Amino Acids, Peptides, and Proteins Commons^™

Deciphering The Chemistry Of Condensed Aromatic "Black" Carbon And Nitrogen In Amazonian Anthrosols, João Vitor Dos Santos, Aleksandar I. Goranov, Laís G. Fregolente, Marcia C. Bisinoti, Zhenhuan Sun, Klaus Schmidt-Rohr, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Amazonian anthrosols are renowned for their high fertility and dark color, properties primarily attributed to the abundance of condensed aromatic carbon (ConAC) in the soil organic matter. ConAC, commonly referred to as black carbon, play a key role in the stability and nutrient retention of these soils. However, the processes governing the formation of ConAC and its transformation into oxygenated derivatives remain poorly understood. In this study, we used multiple analytical platforms to investigate the chemistry of ConAC-rich humic acids (HA) extracted from Terra Mulata de Indio, a type of Amazonian anthrosol. The results reveal that ConAC are predominantly …

Neurotensin Regulates Primate Ovulation Via Multiple Neurotensin Receptors, Andrew C. Pearson, Jessica S. Miller, Hannah J. Jensen, Ketan Shrestha, Thomas E. Curry Jr., Diane M. Duffy

Department of Biomedical and Translational Sciences Faculty Publications

Neurotensin (NTS), a small neuropeptide, was recently established as a key paracrine mediator of ovulation. NTS mRNA is highly expressed by granulosa cells in response to the luteinizing hormone (LH) surge, and multiple NTS receptors are expressed by cells of the ovulatory follicle. To identify the role of NTS receptors NTSR1 and SORT1 in ovulation in vivo, the dominant follicle of cynomolgus macaques (Macaca fascicularis) was injected with either vehicle control, the general NTS receptor antagonist SR142948, the NTSR1-selective antagonist SR48692, or the SORT1-selective antagonist AF38469. Human chorionic gonadotropin (hCG) was then administered to initiate ovulatory events. …

Multimodal Imaging Of Protein-Based Biomaterials For Delivering Chemo-Agent Cargo For Glioblastoma Treatment In A Murine Model, Orin Mishkit

Dissertations and Theses

Protein-based self-assembling biomaterials, known as Thermo-Responsive Assembled Proteins (TRAP), present meaningful potential as drug delivery carriers. These materials enable the controlled, slow release of poorly soluble chemotherapeutic agents, such as doxorubicin (Dox), while potentially reducing systemic off-target effects. In collaboration with multiple NYU labs, this study evaluated the efficacy of two TRAP variants—TRAP and F-TRAP—as drug delivery carriers in a xenograft mouse model of glioblastoma multiforme (GBM).

The primary objective was to compare the effectiveness of TRAP-loaded Dox (TRAP-DOX) to free Dox in achieving tumor extravasation and accumulation, facilitating sustained drug release. We hypothesized that the leaky vasculature of GBM …

Ribosome Hibernation In Mycobacterium Abscessus And Its Effect On Antibiotic Resistance, Ryan Treen

Electronic Theses & Dissertations (2024 - present)

Non-tuberculosis mycobacteria (NTM) represent a diverse repertoire of species, most of which are ubiquitous in the environment. Some NTM species, such as Mycobacterium abscessus, can cause life-threatening infections in people with underlying medical conditions. The clinical incidence of such infections is on the rise, posing an emerging threat to public health. M. abscessus is characterized by intrinsic and acquired antibiotic resistance, complicating treatment strategies. Most chemotherapeutic approaches for M. abscessus infection target the bacterial ribosome, necessitating a better understanding of the physiological processes which confer this resistance. Multiple mycobacterial species respond to zinc-limiting conditions by inducing remodeling and hibernation …

Interaction Of Cardiac Leiomodin With The Native Cardiac Thin Filament, Madison Little, Cristina M. Risi, Tania M. Larrinaga, Mason D. Summers, Tyler Nguyen, Garry E. Smith Jr., Jennifer Atherton, Carol C. Gregorio, Alla S. Kostyukova, Vitold E. Galkin

Department of Biomedical and Translational Sciences Faculty Publications

Every heartbeat depends on cyclical contraction-relaxation produced by the interactions between myosin-containing thick and actin-based thin filaments (TFs) arranged into a crystalline-like lattice in the cardiac sarcomere. Therefore, the maintenance of thin filament length is crucial for myocardium function. The thin filament is comprised of an actin backbone, the regulatory troponin complex and tropomyosin that controls interactions between thick and thin filaments. Thin filament length is controlled by the tropomodulin family of proteins; tropomodulin caps pointed ends of thin filaments, and leiomodin (Lmod) promotes elongation of thin filaments by a “leaky-cap” mechanism. The broader distribution of Lmod on the thin …

Swinging Lever Mechanism Of Myosin Directly Shown By Time-Resolved Cryo-Em, David P. Klebl, Sean N. Mcmillan, Cristina Risi, Eva Forgacs, Betty Virok, Jennifer L. Atherton, Sarah A. Harris, Michele Stofella, Donald A. Winkelmann, Frank Sobott, Vitold E. Galkin, Peter J. Knight, Stephen P. Muench, Charlotte A. Scarfi, Howard D. White

Department of Biomedical and Translational Sciences Faculty Publications

Myosins produce force and movement in cells through interactions with F-actin¹. Generation of movement is thought to arise through actin-catalysed conversion of myosin from an ATP-generated primed (pre-powerstroke) state to a post-powerstroke state, accompanied by myosin lever swing²,³. However, the initial, primed actomyosin state has never been observed, and the mechanism by which actin catalyses myosin ATPase activity is unclear. Here, to address these issues, we performed time-resolved cryogenic electron microscopy (cryo-EM)⁴ of a myosin-5 mutant having slow hydrolysis product release⁵,⁶. Primed actomyosin was predominantly captured 10 ms after …

Deletion Of Chop In Beta Cell Protects Mice From Cardiovascular Complications In Type 2 Diabetes: Evidence From A Pre-Clinical Mouse Model, Balaji Srinivas, Kiran Alluri, Nour-Eddine Rhaleb, Khalid Matrougui

Department of Biomedical and Translational Sciences Faculty Publications

Introduction

Cardiovascular complications are the leading cause of morbidity and mortality in patients with type 2 diabetes (T2D), which is recognized as a major independent risk factor for coronary artery disease, stroke, peripheral vascular disease, and heart failure. The interrelationship between metabolic dysfunction and cardiovascular disease is complex and multifactorial, involving hyperglycemia, insulin resistance, inflammation, and oxidative stress. Evidence indicates that endoplasmic reticulum (ER) stress and induction of the unfolded protein response (UPR) contribute to metabolic dysregulation and vascular dysfunction. However, the specific role of beta cell-derived UPR mediators, particularly C/EBP homologous protein (CHOP), in coordinating this interorgan axis between …

Phenotype Specific Nuclear Lamina Remodeling In Hipsc Derived Cardiomyocytes Bearing Tnnt2 Sarcomeric Variants, Isabella Leite Coscarella, Olalekan H. Usman, Lili Wang, Maicon Landim-Vieira, Lillian Wirstiuk, Amber N. Brown, Diego A. R. Zorio, Brian K. Washburn, Cynthia Vied, Bjorn C. Knollmann, Christopher Solís, Vitold E. Galkin, P. Bryant Chase, J. Travis Hinson, Jerome Irianto, Jose Renato Pinto

Department of Biomedical and Translational Sciences Faculty Publications

[Summary] Cardiomyocytes endure physical stress from the myocardium environment while generating their own mechanical strains. The force generated by sarcomeres is transmitted both longitudinally to adjacent sarcomeres and laterally to the cytoskeleton via intermediate filaments. This mechanical stimulus impacts other organelles, including the nucleus, thus playing a vital role in sensing and signaling nuclear adaptations. However, there is limited understanding of how changes in cardiac contractility affect nuclear mechanics. Here, we sought to investigate the effects of hyper- and hypo-contractility in nuclei of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) bearing TNNT2 pathogenic variants associated with hypertrophic (HCM) or dilated …

Structural Optimization And Stability Enhancement Of Uba(2) And Ntl9 Using The Computational Tool: Emcast, Bahar Ghazi Esfahani

Graduate Student Theses, Dissertations, & Professional Papers

This study enhances protein stability prediction by refining EmCAST (Empirical C-Alpha Stability Tool), a computational tool used to identify stabilizing mutations in protein domains. We applied EmCAST to two model proteins: the α-helical ubiquitin-associated domain 2 (UBA(2)) and the α/β N-terminal domain of ribosomal protein L9 (NTL9). Protein stability is critical for proper function, and mutations can lead to misfolding and disease. To validate EmCAST’s predictions, guanidine hydrochloride-induced denaturation was monitored using circular dichroism (CD) spectroscopy for both wild-type and mutant variants. Results guided refinements to EmCAST’s algorithm, incorporating new experimental datasets to improve accuracy. Additionally, we examined the assumption …

Redox Control In A Fused Electron Transfer Flavoprotein From A Thermophilic Archaeon And Expanded Significance Of A Hydrogen Bond From A Conserved Histidine Residue That Contributes To Flavin Redox Tuning And Activation For Covalent Modification, Debarati Das

Theses and Dissertations--Chemistry

In absence of O₂ as terminal electron acceptors in anaerobic bacteria and archaea, carbohydrate metabolism is 15 times less efficient compared to aerobic energy metabolism resulting in energy deficit conditions. Despite their meager resources these anaerobes were able to generate H₂ and a chemiosmotic potential able to drive energy demanding reactions such as CO₂ or N₂ fixation. These observations raised concerns as production of high energy reductants (H₂) from mediocre fuels (NADH) defied the laws of thermodynamics.

In 2008, a known mechanism “electron bifurcation” but with flavins as redox mediators instead of quinones was …

Determination Of Structural Factors Contributing To Protection Of Zinc Fingers In Estrogen Receptor Α Through Molecular Dynamic Simulations, Patricia B. Lutz, Wesley R. Coombs, Craig A. Bayse

Chemistry & Biochemistry Faculty Publications

The ERα transcription factor that induces tumor growth is a potential target for breast cancer treatment. Each monomer of the ERα DNA-binding domain (ERαDBD) homodimer has two conserved (Cys)₄-type zinc fingers, ZF1 (N-terminal) and ZF2 (C-terminal). Electrophilic agents release Zn²⁺ by oxidizing the coordinating Cys of the more labile ZF2 to inhibit dimerization and DNA binding. Microsecond-length molecular dynamics (MD) simulations show that greater flexibility of ZF2 in the ERαDBD monomer leaves its Cys more solvent accessible and less shielded from electrophilic attack by sulfur-centered hydrogen bonds than ZF1 which is buried in the protein. In the …

A Scoping Review Of Population Diversity In The Common Genomic Aberrations Of Clear Cell Renal Cell Carcinoma, Sean S. Kumar, Ninad Khandekar, Komal Dani, Saina R. Bhatt, Vinay Duddalwar, Anishka D' Souza

Department of Medicine Faculty Publications

Introduction: Previous literature has shown that clear cell renal cell carcinoma (ccRCC) is becoming a more prevalent diagnosis and that the incidence and mortality differ both regionally and racially. While the molecular profiles for ccRCC are studied regionally through biopsy and sequencing techniques, the genomic landscape and ccRCC diversity data are not well studied. We conducted a review of the known genomic data on 6 of the most clinically relevant DNA biomarkers in ccRCC: von Hippel-Lindau (vHL), Polybromo-1 (PBRM1), Breast Cancer Gene 1-Associated Protein 1 (BAP1), Histone-Lysine N-Methyltransferase Domain-Containing 2 (SETD2), Mammalian Target of Rapamycin (mTOR), and Lysine-Specific Demethylase 5C …

Changes In Cardiovascular Risk Factors And Health Care Expenditures Among Patients Prescribed Semaglutide, Yuan Lu, Yuntian Lu, Tedi Totojani, Chungsoo Kim, Rohan Khera, Hua Xu, John E. Brush Jr., Harlan M. Krumholtz, Jason Abaluck

Department of Medicine Faculty Publications

Importance Semaglutide, a glucagon-like peptide-1 receptor agonist, has demonstrated substantial weight reduction and cardiovascular benefits in clinical trials. However, its association with clinical outcomes and health care expenditures remains underexplored.

Objective To evaluate changes in cardiovascular risk factors and health care expenditures among patients prescribed semaglutide across multicenter cohorts.

Design, Setting, and Participants This retrospective cohort study included 23 522 adults (≥18 years) who received an initial semaglutide prescription between January 1, 2018, and January 1, 2025, at Sentara Healthcare and between January 1, 2018, and May 1, 2025, at Yale New Haven Health System.

Exposure The first prescription of …

Her2 Alterations Across Solid Tumors: Implications For Comprehensive Testing, Ahmed Ismail, Chimay Jani, Nusrat Jahan, Malla Midhun, Arnab Basu, Garima Gupta, Bassel El-Rayes, Sejong Bae, Tyler Mattox, Cyntanna Hawkins, Rebecca C. Arend, Mehmet Akce, Yanis Boumber, Aakash Desai

Department of Medicine Faculty Publications

Purpose

ERBB2 (HER2) alterations (e.g., overexpression, amplification, and mutations) are known to drive tumor progression. These changes, particularly in non-breast and gastric/gastroesophageal cancers, remain poorly characterized. With pan-tumor approval of HER2-targeted therapies like Trastuzumab deruxetecan (T-DXd), understanding ERBB2 alterations across diverse cancers is crucial.

Methods

HER2 analysis was conducted on 653 solid tumor specimens at the University of Alabama, using immunohistochemistry (IHC), copy number (CN) variation (CNV) assessment, and mutational profiling. The correlation between CN amplification and IHC expression was evaluated using Somers' D ordinal association.

Results

Of the 653 cases, HER2 IHC scores were distributed as 3 + (3.1%), …

A Novel D-Peptide Modulates Dclk1 Gelsolin Interactions, Reducing Pdac Tumor Growth, Landon L. Moore, Dongfeng Qu, Parthasarathy Chandrekesan, Kamille Pitts, Randal May, Byron E. Anderson, Milton L. Brown, Courtney W. Houchen

Department of Medicine Faculty Publications

What drives inflammation-associated tumorigenesis and progression in pancreatic ductal adenocarcinoma (PDAC)? Doublecortin-like kinase 1 (DCLK1) is a central driver of inflammation-associated tumorigenesis, with elevated expression linked to worse clinical outcomes. Two isoforms of DCLK1 possess a unique extracellular domain (ECD). DCLK1 isoform 2 contains two microtubule-binding domains, while isoform 4, lacks the microtubule-binding domains but, plays a pivotal role in tumor progression. We identified novel D-peptides that selectively target this ECD, significantly suppressing PDAC cell proliferation in vitro and tumor growth in xenograft models without inducing cell death. In silico modeling and binding assays revealed DCLK1 isoform 4 interacts with …

Fibrinolysis For Apical Thrombus As A Bridge To Emergent Valve-In-Valve Transcatheter Aortic Valve Replacement, Nicholas J. Valle, Omar A. Saleh, Mani C. Akunuri, Parth K. Parikh, Joshua A. Cohen, Deepak R. Talreja, Matthew R. Summers

Department of Medicine Faculty Publications

Background

Left ventricular (LV) thrombus is traditionally a contraindication to transcatheter aortic valve replacement due to embolic risk. Consequently, management of valvular cardiogenic shock complicated by LV thrombus identifies unique challenges that require innovative strategies.

Case Summary

A 58-year-old woman with critical bioprosthetic aortic stenosis, cardiogenic shock, and large LV thrombus (2.8 × 2.6 cm) underwent successful valve-in-valve transcatheter aortic valve replacement after systemic fibrinolysis bridge therapy.

Why Beyond the Guidelines

Current guidelines contraindicate transcatheter aortic valve replacement in patients with LV thrombus. This case demonstrates the novel use of low-dose, slow infusion tissue plasminogen activator as a bridge therapy …

Automating The Amino Acid Identification In Elliptical Dichroism Spectrometer With Machine Learning, Ridhanya Sree Balamurugan, Yusuf Asad, Tommy Gao, Dharmakeerthi Nawarathna, Umamaheswara Rao Tida, Dali Sun

Electrical & Computer Engineering Faculty Publications

Amino acid identification is crucial across various scientific disciplines, including biochemistry, pharmaceutical research, and medical diagnostics. However, traditional methods such as mass spectrometry require extensive sample preparation and are time-consuming, complex and costly. Therefore, this study presents a pioneering Machine Learning (ML) approach for automatic amino acid identification by utilizing the unique absorption profiles from an Elliptical Dichroism (ED) spectrometer. Advanced data preprocessing techniques and ML algorithms to learn patterns from the absorption profiles that distinguish different amino acids were investigated to prove the feasibility of this approach. The results show that ML can potentially revolutionize the amino acid analysis …

Reversible Degradation Of Peptidoglycan By Lytic Transglycosylases, Aaron Devereaux

Theses and Dissertations (Comprehensive)

Antimicrobial resistance continues to be a burden on the global healthcare system with an estimated cost of billions of dollars and millions of deaths each year. Recently, there has been little to no development on new antibiotics to treat bacterial infection, and any that are developed become resisted to within a few years. Both Gram-positive and Gram-negative bacteria contain a mesh-like layer called peptidoglycan (PG) that surrounds their cells providing strength, cell shape, and protection from their environments. This layer is a polymer of N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) connected via a b-1,4-glycosidic bond, with each strand being cross-linked …

Cath-Ddg: Towards Robust Mutation Effect Prediction On Protein-Protein Interactions Out Of Cath Homologous Superfamily, Guanglei Yu, Xuehua Bi, Teng Ma, Yaohang Li, Jianxin Wang

Computer Science Faculty Publications

Motivation: Protein-protein interactions (PPIs) are fundamental aspects in understanding biological processes. Accurately predicting the effects of mutations on PPIs remains a critical requirement for drug design and disease mechanistic studies. Recently, deep learning models using protein 3D structures have become predominant for predicting mutation effects. However, significant challenges remain in practical applications, in part due to the considerable disparity in generalization capabilities between easy and hard mutations. Specifically, a hard mutation is defined as one with its maximum TM-score < 0.6 when compared to the training set. Additionally, compared to physics-based approaches, deep learning models may overestimate performance due to potential data leakage.

Results: We propose new training/test splits that mitigate data leakage according to the CATH homologous superfamily. Under the constraints of physical …

A Survey On Deep Learning For Drug-Target Binding Prediction: Models, Benchmarks, Evaluation, And Case Studies, Kusal Debnath, Pratip Rana, Preetam Ghosh

Computer Science Faculty Publications

Conventional drug discovery is expensive, time-consuming, and prone to failure. Artificial intelligence has become a potent substitute over the last decade, providing strong answers to challenging biological issues in this field. Among these difficulties, drug-target binding (DTB) is a key component of drug discovery techniques. In this context, drug-target affinity and drug–target interaction are complementary and essential frameworks that work together to improve our comprehension of DTB dynamics. In this work, we thoroughly analyze the most recent deep learning models, popular benchmark datasets, and assessment metrics for DTB prediction. We look at the paradigm shift in the development of drug …

Deepssetracer 2.0: Improved Deep Learning Model Performance For Protein Secondary Structure Segmentation From Cryo-Em Maps, Bryan Hawickhorst, Thu Nguyen, Willy Wriggers, Jiangwen Sun, Jing He

Computer Science Faculty Publications

DeepSSETracer is a method for segmenting protein secondary structure from medium-resolution (5-10Å) cryogenic electron microscopy (cryo-EM) density maps. We conducted experiments and ablation studies to examine the effects of normalization methods, max-pooling, activation functions, and loss calculation region on DeepSSETracer. By combining multiple technical improvements, the performance of the new version, DeepSSETracer 2.0, was significantly enhanced compared to DeepSSETracer 1.1. On a set of 77 test cases, the weighted average per-voxel F1 score increased from 62.1% to 70.3% for helix detection, and from 47.8% to 62.5% for β-sheet detection. While each of the five modifications in the network enhanced the …