significant cytotoxicity (at 25 µM) against ovarian (SK-OV-3), leukemia (CCRF-CEM), gastric adenocarcinoma (CRL-1739), breast …


Sensory Primary Cilium Is A Responsive Camp Microdomain In Renal Epithelia, Rinzhin T. Sherpa, Ashraf M. Mohieldin, Rajasekharreddy Pala, Dagmar Wachten, Rennolds S. Ostrom, Surya M. Nauli Apr 2019

Sensory Primary Cilium Is A Responsive Camp Microdomain In Renal Epithelia, Rinzhin T. Sherpa, Ashraf M. Mohieldin, Rajasekharreddy Pala, Dagmar Wachten, Rennolds S. Ostrom, Surya M. Nauli

Pharmacy Faculty Articles and Research

Primary cilia are hair-like cellular extensions that sense microenvironmental signals surrounding cells. The role of adenylyl cyclases in ciliary function has been of interest because the product of adenylyl cyclase activity, cAMP, is relevant to cilia-related diseases. In the present study, we show that vasopressin receptor type-2 (V2R) is localized to cilia in kidney epithelial cells. Pharmacologic inhibition of V2R with tolvaptan increases ciliary length and mechanosensory function. Genetic knockdown of V2R, however, does not have any effect on ciliary length, although the effect of tolvaptan on ciliary length is dampened. Our study reveals that tolvaptan may have a cilia-specific …


Amphiphilic Peptides For Efficient Sirna Delivery, Saghar Mozaffari, Emira Bousoik, Farideh Amirrad, Robert Lamboy, Melissa Coyle, Ryley Hall, Abdulaziz Alasmari, Parvin Mahdipoor, Keykavous Parang, Hamidreza Montazeri Aliabadi Apr 2019

Amphiphilic Peptides For Efficient Sirna Delivery, Saghar Mozaffari, Emira Bousoik, Farideh Amirrad, Robert Lamboy, Melissa Coyle, Ryley Hall, Abdulaziz Alasmari, Parvin Mahdipoor, Keykavous Parang, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

A number of amphiphilic cyclic peptides—[FR]4, [WR]5, and [WK]5—containing hydrophobic and positively-charged amino acids were synthesized by Fmoc/tBu solid-phase peptide methods and evaluated for their efficiency in intracellular delivery of siRNA to triple-negative breast cancer cell lines, MDA-MB-231 and MDA-MB-468, in the presence and absence of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE). Among the peptides, [WR]5, which contains alternate tryptophan (W) and arginine (R) residues, was found to be the most efficient in the delivery of siRNA by improving the delivery by more than 3-fold when compared to other synthesized cyclic peptides that were not efficient. The data also showed that co-formulation of [WR]5 …


Characterization Of Theranostic Peptides For Glioblastoma Multiforme, Aaron Mellesmoen Aug 2018

Characterization Of Theranostic Peptides For Glioblastoma Multiforme, Aaron Mellesmoen

All NMU Master's Theses

Glioblastoma multiforme (GBM) is a type of primary CNS tumor in which viable treatment options do not exist. Standard of care including tumor resection, chemotherapy, and radiation does little to extend the 5-year survival expectancy past 5.1%. Herein, two small-peptide molecules with inherent antitumor activity, blood-brain barrier permeability, and capability for tumor-specific drug deliverance and intraoperative visualization (termed theranostic) were of focus. Confocal microscopy was employed to characterize in vitro specificity of chlorotoxin, a 4 kDa scorpion venom peptide, and rBSG, the recombinant 25 kDa non-glycosylated extracellular domain of extracellular matrix metalloproteinase inducer (EMMPRIN; Basigin) isoform …


Efficient Intracellular Delivery Of Cell-Impermeable Cargo Molecules By Peptides Containing Tryptophan And Histidine, Amir Nasrolahi Shirazi, Saghar Mozaffari, Rinzhin Tshering Sherpa, Rakesh Tiwari, Keykavous Parang Jun 2018

Efficient Intracellular Delivery Of Cell-Impermeable Cargo Molecules By Peptides Containing Tryptophan And Histidine, Amir Nasrolahi Shirazi, Saghar Mozaffari, Rinzhin Tshering Sherpa, Rakesh Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

We have previously evaluated and reported numerous classes of linear and cyclic peptides containing hydrophobic and hydrophilic segments for intracellular delivery of multiple molecular cargos. Herein, a combination of histidine and tryptophan amino acids were designed and evaluated for their efficiency in intracellular delivery of cell-impermeable phosphopeptides and the anti-HIV drug, emtricitabine. Two new decapeptides, with linear and cyclic natures, both containing alternate tryptophan and histidine residues, were synthesized using Fmoc/tBu solid-phase chemistry. The peptides were characterized and purified by using matrix-assisted laser desorption/ionization (MALDI) spectroscopy and high-performance liquid chromatography (HPLC), respectively. These peptides did not show significant toxicity up …


Identification Of Potential Drug Targets In Cancer Signaling Pathways Using Stochastic Logical Models, Peican Zhu, Hamidreza Montazeri Aliabadi, Hasan Uludag, Jie Han Mar 2016

Identification Of Potential Drug Targets In Cancer Signaling Pathways Using Stochastic Logical Models, Peican Zhu, Hamidreza Montazeri Aliabadi, Hasan Uludag, Jie Han

Pharmacy Faculty Articles and Research

The investigation of vulnerable components in a signaling pathway can contribute to development of drug therapy addressing aberrations in that pathway. Here, an original signaling pathway is derived from the published literature on breast cancer models. New stochastic logical models are then developed to analyze the vulnerability of the components in multiple signalling sub-pathways involved in this signaling cascade. The computational results are consistent with the experimental results, where the selected proteins were silenced using specific siRNAs and the viability of the cells were analyzed 72 hours after silencing. The genes elF4E and NFkB are found to have nearly no …


Peptide Arrays For Detecting Naphthenic Acids In Oil Sands Process Affected Water, Kamaljit Kaur, Subir Bhattacharjee, Rajesh G. Pillai, Sahar Ahmed, Sarfuddin Azmi Nov 2014

Peptide Arrays For Detecting Naphthenic Acids In Oil Sands Process Affected Water, Kamaljit Kaur, Subir Bhattacharjee, Rajesh G. Pillai, Sahar Ahmed, Sarfuddin Azmi

Pharmacy Faculty Articles and Research

Naphthenic acids (NAs) are water-soluble components of petroleum. The characterization and quantification of NAs by analytical methods have proved quite challenging, whilst the toxic effects of these water-soluble compounds on a variety of organisms adversely affecting reproduction and steroid production is becoming apparent. In this study, we report a fluorescence-based competitive binding method for rapid sensing of the presence of NAs using cellulosic peptide array strips as sensors. The peptide array was designed from sequences derived from the estrogen receptor (ER). Several of these peptides were able to detect the presence of NAs at low micromolar (∼5 mg L−1 …