Amino Acids, Peptides, and Proteins Commons^™

Microgel Core/Shell Architectures As Targeted Agents For Fibrinolysis, Purva Kodlekere, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We demonstrate the utility of microgel core/shell structures conjugated to fibrin-specific peptides as fibrinolytic agents. Poly(N-isopropylmethacrylamide) (pNIPMAm) based microgels conjugated to the peptide GPRPFPAC (GPRP) were observed to bring about fibrin clot erosion, merely through exploitation of the dynamic nature of the clots. These results suggest the potential utility of peptide–microgel hybrids in clot disruption and clotting modulation.

Codon Usage Revisited: Lack Of Correlation Between Codon Usage And The Number Of Trna Genes In Enterobacteria, Joaquín Rojas, Gabriel Castillo, Lorenzo Eugenio Leiva, Sara Elgamal, Omar Orellana, Michael Ibba, Assaf Katz

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

It is widely believed that if a high number of genes are found for any tRNA in a rapidly replicating bacteria, then the cytoplasmic levels of that tRNA will be high and an open reading frame containing a higher frequency of the complementary codon will be translated faster. This idea is based on correlations between the number of tRNA genes, tRNA concentration and the frequency of codon usage observed in a limited number of strains as well as from the fact that artificially changing the number of tRNA genes alters translation efficiency and consequently the amount of properly folded protein …

Visualizing Mutation-Specific Differences In The Trafficking-Deficient Phenotype Of Kv11.1 Proteins Linked To Long Qt Syndrome Type 2, Allison R. Hall, Corey L. Anderson, Jennifer L. Smith, Tooraj Mirshahi, Samy-Claude Elayi, Craig T. January, Brian P. Delisle

Physiology Faculty Publications

KCNH2 encodes the Kv11.1 α-subunit that underlies the rapidly activating delayed-rectifier K⁺ current in the heart. Loss-of-function KCNH2 mutations cause long QT syndrome type 2 (LQT2), and most LQT2-linked missense mutations inhibit the trafficking of Kv11.1 channel protein to the cell surface membrane. Several trafficking-deficient LQT2 mutations (e.g., G601S) generate Kv11.1 proteins that are sequestered in a microtubule-dependent quality control (QC) compartment in the transitional endoplasmic reticulum (ER). We tested the hypothesis that the QC mechanisms that regulate LQT2-linked Kv11.1 protein trafficking are mutation-specific. Confocal imaging analyses of HEK293 cells stably expressing the trafficking-deficient LQT2 mutation F805C showed that, …

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 …

Morphoregulatory Functions Of The Rna-Binding Motif Protein 3 In Cell Spreading, Polarity And Migration, J. Pilotte, W. Kiosses, S. W. Chan, H. P. Makarenkova, Esther E. Dupont-Versteegden, P. W. Vanderklish

Physical Therapy Faculty Publications

RNA-binding proteins are emerging as key regulators of transitions in cell morphology. The RNA-binding motif protein 3 (RBM3) is a cold-inducible RNA-binding protein with broadly relevant roles in cellular protection, and putative functions in cancer and development. Several findings suggest that RBM3 has morphoregulatory functions germane to its roles in these contexts. For example, RBM3 helps maintain the morphological integrity of cell protrusions during cell stress and disease. Moreover, it is highly expressed in migrating neurons of the developing brain and in cancer invadopodia, suggesting roles in migration. We here show that RBM3 regulates cell polarity, spreading and migration. RBM3 …

Development Of Novel Dual Inhibitor Of Chemokine Receptor 4 And Mcl-1 Against Multiple Myeloma, Kuntal Bhowmick, Kristy K. Patel, Suman Pathi, Subash Jonnalagadda, Tulin Budak-Alpdogan, Manoj K. Pandey

Rowan-Virtua Research Day

Multiple myeloma (MM) is a neoplastic plasma-cell disorder. This is characterized by clonal proliferation of malignant plasma cells in the bone-marrow (BM) microenvironment, monoclonal protein in blood or urine, and associated organ dysfunction. The treatment options approved by FDA are immune-modulatory agents, proteasome inhibitors, and autologous stem cell transplantation (ASCT). Unfortunately, MM remains uniformly fatal owing to intrinsic or acquired drug resistance and the median survival time is 3 to 5 years. Thus, there is a great need for novel strategies to combat MM.

The intimate relationship of myeloma cells to BM microenvironment is “hallmark of myeloma”. The homing of …

Matrix Metalloproteinase-Mediated Blood-Brain Barrier Dysfunction In Epilepsy, Ralf G. Rempe, Anika M. S. Hartz, Emma L. B. Soldner, Brent S. Sokola, Satya R. Alluri, Erin L. Abner, Richard J. Kryscio, Anton Pekcec, Juli Schlichtiger, Björn Bauer

Pharmaceutical Sciences Faculty Publications

The blood-brain barrier is dysfunctional in epilepsy, thereby contributing to seizure genesis and resistance to antiseizure drugs. Previously, several groups reported that seizures increase brain glutamate levels, which leads to barrier dysfunction. One critical component of barrier dysfunction is brain capillary leakage. Based on our preliminary data, we hypothesized that glutamate released during seizures mediates an increase in matrix-metalloproteinase (MMP) expression and activity levels, thereby contributing to barrier leakage. To test this hypothesis, we exposed isolated brain capillaries from male Sprague Dawley rats to glutamate ex vivo and used an in vivo/ex vivo approach of isolated brain capillaries …

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 …

The Regulation Of Dna Methylation In Mammalian Development And Cancer, Nicolas Veland

Dissertations and Theses (Open Access)

DNA methylation is an essential epigenetic modification in mammals, as it plays important regulatory roles in multiple biological processes, such as gene transcription, maintenance of chromosomal structure and genomic stability, genomic imprinting, retrotransposon silencing, and X-chromosome inactivation. Dysregulation of DNA methylation is associated with various human diseases. For example, cancer cells usually show global hypomethylation and regional hypermenthylation, which have been implicated in genomic instability and tumor suppressor silencing, respectively. Although great progress has been made in elucidating the biological functions of DNA methylation over the last several decades, how DNA methylation patterns and levels are regulated and dysregulated is …

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 responses, cell death …

Role Of Protein Charge Density On Hepatitis B Virus Capsid Formation, Xinyu Sun, Dong Li, Zhaoshuai Wang, Panchao Yin, Rundong Hu, Rundong Hu, Hui Li, Qiao Liu, Yunyi Gao, Baiping Ren, Jie Zheng, Yinan Wei, Tianbo Liu

Chemistry Faculty Publications

The role of electrostatic interactions in the viral capsid assembly process was studied by comparing the assembly process of a truncated hepatitis B virus capsid protein Cp149 with its mutant protein D2N/D4N, which has the same conformational structure but four fewer charges per dimer. The capsid protein self-assembly was investigated under a wide range of protein surface charge densities by changing the protein concentration, buffer pH, and solution ionic strength. Lowering the protein charge density favored the capsid formation. However, lowering charge beyond a certain point resulted in capsid aggregation and precipitation. Interestingly, both the wild-type and D2N/D4N mutant displayed …

Transmembrane Domains Of Highly Pathogenic Viral Fusion Proteins Exhibit Trimeric Association In Vitro, Stacy R. Webb, Stacy E. Smith, Michael G. Fried, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Enveloped viruses require viral fusion proteins to promote fusion of the viral envelope with a target cell membrane. To drive fusion, these proteins undergo large conformational changes that must occur at the right place and at the right time. Understanding the elements which control the stability of the prefusion state and the initiation of conformational changes is key to understanding the function of these important proteins. The construction of mutations in the fusion protein transmembrane domains (TMDs) or the replacement of these domains with lipid anchors has implicated the TMD in the fusion process. However, the structural and molecular details …

Ef-P Post-Translational Modification Has Variable Impact On Polyproline Translation In Bacillus Subtilis, Anne Witzky, Katherine R. Hummels, Rodney Tollerson Ii, Andrei Rajkovic, Lisa A. Jones, Daniel B. Kearns, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is a ubiquitous translation factor that facilitates translation of polyproline motifs. In order to perform this function, EF-P generally requires posttranslational modification (PTM) on a conserved residue. Although the position of the modification is highly conserved, the structure can vary widely between organisms. In Bacillus subtilis, EF-P is modified at Lys³² with a 5-aminopentanol moiety. Here, we use a forward genetic screen to identify genes involved in 5-aminopentanolylation. Tandem mass spectrometry analysis of the PTM mutant strains indicated that ynbB, gsaB, and ymfI are required for modification and that yaaO, yfkA, and …

Organocatalyzed Synthesis Of Epoxides From Chalcones Utilizing Amino Acids, Sabrina N. Kegeler

Masters Theses

The epoxide functional group is important throughout the chemical and pharmaceutical industries, as well as in nature. In the chemical industry, epoxides are present in resins and fragrances. In the pharmaceutical industry, epoxide-containing compounds are used as intermediates in the manufacturing of drugs. In nature, many natural products contain epoxide groups and are used for medicinal purposes, and for models to create synthetic molecules.

One approach to epoxide synthesis involves the use of an alkene precursor, a base, and an oxidizing agent. This is where my investigations began. The first step was to optimize the epoxidation reaction, examining substrate scope, …

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

UNO 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 …

A Lin28b Tumor-Specific Transcript In Cancer, Weijie Guo, Zhixiang Hu, Yichao Bao, Yuchen Li, Shengli Li, Qiupeng Zheng, Dongbin Lyu, Di Chen, Tao Yu, Yan Li, Xiaodong Zhu, Jie Ding, Yingjun Zhao, Xianghuo He, Shenglin Huang

Markey Cancer Center Faculty Publications

The diversity and complexity of the cancer transcriptome may contain transcripts unique to the tumor environment. Here, we report a LIN28B variant, LIN28B-TST, which is specifically expressed in hepatocellular carcinoma (HCC) and many other cancer types. Expression of LIN28B-TST is associated with significantly poor prognosis in HCC patients. LIN28B-TST initiates from a de novo alternative transcription initiation site that harbors a strong promoter regulated by NFYA but not c-Myc. Demethylation of the LIN28B-TST promoter might be a prerequisite for its transcription and transcriptional regulation. LIN28B-TST encodes a protein isoform with additional N-terminal amino acids and is critical for cancer …

Synthesis, Characterization, And In Vitro Cytotoxicity Of Fatty Acyl-Cgkrk-Chitosan Oligosaccharides Conjugates For Sirna Delivery, Naglaa Salem El-Sayed, Meenakshi Sharma, Hamidreza Montazeri Aliabadi, Magda Goda El-Meligy, Ahmed Kamed El-Zaity, Zenat Adeeb Nageib, Rakesh Tiwari

Pharmacy Faculty Articles and Research

In this studies, three fatty acyl derivatives of CGKRK homing peptides were coupled successfully to chitosan oligosaccharides (COS) using sulfosuccinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate sodium salt (sulfo-SMCC). The COS-SMCC was prepared by direct coupling between COS and sulfo-SMCC in PBS (pH 7.5) at RT for 48 h. The structure of COS-SMCC and the three fatty acyl-CGKRK-SMCC-COS conjugates were characterized by FT-IR, ¹³C NMR, and SEM. The ability of three conjugates to condense siRNA into nanosized polyplexes and their efficacy in protecting siRNA from serum nucleases degradation were investigated. Among the investigated derivatives, S-CGKRK-COS showed higher siRNA binding affinity as compared to …

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

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 studies. …

Neurotensin Receptor 3/Sortilin Contributes To Tumorigenesis Of Neuroendocrine Tumors Through Augmentation Of Cell Adhesion And Migration, Ji Tae Kim, Dana L. Napier, Heidi L. Weiss, Eun Y. Lee, Courtney M. Townsend, B. Mark Evers

Markey Cancer Center Faculty Publications

Neurotensin (NTS), a 13–amino acid peptide which is distributed predominantly along gastrointestinal tract, has multiple physiologic and pathologic functions, and its effects are mediated by three distinct NTS receptors (NTSRs). Overexpression and activation of NTS signaling components, especially NTS and/or NTSR1, are closely linked with cancer progression and metastasis in various types of cancers including neuroendocrine tumors (NETs). Although deregulation of NTSR3/sortilin has been implicated in a variety of human diseases, the expression and role of NTSR3/sortilin in NETs have not been elucidated. In this study, we investigated the expression and oncogenic effect of NTSR3/sortilin in NETs. Increased protein levels …