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Full-Text Articles in Chemicals and Drugs

Cyclic Peptides Containing Tryptophan And Arginine As Src Kinase Inhibitors, Amir Nasrolahi Shirazi, Rakesh Tiwari, Alex Brown, Dindyal Mandal, Gongqin Sun, Keykavous Parang Jun 2013

Cyclic Peptides Containing Tryptophan And Arginine As Src Kinase Inhibitors, Amir Nasrolahi Shirazi, Rakesh Tiwari, Alex Brown, Dindyal Mandal, Gongqin Sun, Keykavous Parang

Pharmacy Faculty Articles and Research

A number of cyclic and linear peptides containing various combinations of amino acids were evaluated for their Src kinase inhibitory potency. Among all the peptides, cyclic decapeptide C[RW]5 containing alternative arginine (R) and tryptophan (W) residues was found to be the most potent Src kinase inhibitor. C[RW]5 showed higher inhibitory activity (IC50=2.8 μM) than C[KW]5, L(KW)5, C[RW]4, and C[RW]3 with IC50 values of 46.9, 69.1, 21.5, and 25.0 μM, respectively, as determined in a fluorescence intensity-based assay. Thus, the cyclic nature, the presence of arginine, ring size, and the number of amino acids in the structure of the peptide were …


Label-Free Detection Of Low Protein Concentration In Solution Using A Novel Colorimetric Assay, Molla R. Islam, Michael J. Serpe May 2013

Label-Free Detection Of Low Protein Concentration In Solution Using A Novel Colorimetric Assay, Molla R. Islam, Michael J. Serpe

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Dual pH and temperature sensitive microgel-based etalons were fabricated by sandwiching a “monolithic” microgel layer between two semitransparent, Au layers. The devices exhibit visual color and multipeak reflectance spectra, both of which primarily depend on the distance between the Au surfaces mediated by the microgel diameter. We found that a polycationic polyelectrolyte can penetrate through the Au overlayer to interact with negatively charged microgel confined between Au overlayers. In this submission we report that biotinylated polycationic polymer can penetrate through the Au overlayer of a poly (N-isopropylacrylamide)-co-acrylic acid (pNIPAm-co-AAc) microgel-based etalon and cause the microgel layer to collapse. The collapse …


Divergent Protein Motifs Direct Ef-P Mediated Translational Regulation In Salmonella And Escherichia Coli, Steven J. Hersch, Mengchi Wang, S. Betty Zou, Kyung-Mee Moon, Leonard J. Foster, Michael Ibba, William Wiley Navarre Apr 2013

Divergent Protein Motifs Direct Ef-P Mediated Translational Regulation In Salmonella And Escherichia Coli, Steven J. Hersch, Mengchi Wang, S. Betty Zou, Kyung-Mee Moon, Leonard J. Foster, Michael Ibba, William Wiley Navarre

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is a universally conserved bacterial translation factor homologous to eukaryotic/archaeal initiation factor 5A. In Salmonella, deletion of the efp gene results in pleiotropic phenotypes, including increased susceptibility to numerous cellular stressors. Only a limited number of proteins are affected by the loss of EF-P, and it has recently been determined that EF-P plays a critical role in rescuing ribosomes stalled at PPP and PPG peptide sequences. Here we present an unbiased in vivo investigation of the specific targets of EF-P by employing stable isotope labeling of amino acids in cell culture (SILAC) to compare the …


Design, Synthesis And Evaluation Of Antimicrobial Activity Of N-Terminal Modified Leucocin A Analogues, Krishna Chaitanya Bodapati, Rania Soudy, Hashem Etayash, Michael Stiles, Kamaljit Kaur Apr 2013

Design, Synthesis And Evaluation Of Antimicrobial Activity Of N-Terminal Modified Leucocin A Analogues, Krishna Chaitanya Bodapati, Rania Soudy, Hashem Etayash, Michael Stiles, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Class IIa bacteriocins are potent antimicrobial peptides produced by lactic acid bacteria to destroy competing microorganisms. The N-terminal domain of these peptides consists of a conserved YGNGV sequence and a disulphide bond. The YGNGV motif is essential for activity, whereas, the two cysteines involved in the disulphide bond can be replaced with hydrophobic residues. The C-terminal region has variable sequences, and folds into a conserved amphipathic α-helical structure. To elucidate the structure–activity relationship in the N-terminal domain of these peptides, three analogues (1–3) of a class IIa bacteriocin, Leucocin A (LeuA), were designed and synthesized by …


Revisiting The Fundamentals In The Design And Control Of Nanoparticulate Colloids In The Frame Of Soft Chemistry, Vuk Uskoković Jan 2013

Revisiting The Fundamentals In The Design And Control Of Nanoparticulate Colloids In The Frame Of Soft Chemistry, Vuk Uskoković

Pharmacy Faculty Articles and Research

This review presents thoughts on some of the fundamental features of conceptual models applied in the design of fine particles in the frames of colloid and soft chemistry. A special emphasis is placed on the limitations of these models, an acknowledgment of which is vital in improving their intricacy and effectiveness in predicting the outcomes of the corresponding experimental settings. Thermodynamics of self-assembly phenomena illustrated on the examples of protein assembly and micellization is analyzed in relation to the previously elaborated thesis that each self-assembly in reality presents a co-assembly, since it implies a mutual reorganization of the assembling system …


Copper Triflate-Mediated Synthesis Of 1,3,5-Triarylpyrazoles In [Bmim][Pf6] Ionic Liquid And Evaluation Of Their Anticancer Activities, V. Kameshwara Rao, Rakesh Tiwari, Bhupender S. Chhikara, Amir Nasrolahi Shirazi, Keykavous Parang, Anil Kumar Jan 2013

Copper Triflate-Mediated Synthesis Of 1,3,5-Triarylpyrazoles In [Bmim][Pf6] Ionic Liquid And Evaluation Of Their Anticancer Activities, V. Kameshwara Rao, Rakesh Tiwari, Bhupender S. Chhikara, Amir Nasrolahi Shirazi, Keykavous Parang, Anil Kumar

Pharmacy Faculty Articles and Research

A simple, efficient, and environment friendly protocol for the synthesis of 1,3,5-triarylpyrazoles and 1,3,5-triarylpyrazolines in [bmim][PF6] ionic liquid mediated by Cu(OTf)2 is described. The reaction protocol gave 1,3,5-triarylpyrazoles in good to high yields (71–84%) via a one-pot addition–cyclocondensation between chalcones and arylhydrazines, and oxidative aromatization without the requirement for an additional oxidizing reagent. The catalyst can be reused for up to four cycles without much loss in the catalytic activity. The pyrazoles (4a–o) and pyrazolines (3a–n) were evaluated for their antiproliferative activity in SK-OV-3, HT-29, and HeLa human cancer cells lines. Among all the compounds, 3b inhibited cell proliferation of …


Synthesis Of Pyrazolo[3,4-D]Pyrimidine Derivatives And Evaluation Of Their Src Kinase Inhibitory Activities, Anil Kumar, Guofeng Ye, Xianfeng Gu, Yuehao Wang, Gongqin Sun, Keykavous Parang Jan 2013

Synthesis Of Pyrazolo[3,4-D]Pyrimidine Derivatives And Evaluation Of Their Src Kinase Inhibitory Activities, Anil Kumar, Guofeng Ye, Xianfeng Gu, Yuehao Wang, Gongqin Sun, Keykavous Parang

Pharmacy Faculty Articles and Research

A series of pyrazolo[3,4-d]pyrimidine derivatives was synthesized and evaluated for the Src kinase inhibitory activities. Compound 6e and 10c exhibited inhibition of Src kinase with an IC50 value of 5.6 and 5.1 μM, respectively. Hydroxamate derivative 15a was found to be a metal-mediated inhibitor for human Csk with an IC50 value of 2.0 μM showing 56-fold selectivity over Src kinase inhibition.


Chikungunya Virus Infection Results In Higher And Persistent Viral Replication In Aged Rhesus Macaques Due To Defects In Anti-Viral Immunity, Ilhem Messaoudi, Jennifer Totonchy, Thomas Totonchy, Craig N. Kreklywich, Kristen Haberthur, Laura Springgay, James D. Brien, Michael S. Diamond, Victor R. Defilippis, Daniel N. Streblow Jan 2013

Chikungunya Virus Infection Results In Higher And Persistent Viral Replication In Aged Rhesus Macaques Due To Defects In Anti-Viral Immunity, Ilhem Messaoudi, Jennifer Totonchy, Thomas Totonchy, Craig N. Kreklywich, Kristen Haberthur, Laura Springgay, James D. Brien, Michael S. Diamond, Victor R. Defilippis, Daniel N. Streblow

Pharmacy Faculty Articles and Research

Chikungunya virus (CHIKV) is a re-emerging mosquito-borne Alphavirus that causes a clinical disease involving fever, myalgia, nausea and rash. The distinguishing feature of CHIKV infection is the severe debilitating poly-arthralgia that may persist for several months after viral clearance. Since its re-emergence in 2004, CHIKV has spread from the Indian Ocean region to new locations including metropolitan Europe, Japan, and even the United States. The risk of importing CHIKV to new areas of the world is increasing due to high levels of viremia in infected individuals as well as the recent adaptation of the virus to the mosquito species Aedes …


Aberrant Proliferation In Cxcr7+ Endothelial Cells Via Degradation Of The Retinoblastoma Protein, Jennifer Totonchy, Jessica M. Osborn, Sara Botto, Lisa Clepper, Ashlee V. Moses Jan 2013

Aberrant Proliferation In Cxcr7+ Endothelial Cells Via Degradation Of The Retinoblastoma Protein, Jennifer Totonchy, Jessica M. Osborn, Sara Botto, Lisa Clepper, Ashlee V. Moses

Pharmacy Faculty Articles and Research

Angiogenesis is a critical factor in the growth and dissemination of solid tumors. Indeed, tumor vasculature is abnormal and contributes to the development and spread of malignancies by creating a hostile microenvironment. The alternative SDF-1/CXCL12 receptor, CXCR7, is frequently and specifically expressed in tumor-associated vessels. In this study, we examine the role of endothelium-expressed CXCR7 in tumor vascular dysfunction by specifically examining the contribution of CXCR7 to endothelial cell (EC) proliferation. We demonstrate that CXCR7 expression is sufficient to drive post-confluent growth in EC cultures. Further, we provide a novel mechanism for CXCR7-mediated proliferation via proteasomal degradation of the tumor …


Self-Assembled Surfactant Cyclic Peptide Nanostructures As Stabilizing Agents, Dindyal Mandal, Rakesh Tiwari, Amir Nasrolahi Shirazi, Donghoon Oh, Guofeng Ye, Antara Banerjee, Arpita Yadav, Keykavous Parang Jan 2013

Self-Assembled Surfactant Cyclic Peptide Nanostructures As Stabilizing Agents, Dindyal Mandal, Rakesh Tiwari, Amir Nasrolahi Shirazi, Donghoon Oh, Guofeng Ye, Antara Banerjee, Arpita Yadav, Keykavous Parang

Pharmacy Faculty Articles and Research

A number of cyclic peptides including [FR](4), [FK](4), [WK](5), [CR](4), [AK](4), and [WR](n) (n = 3-5) containing L-amino acids were produced using solid-phase peptide synthesis. We hypothesized that an optimal balance of hydrophobicity and charge could generate self-assembled nanostructures in aqueous solution by intramolecular and/or intermolecular interactions. Among all the designed peptides, [WR](n) (n = 3-5) generated self-assembled vesicle-like nanostructures at room temperature as shown by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and/or dynamic light scattering (DLS). This class of peptides represents the first report of surfactant-like cyclic peptides that self-assemble into nanostructures. A plausible mechanistic insight into …


Differential Modulation Of Functional Dynamics And Allosteric Interactions In The Hsp90-Cochaperone Complexes With P23 And Aha1: A Computational Study, Kristin Blacklock, Gennady M. Verkhivker Jan 2013

Differential Modulation Of Functional Dynamics And Allosteric Interactions In The Hsp90-Cochaperone Complexes With P23 And Aha1: A Computational Study, Kristin Blacklock, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Allosteric interactions of the molecular chaperone Hsp90 with a large cohort of cochaperones and client proteins allow for molecular communication and event coupling in signal transduction networks. The integration of cochaperones into the Hsp90 system is driven by the regulatory mechanisms that modulate the progression of the ATPase cycle and control the recruitment of the Hsp90 clientele. In this work, we report the results of computational modeling of allosteric regulation in the Hsp90 complexes with the cochaperones p23 and Aha1. By integrating protein docking, biophysical simulations, modeling of allosteric communications, protein structure network analysis and the energy landscape theory we …


(R)-Β-Lysine Modified Elongation Factor P Functions In Translation Elongation, Tammy J. Bullwinkle, S. Betty Zou, Andrei Rajkovic, Steven J. Hersch, Sara Elgamal, Nathaniel Robinson, David Smil, Yuri Bolshan, William Wiley Navarre, Michael Ibba Dec 2012

(R)-Β-Lysine Modified Elongation Factor P Functions In Translation Elongation, Tammy J. Bullwinkle, S. Betty Zou, Andrei Rajkovic, Steven J. Hersch, Sara Elgamal, Nathaniel Robinson, David Smil, Yuri Bolshan, William Wiley Navarre, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Post-translational modification of bacterial elongation factor P (EF-P) with (R)-β-lysine at a conserved lysine residue activates the protein in vivo and increases puromycin reactivity of the ribosome in vitro. The additional hydroxylation of EF-P at the same lysine residue by the YfcM protein has also recently been described. The roles of modified and unmodified EF-P during different steps in translation, and how this correlates to its physiological role in the cell, have recently been linked to the synthesis of polyproline stretches in proteins. Polysome analysis indicated that EF-P functions in translation elongation, rather than initiation as proposed previously. This was …


Selection Of Trna Charging Quality Control Mechanisms That Increase Mistranslation Of The Genetic Code, Srujana S. Yadavalli, Michael Ibba Dec 2012

Selection Of Trna Charging Quality Control Mechanisms That Increase Mistranslation Of The Genetic Code, Srujana S. Yadavalli, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Mistranslation can follow two events during protein synthesis: production of non-cognate amino acid:transfer RNA (tRNA) pairs by aminoacyl-tRNA synthetases (aaRSs) and inaccurate selection of aminoacyl-tRNAs by the ribosome. Many aaRSs actively edit non-cognate amino acids, but editing mechanisms are not evolutionarily conserved, and their physiological significance remains unclear. To address the connection between aaRSs and mistranslation, the evolutionary divergence of tyrosine editing by phenylalanyl-tRNA synthetase (PheRS) was used as a model. Certain PheRSs are naturally error prone, most notably a Mycoplasma example that displayed a low level of specificity consistent with elevated mistranslation of the proteome. Mycoplasma PheRS was found …


Pharmacokinetics And Brain Uptake In The Rhesus Monkey Of A Fusion Protein Of Arylsulfatase A And A Monoclonal Antibody Against The Human Insulin Receptor, Ruben J. Boado, Jeff Zhiqiang Lu, Eric Ka-Wai Hui, Rachita K. Sumbria, William M. Pardridge Nov 2012

Pharmacokinetics And Brain Uptake In The Rhesus Monkey Of A Fusion Protein Of Arylsulfatase A And A Monoclonal Antibody Against The Human Insulin Receptor, Ruben J. Boado, Jeff Zhiqiang Lu, Eric Ka-Wai Hui, Rachita K. Sumbria, William M. Pardridge

Pharmacy Faculty Articles and Research

Metachromatic leukodystrophy (MLD) is a lysosomal storage disorder of the brain caused by mutations in the gene encoding the lysosomal sulfatase, arylsulfatase A (ASA). It is not possible to treat the brain in MLD with recombinant ASA, because the enzyme does not cross the blood-brain barrier (BBB). In the present investigation, a BBB-penetrating IgG-ASA fusion protein is engineered and expressed, where the ASA monomer is fused to the carboxyl terminus of each heavy chain of an engineered monoclonal antibody (MAb) against the human insulin receptor (HIR). The HIRMAb crosses the BBB via receptor-mediated transport on the endogenous BBB insulin receptor, …


Development Of A Men’S Preference For Testosterone Replacement Therapy (P-Trt) Instrument, Sheryl L. Szeinbach, Enrique Seoane-Vazquez, Kent H. Summers Aug 2012

Development Of A Men’S Preference For Testosterone Replacement Therapy (P-Trt) Instrument, Sheryl L. Szeinbach, Enrique Seoane-Vazquez, Kent H. Summers

Pharmacy Faculty Articles and Research

Background: This study used a standard research approach to create a final conceptual model and the Preference for the Testosterone Replacement Therapy (P-TRT) instrument.

Methods: A discussion guide was developed from a literature review and expert opinion to direct one-on-one interviews with participants who used testosterone replacement therapy and consented to participate in the study. Data from telephone interviews were transcribed for theme analysis using NVivo 9 qualitative analysis software, analyzed descriptively from a saturation grid, and used to evaluate men’s P-TRT. Data from cognitive debriefing for five participants were used to evaluate the final conceptual model and …


Identification Of The Functional Binding Pocket For Compounds Targeting Small-Conductance Ca2+-Activated Potassium Channels, Miao Zhang, John M. Pascal, Marcel Schumann, Roger S. Armen, Ji-Fang Zhang Aug 2012

Identification Of The Functional Binding Pocket For Compounds Targeting Small-Conductance Ca2+-Activated Potassium Channels, Miao Zhang, John M. Pascal, Marcel Schumann, Roger S. Armen, Ji-Fang Zhang

Pharmacy Faculty Articles and Research

Small- and intermediate-conductance Ca2+-activated potassium channels, activated by Ca2+-bound calmodulin, play an important role in regulating membrane excitability. These channels are also linked to clinical abnormalities. A tremendous amount of effort has been devoted to developing small molecule compounds targeting these channels. However, these compounds often suffer from low potency and lack of selectivity, hindering their potentials for clinical use. A key contributing factor is the lack of knowledge of the binding site(s) for these compounds. Here we demonstrate by X-ray crystallography that the binding pocket for the compounds of the 1-EBIO class is located at the calmodulin-channel interface. We …


Taking Aim At The Start Of Translation, Medha Raina, Michael Ibba Aug 2012

Taking Aim At The Start Of Translation, Medha Raina, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

No abstract provided.


A Pseudo-Trna Modulates Antibiotic Resistance In Bacillus Cereus, Theresa E. Rogers, Sandro F. Ataide, Kiley Dare, Assaf Katz, Stephanie Seveau, Hervé Roy, Michael Ibba Jul 2012

A Pseudo-Trna Modulates Antibiotic Resistance In Bacillus Cereus, Theresa E. Rogers, Sandro F. Ataide, Kiley Dare, Assaf Katz, Stephanie Seveau, Hervé Roy, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bacterial genomic islands are often flanked by tRNA genes, which act as sites for the integration of foreign DNA into the host chromosome. For example, Bacillus cereus ATCC14579 contains a pathogenicity island flanked by a predicted pseudo-tRNA, tRNAOther, which does not function in translation. Deletion of tRNAOther led to significant changes in cell wall morphology and antibiotic resistance and was accompanied by changes in the expression of numerous genes involved in oxidative stress responses, several of which contain significant complementarities to sequences surrounding tRNAOther. This suggested that tRNAOther might be expressed as part of a larger RNA, and RACE analysis …


Association Of A Multi-Synthetase Complex With Translating Ribosomes In The Archaeon Thermococcus Kodakarensis, Medha Raina, Sara Elgamal, Thomas J. Santangelo, Michael Ibba Jun 2012

Association Of A Multi-Synthetase Complex With Translating Ribosomes In The Archaeon Thermococcus Kodakarensis, Medha Raina, Sara Elgamal, Thomas J. Santangelo, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

In archaea and eukaryotes aminoacyl-tRNA synthetases (aaRSs) associate in multi-synthetase complexes (MSCs), however the role of such MSCs in translation is unknown. MSC function was investigated in vivo in the archaeon Thermococcus kodakarensis, wherein six aaRSs were affinity co-purified together with several other factors involved in protein synthesis, suggesting that MSCs may interact directly with translating ribosomes. In support of this hypothesis, the aminoacyltRNA synthetase (aaRS) activities of the MSC were enriched in isolated T. kodakarensis polysome fractions. These data indicate that components of the archaeal protein synthesis machinery associate into macromolecular assemblies in vivo and provide the potential …


Structural Basis For Calmodulin As A Dynamic Calcium Sensor, Miao Zhang, Cameron Abrams, Liping Wang, Anthony Gizzi, Liping He, Ruihe Lin, Yuan Chen, Patrick J. Loll, John M. Pascal, Ji-Fang Zhang May 2012

Structural Basis For Calmodulin As A Dynamic Calcium Sensor, Miao Zhang, Cameron Abrams, Liping Wang, Anthony Gizzi, Liping He, Ruihe Lin, Yuan Chen, Patrick J. Loll, John M. Pascal, Ji-Fang Zhang

Pharmacy Faculty Articles and Research

Calmodulin is a prototypical and versatile Ca2+ sensor with EF-hands as its high-affinity Ca2+ binding domains. Calmodulin is present in all eukaryotic cells, mediating Ca2+-dependent signaling. Upon binding Ca2+, calmodulin changes its conformation to form complexes with a diverse array of target proteins. Despite a wealth of knowledge on calmodulin, little is known on how target proteins regulate calmodulin’s ability to bind Ca2+. Here, we take advantage of two splice variants of SK2 channels, which are activated by Ca2+-bound calmodulin, but show different sensitivity to Ca2+ for their activation. Protein crystal structures and other experiments show that depending on which …


Selectivity Of The Ubiquitin-Binding Modules, Simin Rahighi, Ivan Dikic May 2012

Selectivity Of The Ubiquitin-Binding Modules, Simin Rahighi, Ivan Dikic

Pharmacy Faculty Articles and Research

Ubiquitin-binding modules are constituents of cellular proteins that mediate the effects of ubiquitylation by making transient, non-covalent interactions with ubiquitin molecules. While some ubiquitin- binding modules bind single ubiquitin moieties, others are selective for specific ubiquitin chains of different linkage types and lengths. In recent years, functions of ubiquitin chains that are polymerized through their Lys or N-terminal Met (i.e. linear chains) residues have been linked to a variety of cellular processes. Selectivity of ubiquitin-binding modules for different ubiquitin chain types appears as a key to the distinct regulatory consequences during protein quality control pathways, receptor endocytosis, gene transcription, signaling …


Pharmacokinetic/Pharmacodynamic (Pk/Pd) Modeling Of Anti-Neoplastic Agents, Daniel Lexcen, Ahmed H. Salem, Walid F. Elkhatib, Virginia Haynes, Ayman Noreddin Apr 2012

Pharmacokinetic/Pharmacodynamic (Pk/Pd) Modeling Of Anti-Neoplastic Agents, Daniel Lexcen, Ahmed H. Salem, Walid F. Elkhatib, Virginia Haynes, Ayman Noreddin

Pharmacy Faculty Books and Book Chapters

"Development of tumor resistance to chemotherapeutics is related to inherent tumor variations regarding sensitivity to chemotherapeutics and to sub-optimal dosing regimens, including variation in patient pharmacokinetics that result in suboptimal exposure of tumor cells to anti-neoplastic drugs [1, 2]. The rate and extent of drug efficacy depends on the extent of drug exposure at the tumor site and the time above the effective concentration [3]. In vitro models that incorporate these pharmacokinetic and pharmacodynamic (PK/PD) principles to optimize therapeutic response may be considered the method of choice for optimizing dosing schedules before translating data from static assays to animals and …


Application Of Pharmacokinetics/Pharmacodynamics (Pk/Pd) In Designing Effective Antibiotic Treatment Regimens, Ghada F. Ahmed, Ayman Noreddin Apr 2012

Application Of Pharmacokinetics/Pharmacodynamics (Pk/Pd) In Designing Effective Antibiotic Treatment Regimens, Ghada F. Ahmed, Ayman Noreddin

Pharmacy Faculty Books and Book Chapters

"Designing antibiotic dosing regimens is often not optimal and the dose-response relationship for most antibiotics is not well-known1. Both Pharmacokinetics (PK) and Pharmacodynamics (PD) are characteristics of antimicrobial agents that should be considered in the development of effective antibiotic therapy. By linking the concentration time profile at the site of action to the drug effect (PK/PD), the effect of varying dosage regimens against pathogens could be simulated enabling the identification of effective dosage strategies. It is known that inadequate antibiotic dosing could not only lead to a therapeutic failure, but also to the development of bacterial resistance. Importantly, the evolution …


Inhibition Of Adhesion And Invasion Of Pseudomonas Aeruginosa To Lung Epithelial Cells: A Model Of Cystic Fibrosis Infection, Ayman Noreddin, Ghada Sawy, Walid Elkhatib, Ehab Noreddin, Atef Shibl Mar 2012

Inhibition Of Adhesion And Invasion Of Pseudomonas Aeruginosa To Lung Epithelial Cells: A Model Of Cystic Fibrosis Infection, Ayman Noreddin, Ghada Sawy, Walid Elkhatib, Ehab Noreddin, Atef Shibl

Pharmacy Faculty Books and Book Chapters

"Over their life time, CF patients experience multiple infections by various pneumoniacausing bacteria [6]. With more patients surviving to adulthood, chronic infections with Pseudomonas aeruginosa are coming to the forefront as a leading cause of death [7]. Problems presented by infected CF lung are multi-dimensional; the electrolyte balance and pH of the fluids are abnormal. The mucus is thick and of an alternative composition compared to normal lung and may contribute to colonization with Pseudomonas aeruginosa [2, 3, 5]. As such, research is multi-pronged and includes gene therapy to correct the defective protein, amelioration of inflammatory response and thinning of …


The Mechanical Behavior Of Mutant K14-R125p Keratin Bundles And Networks In Neb-1 Keratinocytes, Daniel R. Beriault, Oualid Haddad, John V. Mccuaig, Zachary J. Robinson, David Russell, E. Birgitte Lane, Douglas S. Fudge Feb 2012

The Mechanical Behavior Of Mutant K14-R125p Keratin Bundles And Networks In Neb-1 Keratinocytes, Daniel R. Beriault, Oualid Haddad, John V. Mccuaig, Zachary J. Robinson, David Russell, E. Birgitte Lane, Douglas S. Fudge

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Epidermolysis bullosa simplex (EBS) is an inherited skin-blistering disease that is caused by dominant mutations in the genes for keratin K5 or K14 proteins. While the link between keratin mutations and keratinocyte fragility in EBS patients is clear, the exact biophysical mechanisms underlying cell fragility are not known. In this study, we tested the hypotheses that mutant K14-R125P filaments and/or networks in human keratinocytes are mechanically defective in their response to large-scale deformations. We found that mutant filaments and networks exhibit no obvious defects when subjected to large uniaxial strains and have no negative effects on the ability of human …


Cryo-Em Structure Of The Archaeal 50s Ribosomal Subunit In Complex With Initiation Factor 6 And Implications For Ribosome Evolution, Basil J. Greber, Daniel Boehringer, Vlatka Godinic-Mikulcic, Ana Crnkovic, Michael Ibba, Ivana Weygand-Durasevic, Nenad Ban Jan 2012

Cryo-Em Structure Of The Archaeal 50s Ribosomal Subunit In Complex With Initiation Factor 6 And Implications For Ribosome Evolution, Basil J. Greber, Daniel Boehringer, Vlatka Godinic-Mikulcic, Ana Crnkovic, Michael Ibba, Ivana Weygand-Durasevic, Nenad Ban

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Translation of mRNA into proteins by the ribosome is universally conserved in all cellular life. The composition and complexity of the translation machinery differ markedly between the three domains of life. Organisms from the domain Archaea show an intermediate level of complexity, sharing several additional components of the translation machinery with eukaryotes that are absent in bacteria. One of these translation factors is initiation factor 6 (IF6), which associates with the large ribosomal subunit. We have reconstructed the 50S ribosomal subunit from the archaeon Methanothermobacter thermautotrophicus in complex with archaeal IF6 at 6.6 Å resolution using cryo-electron microscopy (EM). The …


Roles Of Trna In Cell Wall Biosynthesis, Kiley Dare, Michael Ibba Jan 2012

Roles Of Trna In Cell Wall Biosynthesis, Kiley Dare, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Recent research into various aspects of bacterial metabolism such as cell wall and antibiotic synthesis, degradation pathways, cellular stress, and amino acid biosynthesis has elucidated roles of aminoacyl‐transfer ribonucleic acid (aa‐tRNA) outside of translation. Although the two enzyme families responsible for cell wall modifications, aminoacyl‐phosphatidylglycerol synthases (aaPGSs) and Fem, were discovered some time ago, they have recently become of intense interest for their roles in the antimicrobial resistance of pathogenic microorganisms. The addition of positively charged amino acids to phosphatidylglycerol (PG) by aaPGSs neutralizes the lipid bilayer making the bacteria less susceptible to positively charged antimicrobial agents. Fem transferases utilize …


Ginkgo Extract Egb761 Confers Neuroprotection By Reduction Of Glutamate Release In Ischemic Brain, Alexander Mdzinarishvili, Rachita K. Sumbria, Dorothee Lang, Jochen Klein Jan 2012

Ginkgo Extract Egb761 Confers Neuroprotection By Reduction Of Glutamate Release In Ischemic Brain, Alexander Mdzinarishvili, Rachita K. Sumbria, Dorothee Lang, Jochen Klein

Pharmacy Faculty Articles and Research

Purpose - Ginkgo extract EGb761 has shown anti-edema and anti-ischemic effects in various experimental models. In the present study, we demonstrate neuroprotective effects of EGb761 in experimental stroke while monitoring brain metabolism by microdialysis. Methods - We have used oxygen-glucose deprivation in brain slices in vitro and middle cerebral artery occlusion (MCAO) in vivo to induce ischemia in mouse brain. We used microdialysis in mouse striatum to monitor extracellular concentrations of glucose and glutamate. Results - In vitro, EGb761 reduced ischemia-induced cell swelling in hippocampal slices by 60%. In vivo, administration of EGb761 (300 mg/kg) reduced cell degeneration and edema …


Synthetic Peptides Derived From The Sequence Of A Lasso Peptide Microcin J25 Show Antibacterial Activity, Rania Soudy, Liru Wang, Kamaljit Kaur Jan 2012

Synthetic Peptides Derived From The Sequence Of A Lasso Peptide Microcin J25 Show Antibacterial Activity, Rania Soudy, Liru Wang, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Microcin J25 (MccJ25) is a plasmid-encoded, ribosomally synthesized antibacterial peptide with a unique lasso structure. The lasso structure, produced with the aid of two processing enzymes, provides exceptional stability to MccJ25. We report the synthesis of six peptides (1–6), derived from the MccJ25 sequence, that are designed to form folded conformation by disulfide bond formation and electrostatic or hydrophobic interactions. Two peptides (1 and 6) display good activity against Salmonella newport, and are the first synthetic derivatives of MccJ25 that are bactericidal. Peptide 1 displays potent activity against several Salmonella strains including two …


Effective Non-Viral Delivery Of Sirna To Acute Myeloid Leukemia Cells With Lipid-Substituted Polyethylenimines, Breanne Landry Jan 2012

Effective Non-Viral Delivery Of Sirna To Acute Myeloid Leukemia Cells With Lipid-Substituted Polyethylenimines, Breanne Landry

Pharmacy Faculty Articles and Research

Use of small interfering RNA (siRNA) is a promising approach for AML treatment as the siRNA molecule can be designed to specifically target proteins that contribute to aberrant cell proliferation in this disease. However, a clinical-relevant means of delivering siRNA molecules must be developed, as the cellular delivery of siRNA is problematic. Here, we report amphiphilic carriers combining a cationic polymer (2 kDa polyethyleneimine, PEI2) with lipophilic moieties to facilitate intracellular delivery of siRNA to AML cell lines. Complete binding of siRNA by the designed carriers was achieved at a polymer:siRNA ratio of ~0.5 and led to siRNA/polymer complexes of …