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Amino Acids, Peptides, and Proteins Commons

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Site-Selective Modification Of Peptides And Proteins Via Organocatalyzed Henry Reaction, Zilma Pereira Muneeswaran 2018 Seton Hall University

Site-Selective Modification Of Peptides And Proteins Via Organocatalyzed Henry Reaction, Zilma Pereira Muneeswaran

Seton Hall University Dissertations and Theses (ETDs)

In this research, peptides and protein containing serine on the N-terminus underwent site-selective modification following organocatalyzed bioconjugation that offered an additional functional group. It was shown that transforming the N-terminus serine to an aldehyde allowed site-specific bioconjugation to occur by utilizing the well-known Henry reaction. This method also grants a safer pathway for bioconjugation utilizing “green-chemistry” and biocompatible conditions. Amino acids and amino acid derived organocatalysts were utilized in the Henry reaction resulting in yields of up to 86 % conversion. Promising preliminary results were achieved in this research using peptides and myoglobin as the bioconjugation targets. Further investigation to be ...


Dissecting Structure-Encoded Determinants Of Allosteric Cross-Talk Between Post-Translational Modification Sites In The Hsp90 Chaperones, Gabrielle Stetz, Amanda Tse, Gennady M. Verkhivker 2018 Chapman University

Dissecting Structure-Encoded Determinants Of Allosteric Cross-Talk Between Post-Translational Modification Sites In The Hsp90 Chaperones, Gabrielle Stetz, Amanda Tse, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Post-translational modifications (PTMs) represent an important regulatory instrument that modulates structure, dynamics and function of proteins. The large number of PTM sites in the Hsp90 proteins that are scattered throughout different domains indicated that synchronization of multiple PTMs through a combinatorial code can be invoked as an important mechanism to orchestrate diverse chaperone functions and recognize multiple client proteins. In this study, we have combined structural and coevolutionary analysis with molecular simulations and perturbation response scanning analysis of the Hsp90 structures to characterize functional role of PTM sites in allosteric regulation. The results reveal a small group of conserved PTMs ...


Linear Ubiquitin Chain-Binding Domains, Lilian Fennell, Simin Rahighi, Fumiyo Ikeda 2018 Vienna BioCenter

Linear Ubiquitin Chain-Binding Domains, Lilian Fennell, Simin Rahighi, Fumiyo Ikeda

Pharmacy Faculty Articles and Research

Ubiquitin modification (ubiquitination) of target proteins can vary with respect to chain lengths, linkage type, and chain forms, such as homologous, mixed, and branched ubiquitin chains. Thus, ubiquitination can generate multiple unique surfaces on a target protein substrate. Ubiquitin‐binding domains (UBDs) recognize ubiquitinated substrates, by specifically binding to these unique surfaces, modulate the formation of cellular signaling complexes and regulate downstream signaling cascades. Among the eight different homotypic chain types, Met1‐linked (also termed linear) chains are the only chains in which linkage occurs on a non‐Lys residue of ubiquitin. Linear ubiquitin chains have been implicated in immune ...


Studies Of Amino Acid Mutations In Drug Resistance Of The Smo Protein, Eunice Wintona 2018 University of Nebraska at Omaha

Studies Of Amino Acid Mutations In Drug Resistance Of The Smo Protein, Eunice Wintona

Student Research and Creative Activity Fair

Smoothened receptor (SMO) is a protein that in humans, is encoded by the SMO gene. A systemic mutation in its binding pocket helps predict the sensitivity of mutant proteins to different drugs. Known as a GPCR-like receptor, it is a component of the hedgehog signaling pathway; a pathway involved in body patterning and the regulation of adult stem cells. An uncontrolled or inappropriate activation of the Hedgehog pathway drives tumor progression in cancers and a number of birth defects. To achieve these goals, the molecular modeling software MOE was used to build small molecules and drug molecules like Vismodegib and ...


Cbx7 Regulates Stem Cell-Like Properties Of Gastric Cancer Cells Via P16 And Akt-Nf-Κb-Mir-21 Pathways., Su-Jie Ni, Li-Qin Zhao, Xiao-Feng Wang, Zhen-Hua Wu, Rui-Xi Hua, Chun-Hua Wan, Jie-Yun Zhang, Xiao-Wei Zhang, Ming-Zhu Huang, Lu Gan, Hua-Lin Sun, Goberdhan P Dimri, Wei-Jian Guo 2018 George Washington University

Cbx7 Regulates Stem Cell-Like Properties Of Gastric Cancer Cells Via P16 And Akt-Nf-Κb-Mir-21 Pathways., Su-Jie Ni, Li-Qin Zhao, Xiao-Feng Wang, Zhen-Hua Wu, Rui-Xi Hua, Chun-Hua Wan, Jie-Yun Zhang, Xiao-Wei Zhang, Ming-Zhu Huang, Lu Gan, Hua-Lin Sun, Goberdhan P Dimri, Wei-Jian Guo

Biochemistry and Molecular Medicine Faculty Publications

BACKGROUND: Chromobox protein homolog 7 (CBX7), a member of the polycomb group (PcG) family of proteins, is involved in the regulation of cell proliferation and cancer progression. PcG family members, such as BMI, Mel-18, and EZH2, are integral constituents of the polycomb repressive complexes (PRCs) and have been known to regulate cancer stem cell (CSC) phenotype. However, the role of other PRCs' constituents such as CBX7 in the regulation of CSC phenotype remains largely elusive. This study was to investigate the role of CBX7 in regulating stem cell-like properties of gastric cancer and the underlying mechanisms.

METHODS: Firstly, the role ...


Simian Virus 40 Large T Antigen As A Model To Test The Efficacy Of Flouroquinolones Against Viral Helicases, Sammer Siddiqui, Muhammad F. Anwar, Sadaf Naeem, Syed Hani Abidi, Shamshad Zarina, Syed Ali 2018 Tulane University, New Orleans, LA, USA

Simian Virus 40 Large T Antigen As A Model To Test The Efficacy Of Flouroquinolones Against Viral Helicases, Sammer Siddiqui, Muhammad F. Anwar, Sadaf Naeem, Syed Hani Abidi, Shamshad Zarina, Syed Ali

Department of Biological & Biomedical Sciences

Simian virus 40 large T-antigen (SV40 LT-Ag) is a 708 amino acid nuclear phosphoprotein. Among many functions of LT-Ag is its ability to perform as an ATPase-helicase, catalyzing the unwinding of viral genome during replication. The LT-Ag has been employed in the studies of helicase structure and function, and has served as a model helicase for the screening of antiviral drugs that target viral helicase. In this study, using in vitro enzyme assays and in silico computer modeling, we screened a batch of 18 fluoroquinolones to assess their potential as antivirals by virtue of their inhibition of the LT-Ag helicase ...


Novel Combination Bmp7 And Hgf Gene Therapy Instigates Selective Myofibroblast Apoptosis And Reduces Corneal Haze In Vivo, Suneel Gupta, Michael K. Fink, Arkasubhra Ghosh, Ratnakar Tripathi, Prashant R. Sinha, Ajay Sharma, Nathan P. Hesemann, Shyam S. Chaurasia, Elizabeth A. Giuliano, Rajiv R. Mohan 2018 Harry S. Truman Memorial Veterans’ Hospital

Novel Combination Bmp7 And Hgf Gene Therapy Instigates Selective Myofibroblast Apoptosis And Reduces Corneal Haze In Vivo, Suneel Gupta, Michael K. Fink, Arkasubhra Ghosh, Ratnakar Tripathi, Prashant R. Sinha, Ajay Sharma, Nathan P. Hesemann, Shyam S. Chaurasia, Elizabeth A. Giuliano, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

PURPOSE. We tested the potential of bone morphogenic protein 7 (BMP7) and hepatocyte growth factor (HGF) combination gene therapy to treat preformed corneal fibrosis using established rabbit in vivo and human in vitro models.

METHODS. Eighteen New Zealand White rabbits were used. Corneal fibrosis was produced by alkali injury. Twenty-four hours after scar formation, cornea received topically either balanced salt solution (BSS; n ¼ 6), polyethylenimine-conjugated gold nanoparticle (PEI2-GNP)-naked plasmid (n ¼ 6) or PEI2-GNP plasmids expressing BMP7 and HGF genes (n ¼ 6). Donor human corneas were used to obtain primary human corneal fibroblasts and myofibroblasts for mechanistic ...


Functionalizing Titanium Implants With Bioactive Peptides To Increase Osseointegration, Neil Bernard 2018 The University of Akron

Functionalizing Titanium Implants With Bioactive Peptides To Increase Osseointegration, Neil Bernard

Honors Research Projects

Orthopedic surgeries have continued to increase, but the material of choice remains constant: titanium. Titanium has become the benchmark implant material due to its durability and non-immunogenic properties. However, while high rates of success are correlated with joint replacement surgery, certain patients with predisposed diseases such as diabetes or arthritis may have increased complications.1 This can be due to lack of osseointegration due to decreased bone formation and mineralization,2 which will lead to increased rates of infection or aseptic loosening of the implant from the bone. 3 Current methods to alleviate these complications include invasive revisional surgeries, which ...


Thermophilic Adaptation In Prokaryotes Is Constrained By Metabolic Costs Of Proteostasis, Sergey V. Venev, Konstantin B. Zeldovich 2018 University of Massachusetts Medical School

Thermophilic Adaptation In Prokaryotes Is Constrained By Metabolic Costs Of Proteostasis, Sergey V. Venev, Konstantin B. Zeldovich

Open Access Articles

Prokaryotes evolved to thrive in an extremely diverse set of habitats, and their proteomes bear signatures of environmental conditions. Although correlations between amino acid usage and environmental temperature are well-documented, understanding of the mechanisms of thermal adaptation remains incomplete. Here, we couple the energetic costs of protein folding and protein homeostasis to build a microscopic model explaining both the overall amino acid composition and its temperature trends. Low biosynthesis costs lead to low diversity of physical interactions between amino acid residues, which in turn makes proteins less stable and drives up chaperone activity to maintain appropriate levels of folded, functional ...


Sptransformer Proteins From The Purple Sea Urchin Opsonize Bacteria, Augment Phagocytosis, And Retard Bacterial Growth, H. Y. Chou, C. Lun, L. C. Smith 2018 George Washington University

Sptransformer Proteins From The Purple Sea Urchin Opsonize Bacteria, Augment Phagocytosis, And Retard Bacterial Growth, H. Y. Chou, C. Lun, L. C. Smith

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The purple sea urchin, Strongylocentrotus purpuratus, has a complex and robust immune system that is mediated by a number of multi-gene families including the SpTransformer (SpTrf) gene family (formerly Sp185/333). In response to immune challenge from bacteria and various pathogen-associated molecular patterns, the SpTrf genes are up-regulated in sea urchin phagocytes and express a diverse array of SpTrf proteins. We show here that SpTrf proteins from coelomocytes and isolated by nickel affinity (cNi-SpTrf) bind to Gram-positive and Gram-negative bacteria and to Baker’s yeast, Saccharomyces cerevisiae, with saturable kinetics and specificity. cNi-SpTrf opsonization of the marine bacteria, Vibrio diazotrophicus ...


Structural Insights Into The Potency Of Sk Channel Positive Modulators, Young-Woo Nam, Razan Orfali, Tingting Liu, Kunqian Yu, Meng Cui, Heike Wulff, Miao Zhang 2017 Chapman University

Structural Insights Into The Potency Of Sk Channel Positive Modulators, Young-Woo Nam, Razan Orfali, Tingting Liu, Kunqian Yu, Meng Cui, Heike Wulff, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca2+-activated K+ (SK) channels play essential roles in the regulation of cellular excitability and have been implicated in neurological and cardiovascular diseases through both animal model studies and human genetic association studies. Over the past two decades, positive modulators of SK channels such as NS309 and 1-EBIO have been developed. Our previous structural studies have identified the binding pocket of 1-EBIO and NS309 that is located at the interface between the channel and calmodulin. In this study, we took advantage of four compounds with potencies varying over three orders of magnitude, including 1-EBIO, NS309, SKS-11 (6-bromo-5-methyl-1H-indole-2 ...


Genetic Signatures For Helicobacter Pylori Strains Of West African Origin, Kennady K. Bullock, Carrie L. Shaffer, Andrew W. Brooks, Ousman Secka, Mark H. Forsyth, Mark S. McClain, Timothy L. Cover 2017 Vanderbilt University

Genetic Signatures For Helicobacter Pylori Strains Of West African Origin, Kennady K. Bullock, Carrie L. Shaffer, Andrew W. Brooks, Ousman Secka, Mark H. Forsyth, Mark S. Mcclain, Timothy L. Cover

Veterinary Science Faculty Publications

Helicobacter pylori is a genetically diverse bacterial species that colonizes the stomach in about half of the human population. Most persons colonized by H. pylori remain asymptomatic, but the presence of this organism is a risk factor for gastric cancer. Multiple populations and subpopulations of H. pylori with distinct geographic distributions are recognized. Genetic differences among these populations might be a factor underlying geographic variation in gastric cancer incidence. Relatively little is known about the genomic features of African H. pylori strains compared to other populations of strains. In this study, we first analyzed the genomes of H. pylori strains ...


Protocol For Analyzing Protein Ensemble Structures From Chemical Cross-Links Using Dynaxl, Zhou Gong, Zhu Liu, Xu Dong, Yue-He Ding, Meng-Qiu Dong, Chun Tang 2017 Wuhan Institute of Physics and Mathematics of the Chinese Academy of Sciences

Protocol For Analyzing Protein Ensemble Structures From Chemical Cross-Links Using Dynaxl, Zhou Gong, Zhu Liu, Xu Dong, Yue-He Ding, Meng-Qiu Dong, Chun Tang

Open Access Articles

Chemical cross-linking coupled with mass spectroscopy (CXMS) is a powerful technique for investigating protein structures. CXMS has been mostly used to characterize the predominant structure for a protein, whereas cross-links incompatible with a unique structure of a protein or a protein complex are often discarded. We have recently shown that the so-called over-length cross-links actually contain protein dynamics information. We have thus established a method called DynaXL, which allow us to extract the information from the over-length cross-links and to visualize protein ensemble structures. In this protocol, we present the detailed procedure for using DynaXL, which comprises five steps. They ...


Ensemble-Based Modeling And Rigidity Decomposition Of Allosteric Interaction Networks And Communication Pathways In Cyclin-Dependent Kinases: Differentiating Kinase Clients Of The Hsp90-Cdc37 Chaperone, Gabrielle Stetz, Amanda Tse, Gennady M. Verkhivker 2017 Chapman University

Ensemble-Based Modeling And Rigidity Decomposition Of Allosteric Interaction Networks And Communication Pathways In Cyclin-Dependent Kinases: Differentiating Kinase Clients Of The Hsp90-Cdc37 Chaperone, Gabrielle Stetz, Amanda Tse, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

The overarching goal of delineating molecular principles underlying differentiation of protein kinase clients and chaperone-based modulation of kinase activity is fundamental to understanding activity of many oncogenic kinases that require chaperoning of Hsp70 and Hsp90 systems to attain a functionally competent active form. Despite structural similarities and common activation mechanisms shared by cyclin-dependent kinase (CDK) proteins, members of this family can exhibit vastly different chaperone preferences. The molecular determinants underlying chaperone dependencies of protein kinases are not fully understood as structurally similar kinases may often elicit distinct regulatory responses to the chaperone. The regulatory divergences observed for members of CDK ...


Difatty Acyl-Conjugated Linear And Cyclic Peptides For Sirna Delivery, Hung Do, Meenakshi Sharma, Naglaa Salem El-Sayed, Parvin Mahdipoor, Emira Bousoik, Keykavous Parang, Hamidreza Montazeri Aliabadi 2017 Chapman University

Difatty Acyl-Conjugated Linear And Cyclic Peptides For Sirna Delivery, Hung Do, Meenakshi Sharma, Naglaa Salem El-Sayed, Parvin Mahdipoor, Emira Bousoik, Keykavous Parang, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

A number of amphiphilic difatty acyl linear and cyclic R5K2 peptide conjugates were synthesized by solid-phase peptide methods to enhance the interaction with the hydrophobic cellular phospholipid bilayer and to improve siRNA delivery and silencing. Binding to siRNA molecules was significantly less for the cyclic peptide conjugates. A gradual decrease was observed in the particle size of the complexes with increasing peptide/siRNA ratio for most of the synthesized peptides, suggesting the complex formation. Most of the complexes showed a particle size of less than 200 nm, which is considered an appropriate size for in vitro siRNA delivery. A number ...


Role Of Microglial Amylin Receptors In Mediating Beta Amyloid (Aβ)-Induced Inflammation, Wen Fu, Vlatka Vukojevic, Aarti Patel, Rania Soudy, David MacTavish, David Westaway, Kamaljit Kaur, Valeri Goncharuk, Jack Jhamandas 2017 University of Alberta

Role Of Microglial Amylin Receptors In Mediating Beta Amyloid (Aβ)-Induced Inflammation, Wen Fu, Vlatka Vukojevic, Aarti Patel, Rania Soudy, David Mactavish, David Westaway, Kamaljit Kaur, Valeri Goncharuk, Jack Jhamandas

Pharmacy Faculty Articles and Research

Background: Neuroinflammation in the brain consequent to activation of microglia is viewed as an important component of Alzheimer’s disease (AD) pathology. Amyloid beta (Aβ) protein is known to activate microglia and unleash an inflammatory cascade that eventually results in neuronal dysfunction and death. In this study, we sought to identify the presence of amylin receptors on human fetal and murine microglia and determine whether Aβ activation of the inflammasome complex and subsequent release of cytokines is mediated through these receptors.

Methods: The presence of dimeric components of the amylin receptor (calcitonin receptor and receptor activity modifying protein 3) were ...


Hmgb1 Redox During Sepsis, Wasan Abdulmahdi, Devika Patel, May Rabadi, Tala Azar, Edson Jules, Mark Lipphardt, Rameen Hashemiyoon, Brian B. Ratliff 2017 New York Medical College

Hmgb1 Redox During Sepsis, Wasan Abdulmahdi, Devika Patel, May Rabadi, Tala Azar, Edson Jules, Mark Lipphardt, Rameen Hashemiyoon, Brian B. Ratliff

NYMC Faculty Publications

During sepsis, the alarmin HMGB1 is released from tissues and promotes systemic inflammation that results in multi-organ damage, with the kidney particularly susceptible to injury. The severity of inflammation and pro-damage signaling mediated by HMGB1 appears to be dependent on the alarmin's redox state. Therefore, we examined HMGB1 redox in kidney cells during sepsis. Using intravital microscopy, CellROX labeling of kidneys in live mice indicated increased ROS generation in the kidney perivascular endothelium and tubules during lipopolysaccharide (LPS)-induced sepsis. Subsequent CellROX and MitoSOX labeling of LPS-stressed endothelial and kidney proximal tubule cells demonstrated increased ROS generation in these ...


Age Drives Distortion Of Brain Metabolic, Vascular And Cognitive Functions, And The Gut Microbiome, Jared D. Hoffman, Ishita Parikh, Stefan J. Green, George Chlipala, Robert P. Mohney, Mignon Keaton, Bjoern Bauer, Anika M. S. Hartz, Ai-Ling Lin 2017 University of Kentucky

Age Drives Distortion Of Brain Metabolic, Vascular And Cognitive Functions, And The Gut Microbiome, Jared D. Hoffman, Ishita Parikh, Stefan J. Green, George Chlipala, Robert P. Mohney, Mignon Keaton, Bjoern Bauer, Anika M. S. Hartz, Ai-Ling Lin

Sanders-Brown Center on Aging Faculty Publications

Advancing age is the top risk factor for the development of neurodegenerative disorders, including Alzheimer’s disease (AD). However, the contribution of aging processes to AD etiology remains unclear. Emerging evidence shows that reduced brain metabolic and vascular functions occur decades before the onset of cognitive impairments, and these reductions are highly associated with low-grade, chronic inflammation developed in the brain over time. Interestingly, recent findings suggest that the gut microbiota may also play a critical role in modulating immune responses in the brain via the brain-gut axis. In this study, our goal was to identify associations between deleterious changes ...


Suppression Of Chrn Endocytosis By Carbonic Anhydrase Car3 In The Pathogenesis Of Myasthenia Gravis, Ailian Du, Shiqian Huang, Xiaonan Zhao, Kuan Fang, Shuangyan Zhang, Jiefang Huang, Xiang Miao, Fulvio Baggi, Rennolds S. Ostrom, Yanyun Zhang, Xiangjun Chen, Congfeng Xu 2017 Shanghai Jiao Tong University

Suppression Of Chrn Endocytosis By Carbonic Anhydrase Car3 In The Pathogenesis Of Myasthenia Gravis, Ailian Du, Shiqian Huang, Xiaonan Zhao, Kuan Fang, Shuangyan Zhang, Jiefang Huang, Xiang Miao, Fulvio Baggi, Rennolds S. Ostrom, Yanyun Zhang, Xiangjun Chen, Congfeng Xu

Pharmacy Faculty Articles and Research

Myasthenia gravis is an autoimmune disorder of the neuromuscular junction manifested as fatigable muscle weakness, which is typically caused by pathogenic autoantibodies against postsynaptic CHRN/ AChR (cholinergic receptor nicotinic) in the endplate of skeletal muscle. Our previous studies have identified CA3 (carbonic anhydrase 3) as a specific protein insufficient in skeletal muscle from myasthenia gravis patients. In this study, we investigated the underlying mechanism of how CA3 insufficiency might contribute to myasthenia gravis. Using an experimental autoimmune myasthenia gravis animal model and the skeletal muscle cell C2C12, we find that inhibition of CAR3 (the mouse homolog of CA3) promotes CHRN ...


Heightened Circulating Levels Of Antimicrobial Peptides In Tuberculosis-Diabetes Co-Morbidity And Reversal Upon Treatment, Nathella Pavan Kumar, Kadar Moideen, Vijay Viswanathan, Shanmugam Sivakumar, Pradeep A. Menon, Hardy Kornfeld, Subash Babu 2017 National Institutes of Health-NIRT-International Center for Excellence in Research

Heightened Circulating Levels Of Antimicrobial Peptides In Tuberculosis-Diabetes Co-Morbidity And Reversal Upon Treatment, Nathella Pavan Kumar, Kadar Moideen, Vijay Viswanathan, Shanmugam Sivakumar, Pradeep A. Menon, Hardy Kornfeld, Subash Babu

Open Access Articles

BACKGROUND: The association of antimicrobial peptides (AMPs) with tuberculosis-diabetes comorbidity (PTB-DM) is not well understood.

METHODS: To study the association of AMPs with PTB-DM, we examined the systemic levels of cathelicidin (LL37), human beta defensin- 2 (HBD2), human neutrophil peptides 1-3, (HNP1-3) and granulysin in individuals with either PTB-DM, PTB, latent TB (LTB) or no TB infection (NTB).

RESULTS: Circulating levels of cathelicidin and HBD2 were significantly higher and granulysin levels were significantly lower in PTB-DM compared to PTB, LTB or NTB, while the levels of HNP1-3 were significantly higher in PTB-DM compared to LTB or NTB individuals. Moreover, the ...


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