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Articles 31 - 60 of 404

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

Abstract 2587 Recombinant Expression And Purification Of A. Vinelandii Cown In E. Coli, Julie Takei, Cedric P. Owens, Katie Sanders, Neeraja Gajendran Jun 2025

Abstract 2587 Recombinant Expression And Purification Of A. Vinelandii Cown In E. Coli, Julie Takei, Cedric P. Owens, Katie Sanders, Neeraja Gajendran

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The goal of this project is to study the protein CowN in the diazotroph Azotobacter vinelandii (Av) in comparison to CowN in Gluconacetobacter diazotrophicus (Gd). Nitrogenase is an enzyme that catalyzes the reduction of nitrogen gas into ammonia in diazotrophic bacteria. In many diazotrophs, the protein CowN prevents nitrogenase inhibition from the environmental gas carbon monoxide (CO). Previous work studied CowN in the diazotroph G. diazotrophicus. In G. diazotrophicus, CowN binds to nitrogenase and weakens CO binding to its active site. The mechanism of CowN has only been investigated in G. diazotrophicus. Thus, we are interested in determining if CowN's …


Abstract 2853 Prmt7 Negatively Regulates The Expression P53 In Response To Dna Damage, Molly Niswender, Lorenzo Pessi, Cecilia Lopez, Marco Bisoffi Jun 2025

Abstract 2853 Prmt7 Negatively Regulates The Expression P53 In Response To Dna Damage, Molly Niswender, Lorenzo Pessi, Cecilia Lopez, Marco Bisoffi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Protein Arginine Methyltransferase 7 (PRMT7) is the only member of the protein arginine methyltransferase protein family that monomethylates its protein substrates. PRMT7 is found in both the nucleus and cytoplasm of breast cells and is believed to play a robust role in the tumorigenesis and metastasis of breast cancer. The goal of this project is to uncover possible pathways for PRMT7 to promote cancer progression. A preliminary antibody array was performed to determine the regulation of known cancer-related proteins by PRMT7. An early-stage human breast cancer cell line, MCF-7, was transfected with plasmid pCDH1-hPRMT7-GFP to over-express PRMT7. Qualitative and quantitative …


Ensemble-Based Binding Free Energy Profiling And Network Analysis Of The Kras Interactions With Darpin Proteins Targeting Distinct Binding Sites: Revealing Molecular Determinants And Universal Architecture Of Regulatory Hotspots And Allosteric Binding, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Gennady M. Verkhivker Jun 2025

Ensemble-Based Binding Free Energy Profiling And Network Analysis Of The Kras Interactions With Darpin Proteins Targeting Distinct Binding Sites: Revealing Molecular Determinants And Universal Architecture Of Regulatory Hotspots And Allosteric Binding, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

KRAS is a pivotal oncoprotein that regulates cell proliferation and survival through interactions with downstream effectors such as RAF1. Despite significant advances in understanding KRAS biology, the structural and dynamic mechanisms of KRAS allostery remain poorly understood. In this study, we employ microsecond molecular dynamics simulations, mutational scanning, and binding free energy calculations together with dynamic network modeling to dissect how engineered DARPin proteins K27, K55, K13, and K19 engage KRAS through diverse molecular mechanisms ranging from effector mimicry to conformational restriction and allosteric modulation. Mutational scanning across all four DARPin systems identifies a core set of evolutionarily constrained residues …


Integrative Computational Modeling Of Distinct Binding Mechanisms For Broadly Neutralizing Antibodies Targeting Sars-Cov-2 Spike Omicron Variants: Balance Of Evolutionary And Dynamic Adaptability In Shaping Molecular Determinants Of Immune Escape, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Gennady M. Verkhivker May 2025

Integrative Computational Modeling Of Distinct Binding Mechanisms For Broadly Neutralizing Antibodies Targeting Sars-Cov-2 Spike Omicron Variants: Balance Of Evolutionary And Dynamic Adaptability In Shaping Molecular Determinants Of Immune Escape, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this study, we conducted a comprehensive analysis of the interactions between the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein and four neutralizing antibodies—S309, S304, CYFN1006, and VIR-7229. Using integrative computational modeling that combined all-atom molecular dynamics (MD) simulations, mutational scanning, and MM-GBSA binding free energy calculations, we elucidated the structural, energetic, and dynamic determinants of antibody binding. Our findings reveal distinct dynamic binding mechanisms and evolutionary adaptation driving the broad neutralization effect of these antibodies. We show that S309 targets conserved residues near the ACE2 interface, leveraging synergistic van der Waals and electrostatic interactions, while S304 focuses on …


Probing Binding And Allosteric Mechanisms Of The Kras Interactions With Monobodies And Affimer Proteins : Ensemble-Based Mutational Profiling And Thermodynamic Analysis Of Binding Energetics And Allostery Reveal Diversity Of Functional Hotspots And Cryptic Pockets Linked By Conserved Communication Network, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Guang Hu, Gennady M. Verkhivker May 2025

Probing Binding And Allosteric Mechanisms Of The Kras Interactions With Monobodies And Affimer Proteins : Ensemble-Based Mutational Profiling And Thermodynamic Analysis Of Binding Energetics And Allostery Reveal Diversity Of Functional Hotspots And Cryptic Pockets Linked By Conserved Communication Network, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Guang Hu, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

KRAS, a historically "undruggable" oncogenic driver, has eluded targeted therapies due to its lack of accessible binding pockets in its active state. This study investigates the conformational dynamics, binding mechanisms, and allosteric communication networks of KRAS in complexes with monobodies (12D1, 12D5) and affimer proteins (K6, K3, K69) to characterize the binding and allosteric mechanisms and hotspots of KRAS binding. Through molecular dynamics simulations, mutational scanning, binding free energy analysis and network-based analyses, we identified conserved allosteric hotspots that serve as critical nodes for long-range communication in KRAS. Key residues in β-strand 4 (F78, L80, F82), α-helix 3 (I93, H95, …


Ocular Surface Glycocalyx In Health And Disease, Rafael Martínez-Carrasco, Ajay Sharma Mar 2025

Ocular Surface Glycocalyx In Health And Disease, Rafael Martínez-Carrasco, Ajay Sharma

Pharmacy Faculty Articles and Research

The glycocalyx is a dynamic carbohydrate-enriched structure that forms a dense coating on the surface of animal cells, including those at the ocular surface. It plays a critical role in maintaining cellular functions and it has a significant influence in disease processes. At the ocular surface, glycoproteins such as mucins are essential for hydration, lubrication, and barrier protection. Proteoglycans and glycolipids contribute to cell signaling, and mediate interactions with pathogens. Alterations in the glycocalyx are implicated in a spectrum of ocular conditions, including dry eye disease, ocular allergies, infections, and systemic diseases such as Graft-versus-host disease (GVHD) and diabetes mellitus. …


Quantitative Characterization And Prediction Of The Binding Determinants And Immune Escape Hotspots For Groups Of Broadly Neutralizing Antibodies Against Omicron Variants: Atomistic Modeling Of The Sars-Cov-2 Spike Complexes With Antibodies, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Nishank Raisinghani, Gennady M. Verkhivker Feb 2025

Quantitative Characterization And Prediction Of The Binding Determinants And Immune Escape Hotspots For Groups Of Broadly Neutralizing Antibodies Against Omicron Variants: Atomistic Modeling Of The Sars-Cov-2 Spike Complexes With Antibodies, Mohammed Alshahrani, Vedant Parikh, Brandon Foley, Nishank Raisinghani, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

A growing body of experimental and computational studies suggests that the cross-neutralization antibody activity against Omicron variants may be driven by the balance and tradeoff between multiple energetic factors and interaction contributions of the evolving escape hotspots involved in antigenic drift and convergent evolution. However, the dynamic and energetic details quantifying the balance and contribution of these factors, particularly the balancing nature of specific interactions formed by antibodies with epitope residues, remain largely uncharacterized. In this study, we performed molecular dynamics simulations, an ensemble-based deep mutational scanning of SARS-CoV-2 spike residues, and binding free energy computations for two distinct groups …


Orchestrating Cytosolic Access: The Partnership Of Cationic Lytic Peptide L17e And Potassium Channel Kca3.1, Keykavous Parang Jan 2025

Orchestrating Cytosolic Access: The Partnership Of Cationic Lytic Peptide L17e And Potassium Channel Kca3.1, Keykavous Parang

Pharmacy Faculty Articles and Research

In this issue of Molecular Therapy, the study by Kuriyama et al.1 represents an advance in the field of intracellular delivery systems by elucidating a novel mechanism for cytosolic delivery mediated by a cationic amphiphilic lytic peptide L17E (IWLTALKFLGKHAAKHEAKQQLSKL-amide). The investigators demonstrate that the peptide achieves cytosolic delivery primarily through transient plasma membrane disruption, bypassing some of the endocytic pathways, and highlight the pivotal role of the calcium-activated potassium channel KCa3.1, encoded by the gene KCNN4, in facilitating this process. These findings offer a deeper understanding of peptide-mediated delivery using a potassium channel and raise intriguing questions about …


Uncovering The Binding Mechanism Of Mutated Omicron Variants Via Computational Strategies, Sajjad Haider, Nadeem Ahmad, Muhammad Shafiq, Ali Raza Siddiqui, Mohammad Nur-E-Alam, Aftab Ahmed, Zaheer Ul-Haq Jan 2025

Uncovering The Binding Mechanism Of Mutated Omicron Variants Via Computational Strategies, Sajjad Haider, Nadeem Ahmad, Muhammad Shafiq, Ali Raza Siddiqui, Mohammad Nur-E-Alam, Aftab Ahmed, Zaheer Ul-Haq

Pharmacy Faculty Articles and Research

The COVID-19 pandemic, triggered by the SARS-CoV-2 virus, has resulted in nearly 630 million cases and 6.60 million fatalities globally, as of November 2022. SARS-CoV-2, a species of the Coronaviridae family, has a single-stranded positive-sense RNA genome as well as four main structural proteins (S, E, M, and N) required for viral entrance into target cells. The spike protein (S) influences this entry through interactions with human angiotensin-converting enzyme 2 (hACE2) receptor. The World Health Organization (WHO) recognized numerous variants of concern (VOCs) that involve Alpha, Beta, Gamma, Delta, and Omicron, having multiple mutations within the spike protein, altering infection …


Tdp43 Autoregulation Gives Rise To Dominant Negative Isoforms That Are Tightly Controlled By Transcriptional And Post-Translational Mechanisms, Megan M. Dykstra, Kaitlin Weskamp, Nicolás B. Gómez, Jacob Waksmacki, Elizabeth Tank, M. Rebecca Glineburg, Allison Snyder, Emile Pinarbasi, Michael Bekier, Xingli Li, Morgan R. Miller, Jen Bai, Shameena Shahzad, Neha Nedumaran, Clare Wieland, Corey Stewart, Sydney Willey, Nikolas Grotewold, Jonathon Mcbride, John J. Moran, Aditya V. Suryakumar, Michael Lucas, Peter M. Tessier, Michael Ward, Peter K. Todd, Sami J. Barmada Jan 2025

Tdp43 Autoregulation Gives Rise To Dominant Negative Isoforms That Are Tightly Controlled By Transcriptional And Post-Translational Mechanisms, Megan M. Dykstra, Kaitlin Weskamp, Nicolás B. Gómez, Jacob Waksmacki, Elizabeth Tank, M. Rebecca Glineburg, Allison Snyder, Emile Pinarbasi, Michael Bekier, Xingli Li, Morgan R. Miller, Jen Bai, Shameena Shahzad, Neha Nedumaran, Clare Wieland, Corey Stewart, Sydney Willey, Nikolas Grotewold, Jonathon Mcbride, John J. Moran, Aditya V. Suryakumar, Michael Lucas, Peter M. Tessier, Michael Ward, Peter K. Todd, Sami J. Barmada

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The nuclear RNA-binding protein TDP43 is integrally involved in the pathogenesis of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Previous studies uncovered N-terminal TDP43 isoforms that are predominantly cytosolic in localization, prone to aggregation, and enriched in susceptible spinal motor neurons. In healthy cells, however, these shortened (s)TDP43 isoforms are difficult to detect in comparison to full-length (fl)TDP43, raising questions regarding their origin and selective regulation. Here, we show that sTDP43 is created as a by-product of TDP43 autoregulation and cleared by nonsense-mediated RNA decay (NMD). sTDP43-encoding transcripts that escape NMD are rapidly degraded post-translationally via the proteasome …


Brain Delivery Of Erythropoietin Results In A Significant Reduction Of Brain Aβ And Spatial Memory Deficits In The App Knock-In Mouse Model, Rudy Tieu Chang, Devaraj V. Chandrashekar, Grace-Ann Chuli Roules, Emi Iwasaki, Nataraj Jagadeesan, Rachita K. Sumbria Jan 2025

Brain Delivery Of Erythropoietin Results In A Significant Reduction Of Brain Aβ And Spatial Memory Deficits In The App Knock-In Mouse Model, Rudy Tieu Chang, Devaraj V. Chandrashekar, Grace-Ann Chuli Roules, Emi Iwasaki, Nataraj Jagadeesan, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Although novel treatments for Alzheimer’s disease (AD) have begun to show modest therapeutic effects, agents that target hallmark AD pathology and offer neuroprotection are desired. Erythropoietin (EPO) is a glycoprotein hormone with neuroprotective effects but is faced with challenges including limited brain uptake and increased hematopoietic side effects with long-term dosing. Therefore, EPO has been modified and bound to a chimeric transferrin receptor monoclonal antibody (cTfRMAb); the latter shuttles EPO past the blood-brain barrier (BBB) into brain parenchyma and reduces its plasma exposure and potential for side effects. Our study sought to characterize the safety and pharmacokinetics (PK) of …


Two-Year Follow-Up Of Gait And Postural Control Following Initiation Of Recombinant Human Tripeptidyl Intracerebroventricular Enzyme Replacement Therapy In Two Atypical Cln2 Patients, Rahul Soangra, Marybeth Grant-Beuttler, Harriet Chang, Raymond Y. Wang Jan 2025

Two-Year Follow-Up Of Gait And Postural Control Following Initiation Of Recombinant Human Tripeptidyl Intracerebroventricular Enzyme Replacement Therapy In Two Atypical Cln2 Patients, Rahul Soangra, Marybeth Grant-Beuttler, Harriet Chang, Raymond Y. Wang

Physical Therapy Faculty Articles and Research

Neuronal ceroid lipofuscinosis type 2 (CLN2) is a rapidly progressive neurodegenerative disorder leading to premature mortality. Ambulatory CLN2 patients typically receive standard of care treatment through biweekly intracerebroventricular (ICV) enzyme replacement therapy (ERT) involving recombinant human tripeptidyl peptidase 1, known as cerliponase alfa (Brineura®, Biomarin Pharmaceuticals). This study longitudinally assessed the impact of ICV cerliponase alfa ERT on gait, and postural control across a two-year span in two siblings diagnosed with atypical CLN2 disease. Both participants, ID01 (18 years and 8 months old at enrollment) and ID02 (13 years and 3 months old at enrollment), exhibited symptomatic characteristics …


Proteoglycan 4 (Lubricin) And Regulation Of Xanthine Oxidase In Synovial Macrophage As A Mechanism Of Controlling Synovitis, Khaled A. Elsaid, Ling X. Zhang, Thomas Zhao, Ava Marks, Derek Jenkins, Tannin A. Schmidt, Gregory D. Jay Dec 2024

Proteoglycan 4 (Lubricin) And Regulation Of Xanthine Oxidase In Synovial Macrophage As A Mechanism Of Controlling Synovitis, Khaled A. Elsaid, Ling X. Zhang, Thomas Zhao, Ava Marks, Derek Jenkins, Tannin A. Schmidt, Gregory D. Jay

Pharmacy Faculty Articles and Research

Background

Synovial macrophages (SMs) are important effectors of joint health and disease. A novel Cx3CR1 + TREM2 + SM population expressing the tight junction protein claudin-5, was recently discovered in synovial lining. Ablation of these SMs was associated with onset of arthritis. Proteoglycan 4 (PRG4) is a mucinous glycoprotein that fulfills lubricating and homeostatic roles in the joint. The aim of this work is to study the role of PRG4 in modulating synovitis in the context of SM homeostasis and assess the contribution of xanthine oxidase (XO)-hypoxia inducible factor alpha (HIF-1a) axis to this regulation.

Methods

We used Prg4FrtloxP/FrtloxP …


A Conjugate Of An Egfr-Binding Peptide And Doxorubicin Shows Selective Toxicity To Triple-Negative Breast Cancer Cells, Phi-Phung Than, Shih-Jing Yao, Emad Althagafi, Kamaljit Kaur Dec 2024

A Conjugate Of An Egfr-Binding Peptide And Doxorubicin Shows Selective Toxicity To Triple-Negative Breast Cancer Cells, Phi-Phung Than, Shih-Jing Yao, Emad Althagafi, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Selective targeting of cancer cells via overexpressed cell-surface receptors is a promising strategy to enhance chemotherapy efficacy and minimize off-target side effects. In this study, we designed peptide 31 (YHWYGYTPERVI) to target the overexpressed epidermal growth factor receptor (EGFR) in triple-negative breast cancer (TNBC) cells. Peptide 31 is internalized by TNBC cells through EGFR-mediated endocytosis and shares sequence and structural similarities with human EGF (hEGF), a natural EGFR ligand. Unlike hEGF, peptide 31 does not induce cell migration in TNBC cells. A novel conjugate of peptide 31 with doxorubicin (Dox) retains selectivity for TNBC cells and exhibits significant toxicity comparable …


Alphafold2-Based Characterization Of Apo And Holo Protein Structures And Conformational Ensembles Using Randomized Alanine Sequence Scanning Adaptation: Capturing Shared Signature Dynamics And Ligand-Induced Conformational Changes, Nishank Raisinghani, Vedant Parikh, Brandon Foley, Gennady M. Verkhivker Dec 2024

Alphafold2-Based Characterization Of Apo And Holo Protein Structures And Conformational Ensembles Using Randomized Alanine Sequence Scanning Adaptation: Capturing Shared Signature Dynamics And Ligand-Induced Conformational Changes, Nishank Raisinghani, Vedant Parikh, Brandon Foley, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Proteins often exist in multiple conformational states, influenced by the binding of ligands or substrates. The study of these states, particularly the apo (unbound) and holo (ligand-bound) forms, is crucial for understanding protein function, dynamics, and interactions. In the current study, we use AlphaFold2, which combines randomized alanine sequence masking with shallow multiple sequence alignment subsampling to expand the conformational diversity of the predicted structural ensembles and capture conformational changes between apo and holo protein forms. Using several well-established datasets of structurally diverse apo-holo protein pairs, the proposed approach enables robust predictions of apo and holo structures and conformational ensembles, …


Unravelling The Erythropoietin Heterodimeric Complex: In Silico Analysis Of Complex Assembly And Binding Interface, Atiya Habib, Urooj Qureshi, Mohammad Nur-E-Alam, Aftab Ahmed, Zaheer Ul-Haq Nov 2024

Unravelling The Erythropoietin Heterodimeric Complex: In Silico Analysis Of Complex Assembly And Binding Interface, Atiya Habib, Urooj Qureshi, Mohammad Nur-E-Alam, Aftab Ahmed, Zaheer Ul-Haq

Pharmacy Faculty Articles and Research

Erythropoietin (Epo), a glycosylated protein categorized as a member of the cytokine family, is responsible for the modulation of erythrogenesis. Besides this, the nonhaematopoietic effects of Epo are associated with tissue-protective activity via an antiapoptotic pathway. This function of Epo is linked with its heterodimeric form, i.e. EpoR/βcR belonging to the cytokine family as well. Both receptors are dissected into three domains: extracellular (also known as ligand-binding domain), transmembrane and cytoplasmic domain. The transmembrane and cytoplasmic domains are assumed to play a paramount role in dimerization and tissue protection. However, the tertiary structure of cytoplasmic domains of both …


Synthesis And Evaluation Of Cyclic Peptide-Dasatinib Conjugates As Anti-Melanoma Agents, Shaban Darwish, Dorna Davani-Davari, Shirley Tong, Rakesh Kumar Tiwari, Sun Yang, Keykavous Parang Nov 2024

Synthesis And Evaluation Of Cyclic Peptide-Dasatinib Conjugates As Anti-Melanoma Agents, Shaban Darwish, Dorna Davani-Davari, Shirley Tong, Rakesh Kumar Tiwari, Sun Yang, Keykavous Parang

Pharmacy Faculty Articles and Research

Herein, we synthesized two amphiphilic cyclic peptides, incorporating tryptophan and arginine residues, linked to dasatinib via a Cathepsin B-sensitive tetrapeptide (Gly-Phe-Leu-Gly). To mitigate steric hindrance and optimize drug release, we integrated two different linkers, succinate and glutarate, between the drug and peptide. The synthesis involved solid-phase techniques for the assembly of the peptide, followed by the coupling of the peptide on-resin with the linker, mild cleavage, and solution-phase cyclization. Conjugation of the peptide-attached linker with dasatinib was conducted in the presence of N-methylmorpholine and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), generating the novel prodrugs. The synthesized compounds were characterized by high-resolution mass …


Identification Of New Leads Against Ubiquitin Specific Protease-7 (Usp7): A Step Towards The Potential Treatment Of Cancers, Sumaira Javaid, Seema Zadi, Muhammad Awais, Atai-Tul Wahab, Humaira Zafar, Innokentiy Maslennikov, M. Iqbal Choudhary Oct 2024

Identification Of New Leads Against Ubiquitin Specific Protease-7 (Usp7): A Step Towards The Potential Treatment Of Cancers, Sumaira Javaid, Seema Zadi, Muhammad Awais, Atai-Tul Wahab, Humaira Zafar, Innokentiy Maslennikov, M. Iqbal Choudhary

Pharmacy Faculty Articles and Research

Ubiquitin-specific protease-7 (USP7) is an important drug target as it regulates multiple proteins and genes (such as MDM2 and p53) with roles in cancer progression. Its inhibition can hinder the function of oncogenes, increase tumor suppression, and enhance immune response. The current study was designed to express USP7 in a prokaryotic system, followed by screening of small molecules against it using biophysical methods, primarily STD-NMR technique. Among them, 12 compounds showed interaction with USP7 as inferred from NMR-based screening. These compounds further caused destabilization of USP7 by reducing its melting temperature (Tm) up to 6 °C in …


The Role Of Peptides In Combatting Hiv Infection: Applications And Insights, Naiera M. Helmy, Keykavous Parang Oct 2024

The Role Of Peptides In Combatting Hiv Infection: Applications And Insights, Naiera M. Helmy, Keykavous Parang

Pharmacy Faculty Articles and Research

Peptide-based inhibitors represent a promising approach for the treatment of HIV-1, offering a range of potential advantages, including specificity, low toxicity, and the ability to target various stages of the viral lifecycle. This review outlines the current state of research on peptide-based anti-HIV therapies, highlighting key advancements and identifying future research directions. Over the past few years, there has been significant progress in developing synthetic peptide-based drugs that target various stages of the viral life cycle, including entry and replication. These approaches aim to create effective anti-HIV therapies. Additionally, peptides have proven valuable in the development of anti-HIV vaccines. In …


Predicting Mutation-Induced Allosteric Changes In Structures And Conformational Ensembles Of The Abl Kinase Using Alphafold2 Adaptations With Alanine Sequence Scanning, Nishank Raisinghani, Mohammed Alshahrani, Grace Gupta, Gennady M. Verkhivker Sep 2024

Predicting Mutation-Induced Allosteric Changes In Structures And Conformational Ensembles Of The Abl Kinase Using Alphafold2 Adaptations With Alanine Sequence Scanning, Nishank Raisinghani, Mohammed Alshahrani, Grace Gupta, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Despite the success of AlphaFold2 approaches in predicting single protein structures, these methods showed intrinsic limitations in predicting multiple functional conformations of allosteric proteins and have been challenged to accurately capture the effects of single point mutations that induced significant structural changes. We examined several implementations of AlphaFold2 methods to predict conformational ensembles for state-switching mutants of the ABL kinase. The results revealed that a combination of randomized alanine sequence masking with shallow multiple sequence alignment subsampling can significantly expand the conformational diversity of the predicted structural ensembles and capture shifts in populations of the active and inactive ABL states. …


Alphafold2 Modeling And Molecular Dynamics Simulations Of The Conformational Ensembles For The Sars-Cov-2 Spike Omicron Jn.1, Kp.2 And Kp.3 Variants: Mutational Profiling Of Binding Energetics Reveals Epistatic Drivers Of The Ace2 Affinity And Escape Hotspots Of Antibody Resistance, Nishank Raisinghani, Mohammed Alshahrani, Grace Gupta, Gennady M. Verkhivker Sep 2024

Alphafold2 Modeling And Molecular Dynamics Simulations Of The Conformational Ensembles For The Sars-Cov-2 Spike Omicron Jn.1, Kp.2 And Kp.3 Variants: Mutational Profiling Of Binding Energetics Reveals Epistatic Drivers Of The Ace2 Affinity And Escape Hotspots Of Antibody Resistance, Nishank Raisinghani, Mohammed Alshahrani, Grace Gupta, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

AlphaFold2-based atomistic predictions of structures and conformational ensembles of the SARS-CoV-2 spike complexes with the host receptor ACE2 for the most dominant Omicron variants JN.1, KP.1, KP.2 and KP.3 to examine the mechanisms underlying the role of convergent evolution hotspots in balancing ACE2 binding and antibody evasion. Using the ensemble-based mutational scanning of the spike protein residues and computations of binding affinities, we identified binding energy hotspots and characterized the molecular basis underlying epistatic couplings between convergent mutational hotspots. The results suggested the existence of epistatic interactions between convergent mutational sites at L455, F456, Q493 positions that protect and restore …


Aars Online: A Collaborative Database On The Structure, Function, And Evolution Of The Aminoacyl-Trna Synthetases, Jordan Douglas, Haissi Cui, John J. Perona, Oscar Vargas-Rodriguez, Henna Tyynismaa, Claudia Alvarez Carreño, Jiqiang Ling, Lluís Ribas De Pouplana, Xiang-Lei Yang, Michael Ibba, Hubert Becker, Frédéric Fischer, Marie Sissler, Charles W. Carter Jr., Peter Wills Sep 2024

Aars Online: A Collaborative Database On The Structure, Function, And Evolution Of The Aminoacyl-Trna Synthetases, Jordan Douglas, Haissi Cui, John J. Perona, Oscar Vargas-Rodriguez, Henna Tyynismaa, Claudia Alvarez Carreño, Jiqiang Ling, Lluís Ribas De Pouplana, Xiang-Lei Yang, Michael Ibba, Hubert Becker, Frédéric Fischer, Marie Sissler, Charles W. Carter Jr., Peter Wills

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The aminoacyl-tRNA synthetases (aaRS) are a large group of enzymes that implement the genetic code in all known biological systems. They attach amino acids to their cognate tRNAs, moonlight in various translational and non-translational activities beyond aminoacylation, and are linked to many genetic disorders. The aaRS have a subtle ontology characterized by structural and functional idiosyncrasies that vary from organism to organism, and protein to protein. Across the tree of life, the 22 coded amino acids are handled by 16 evolutionary families of Class I aaRS and 21 families of Class II aaRS. We introduce AARS Online, an interactive Wikipedia-like …


Design, Synthesis, And Evaluation Of Oleyl-Wrh Peptides For Sirna Delivery, Mrigank Shekhar Rai, Muhammad Imran Sajid, Jonathan Moreno, Keykavous Parang, Rakesh Kumar Tiwari Aug 2024

Design, Synthesis, And Evaluation Of Oleyl-Wrh Peptides For Sirna Delivery, Mrigank Shekhar Rai, Muhammad Imran Sajid, Jonathan Moreno, Keykavous Parang, Rakesh Kumar Tiwari

Pharmacy Faculty Articles and Research

Delivering nucleic acid therapeutics across cell membranes is a significant challenge. Cell-penetrating peptides (CPPs) containing arginine (R), tryptophan (W), and histidine (H) show promise for siRNA delivery. To improve siRNA delivery and silence a model STAT3 gene, we hypothesized that oleyl acylation to CPPs, specifically (WRH)n, would enhance STAT3 silencing efficiency in breast and ovarian cancer cells. Using Fmoc/tBu solid-phase peptide chemistry, we synthesized, purified, and characterized the oleyl-conjugated (WRH)n (n = 1–4) peptides. The peptide/siRNA complexes were non-cytotoxic at N/P 40 (~20 μM) against MDA-MB-231, MCF-7, SK-OV-3, and HEK-293 cells after 72 h incubation. All peptide/siRNA complexes showed serum …


Stress Granule Formation Helps To Mitigate Neurodegeneration, M. Rebecca Glineburg, Evrim Yildirim, Nicolas Gomez, Genesis Rodriguez, Jaclyn Pak, Xingli Li, Christopher Altheim, Jacob Waksmacki, Gerald M. Mcinerney, Sami J. Barmada, Peter K. Todd Aug 2024

Stress Granule Formation Helps To Mitigate Neurodegeneration, M. Rebecca Glineburg, Evrim Yildirim, Nicolas Gomez, Genesis Rodriguez, Jaclyn Pak, Xingli Li, Christopher Altheim, Jacob Waksmacki, Gerald M. Mcinerney, Sami J. Barmada, Peter K. Todd

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Cellular stress pathways that inhibit translation initiation lead to transient formation of cytoplasmic RNA/protein complexes known as stress granules. Many of the proteins found within stress granules and the dynamics of stress granule formation and dissolution are implicated in neurodegenerative disease. Whether stress granule formation is protective or harmful in neurodegenerative conditions is not known. To address this, we took advantage of the alphavirus protein nsP3, which selectively binds dimers of the central stress granule nucleator protein G3BP and markedly reduces stress granule formation without directly impacting the protein translational inhibitory pathways that trigger stress granule formation. In Drosophila and …


Diesel Exhaust Particles Alter Mitochondrial Bioenergetics And Camp Producing Capacity In Human Bronchial Epithelial Cells, Isabella Cattani-Cavalieri, Marina Trombetta-Lima, Hong Yan, Ana L. Manzano-Covarrubias, Hoeke A. Baarsma, Asmaa Oun, Melissa Mol Van Der Veen, Emily Oosterhout, Amalia M. Dolga, Rennolds S. Ostrom, Samuel Santos Valenca, Martina Schmidt Jul 2024

Diesel Exhaust Particles Alter Mitochondrial Bioenergetics And Camp Producing Capacity In Human Bronchial Epithelial Cells, Isabella Cattani-Cavalieri, Marina Trombetta-Lima, Hong Yan, Ana L. Manzano-Covarrubias, Hoeke A. Baarsma, Asmaa Oun, Melissa Mol Van Der Veen, Emily Oosterhout, Amalia M. Dolga, Rennolds S. Ostrom, Samuel Santos Valenca, Martina Schmidt

Pharmacy Faculty Articles and Research

Introduction: Air pollution from diesel combustion is linked in part to the generation of diesel exhaust particles (DEP). DEP exposure induces various processes, including inflammation and oxidative stress, which ultimately contribute to a decline in lung function. Cyclic AMP (cAMP) signaling is critical for lung homeostasis. The impact of DEP on cAMP signaling is largely unknown.

Methods: We exposed human bronchial epithelial (BEAS-2B) cells to DEP for 24–72 h and evaluated mitochondrial bioenergetics, markers of oxidative stress and inflammation and the components of cAMP signaling. Mitochondrial bioenergetics was measured at 72 h to capture the potential and accumulative effects of …


Mechanistic Study Of Antimicrobial Effectiveness Of Cyclic Amphipathic Peptide [R4W4] Against Methicillin-Resistant Staphylococcus Aureus Clinical Isolates, Ajayi David Akinwale, Keykavous Parang, Rakesh Kumar Tiwari, Jason Yamaki Jun 2024

Mechanistic Study Of Antimicrobial Effectiveness Of Cyclic Amphipathic Peptide [R4W4] Against Methicillin-Resistant Staphylococcus Aureus Clinical Isolates, Ajayi David Akinwale, Keykavous Parang, Rakesh Kumar Tiwari, Jason Yamaki

Pharmacy Faculty Articles and Research

Antimicrobial peptides (AMPs) are being explored as a potential strategy to combat antibiotic resistance due to their ability to reduce susceptibility to antibiotics. This study explored whether the [R4W4] peptide mode of action is bacteriostatic or bactericidal using modified two-fold serial dilution and evaluating the synergism between gentamicin and [R4W4] against Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA) by a checkered board assay. [R4W4] exhibited bactericidal activity against bacterial isolates (MBC/MIC ≤ 4), with a synergistic effect with gentamicin against E. coli (FICI = 0.3) but …


Proteomic Characterization And Cytotoxic Potential Of Proteins From Cuscuta (Cuscuta Epithymum (L.) Crude Herbal Product Against Mcf-7 Human Breast Cancer Cell Line, Umaima Akhtar, Yamna Khurshid, Bishoy El-Aarag, Basir Syed, Ishtiaq A. Khan, Keykavous Parang, Aftab Ahmed May 2024

Proteomic Characterization And Cytotoxic Potential Of Proteins From Cuscuta (Cuscuta Epithymum (L.) Crude Herbal Product Against Mcf-7 Human Breast Cancer Cell Line, Umaima Akhtar, Yamna Khurshid, Bishoy El-Aarag, Basir Syed, Ishtiaq A. Khan, Keykavous Parang, Aftab Ahmed

Pharmacy Faculty Articles and Research

Background

The burden of breast cancer, the second leading cause of death worldwide, is increasing at an alarming rate. Cuscuta, used in traditional medicine for different ailments, including cancer, is known for containing phytochemicals that exhibit anticancer activity; however, the bioactivities of proteins from this plant remain unexplored. This study aimed to screen the cytotoxic potential of proteins from the crude herbal product of Cuscuta epithymum(L.) (CE) harvested from the host plants Alhagi maurorum and Medicago sativa.

Methods

The proteins from CE were extracted using a salting-out method, followed by fractionation with a gel filtration chromatography column. Gel-free shotgun …


Amphipathic Hybrid Cyclic-Linear Peptides As A Drug Delivery System, Jonathan Moreno May 2024

Amphipathic Hybrid Cyclic-Linear Peptides As A Drug Delivery System, Jonathan Moreno

Pharmaceutical Sciences (PhD) Dissertations

Amphipathic Hybrid Cyclic-Linear Peptides as a Drug Delivery System by Jonathan A. Moreno Peptides

[RW]4 and [R5W4] have been previously identified as molecular transporter Cell Penetrating Peptide (CPP) and antimicrobial agents, respectively. These peptides consisted of alternating and non-alternating arginine (R) as positively charged residues and tryptophan (W) as hydrophobic residues. Herein we report the synthesis of two hybrid amphipathic cyclic-linear cell-penetrating peptides [RW]4K-AH135 (1) and [R5W4]K-AH135 (2) composed of [RW]4 and [R5W4] and a linear peptide AH-135 (Ac)NH-RWLRRWLRWWRR-COOH. The …


Exploring Binding Pockets In The Conformational States Of The Sars-Cov-2 Spike Trimers For The Screening Of Allosteric Inhibitors Using Molecular Simulations And Ensemble-Based Ligand Docking, Grace Gupta, Gennady M. Verkhivker May 2024

Exploring Binding Pockets In The Conformational States Of The Sars-Cov-2 Spike Trimers For The Screening Of Allosteric Inhibitors Using Molecular Simulations And Ensemble-Based Ligand Docking, Grace Gupta, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Understanding mechanisms of allosteric regulation remains elusive for the SARS-CoV-2 spike protein, despite the increasing interest and effort in discovering allosteric inhibitors of the viral activity and interactions with the host receptor ACE2. The challenges of discovering allosteric modulators of the SARS-CoV-2 spike proteins are associated with the diversity of cryptic allosteric sites and complex molecular mechanisms that can be employed by allosteric ligands, including the alteration of the conformational equilibrium of spike protein and preferential stabilization of specific functional states. In the current study, we combine conformational dynamics analysis of distinct forms of the full-length spike protein trimers and …


Predicting Ffar4 Agonists Using Structure-Based Machine Learning Approach Based On Molecular Fingerprints, Zaid Anis Sherwani, Syeda Sumayya Tariq, Mamona Mushtaq, Ali Raza Siddiqui, Mohammad Nur-E-Alam, Aftab Ahmed, Zaheer Ul-Haq Apr 2024

Predicting Ffar4 Agonists Using Structure-Based Machine Learning Approach Based On Molecular Fingerprints, Zaid Anis Sherwani, Syeda Sumayya Tariq, Mamona Mushtaq, Ali Raza Siddiqui, Mohammad Nur-E-Alam, Aftab Ahmed, Zaheer Ul-Haq

Pharmacy Faculty Articles and Research

Free Fatty Acid Receptor 4 (FFAR4), a G-protein-coupled receptor, is responsible for triggering intracellular signaling pathways that regulate various physiological processes. FFAR4 agonists are associated with enhancing insulin release and mitigating the atherogenic, obesogenic, pro-carcinogenic, and pro-diabetogenic effects, normally associated with the free fatty acids bound to FFAR4. In this research, molecular structure-based machine-learning techniques were employed to evaluate compounds as potential agonists for FFAR4. Molecular structures were encoded into bit arrays, serving as molecular fingerprints, which were subsequently analyzed using the Bayesian network algorithm to identify patterns for screening the data. The shortlisted hits obtained via machine learning protocols …