Cell and Developmental Biology Commons^™

Physical Ablative Methods And Cancer Cell Death: Implications For Immunity And Therapies, Alessandra Rossi, Claudia Muratori

Bioelectrics Publications

Surgery has traditionally been a cornerstone in cancer treatment, yet its feasibility can be limited by factors such as tumor location and patient health conditions. When surgery is not viable, thermal and pulsed electric field (PEF)-based ablation technologies offer valuable alternatives. Emerging evidence suggests that these approaches not only target tumors effectively but also stimulate antitumor immune responses. In this review, we begin by examining the distinctive features of hyperthermic treatments (radiofrequency and microwave ablation), cryoablation, and PEF-technologies. Subsequently, we discuss the mechanisms of cell death, stress responses, and release of danger signals triggered by these diverse ablation technologies. Finally, …

Synthesis, Characterization, And Biological Activity Of Ni(Ii) And Co(Iii) Thiosemicarbazone Complexes As Potential Anticancer Agents, Jack Martin

Pitzer Senior Theses

The mechanics by which Reactive Oxygen Species work is an area of great interest given ROS’s wide range of biological applications. From cell signaling and mitochondrial regulation to pathogenesis and tumor cell death, varying concentrations of ROS in a system can lead to a whole host of positive and negative effects. In a similar vein, thiosemicarbazones are known to be equally useful for their myriad of antibacterial, antifungal, antiviral, and antitumoral effects. They have been at the core of the pharmaceutical world or the better part of the last century. The purpose of this work is to synthesize, characterize and …

Optimizing Decision-Making In A Cerebral Palsy Model Using Reinforcement Learning, Richard Ampah

Pitzer Senior Theses

This study presents an original interdisciplinary investigation into how reinforcement learning (RL) can model motor and cognitive defects and potentially improve motor and cognitive functions in individuals with cerebral palsy (CP), a non-progressive neurological disorder that impairs movement and adaptability. Integrating computational neuroscience and machine learning, the research applies policy gradient methods and Markov Decision Processes (MDPs) to simulate adaptive learning in agents with and without CP-related constraints.

The central aim is to compare the cumulative rewards of optimal policies, derived from value iteration, and human-like learning policies using the REINFORCE algorithm, both with and without the Bellman baseline. The …

Impact Of Hiv-2 Rod9 Vpx Mutations On Samhd1 Degradation And Vpx Nuclear Trafficking, Tolulope R. Oladimeji

All Graduate Theses, Dissertations, and Other Capstone Projects

Human Immunodeficiency Virus (HIV) is a leading cause of death in many parts of the world. HIV-2, endemic to West Africa, has infected over 2 million people globally. A key difference between HIV-2 and the more widespread HIV-1 is the HIV-2 protein Vpx, which facilitates infection in non-dividing cells by targeting SAMHD1, a host innate immune protein, for proteasomal degradation. This research aims to identify specific amino acid residues in HIV-2 ROD9 Vpx that are essential for mediating SAMHD1 degradation by the proteosome. I hypothesize that amino acid residues located in the C-terminal region of Vpx play a critical role …

The Impact Of Maternal Environmental Exposures On The Immune Landscape Of The Maternal-Fetal Interface, Heather E. True

Theses and Dissertations--Pharmacy

Maternal environmental exposures and inflammation are known to impact fetal development in utero as well as increase the risk for chronic diseases later in life. Therefore, it is essential that we understand how the maternal environment alters placental structure and immune function.

Therefore, we isolated fetal (chorionic villous) tissues from the placentas of healthy pregnant participants (control) and those with inflammatory conditions, including SARS-COV-2 infection, pregravid obesity, and opioid use disorder. Isolated placental leukocytes were subjected to a series of assays to uncover the phenotypic, functional, and transcriptional (single-cell RNA-sequencing) landscape of placental immune cells. Additional placental tissues were subjected …

Effects Of Round-Up On The Environment, Sandra J. Marcu

Journal of Earth and Life Science

Many people around the world have used and still currently use Roundup but are unaware of the effects it has on the environment. Roundup is a spray on application weedkiller that is widely used around the world today both residentially and commercially. It enables its user to grow a garden or a field of crops with a no-tilling approach to eliminate weeds. It is a well-known and popular choice for killing weeds that has been around since the mid 1970’s (Oca, 2017). John Franz, a Monsanto scientist discovered that glyphosate (main ingredient in Roundup) was an herbicide or weedkiller, and …

Characterizing A Rad23 Dependent Ultraviolet Radiation Resistance In Tetrahymena Thermophila, Emma June Liimatta

Graduate Theses/Dissertations

In 2020, 10 million deaths were attributed to cancer, with multidrug resistance being responsible for over 90% of deaths in cancer patients receiving treatment. This study utilized the model organism Tetrahymena thermophila to study how cells become resistant to Ultraviolet Radiation (UV) radiation, a process similar to multidrug resistance, specifically focusing on the nucleotide excision repair and ubiquitin shuttle protein Rad23. The National Cancer Institute documented 30-60% of cancers tested had a mutation in RAD23. Knockdown of RAD23 in Tetrahymena thermophila demonstrated a UV resistance phenotype with decreased nucleotide excision repair and differential expression of proteins active within caspase-independent …

The Role Of Host Factor Sptbn1 In Hiv-1 Capsid Uncoating In Human Microglial Cells, Callie Marie Fry

Graduate Theses/Dissertations

HIV-1 is the virus that causes acquired immunodeficiency syndrome (AIDS), and currently, there is no cure once an individual is infected. The development of new drugs targeting HIV-1 replication steps is essential for keeping viral loads low or undetectable to prevent further transmission. An attractive replication step for new drug targets is viral capsid uncoating, where the virus loses the protein structure encapsulating the genome. The exact mechanism of capsid uncoating is unknown; however, several host-factors may be involved including protein SPTBN1. Recent studies have shown a significant decrease in viral infectivity when SPTBN1 is knocked down, yet its role …

Cardiac Injury Regulates Neuroinflammation Through Extracellular Vesicle–Mediated Heart-Brain Crosstalk, Qingxuan Li, Ramzi H. Hamdalla, Neha Dhyani, Lijun Sun, Lie Gao, Tara L. Rudebush, Irving H. Zucker, Changhai Tian

Toxicology and Cancer Biology Faculty Publications

Cognitive impairment is common in heart failure patients, contributing to morbidity and mortality. This impairment may be linked to neuroinflammation in heart failure. However, the primacy of the heart-brain axis remains to be completely understood. Here, we elucidate the potential effects of myocardial injury on pathways and inflammatory mediators responsible for cognitive impairment using a rodent myocardial injury model. The results demonstrate direct extracellular vesicle (EV)-mediated heart-brain crosstalk and the glial uptake of cardiac EVs. In addition, brain inflammation was also elicited following myocardial injury. Moreover, cardiac EVs promote brain microglial cell activation in vitro, potentially mediated by EV-enriched micro-RNAs …

Exploring The Links Among Brain Iron Accumulation, Cognitive Performance, And Dietary Intake In Older Adults: A Longitudinal Mri Study, Valentinos Zachariou, Colleen A. Pappas, Christopher E. Bauer, Elayna R. Seago, Brian T. Gold

Neurology Faculty Publications

This study evaluated longitudinal brain iron accumulation in older adults, its association with cognition, and the role of specific nutrients in mitigating iron accumulation. MRI-based, quantitative susceptibility mapping estimates of brain iron concentration were acquired from seventy-two healthy older adults (47 women, ages 60–86) at a baseline timepoint (TP1) and a follow-up timepoint (TP2) 2.5–3.0 years later. Dietary intake was evaluated at baseline using a validated questionnaire. Cognitive performance was assessed at TP2 using the uniform data set (Version 3) neuropsychological tests of episodic memory (MEM) and executive function (EF). Voxel-wise, linear mixed-effects models, adjusted for longitudinal gray matter volume …

Scientific Writing: A Guide From Data To Draft, Kristin M. Klucevsek

Open Education Materials

Textbook for ENGL302W (Scientific Writing)

CC BY-NC-SA (2025)

Caspases Protect Against Hyperglycemia Induced Necroptosis-Like Cell Death In Brain Endothelial Cells, Aleena S. Mathew

Theses and Dissertations

Acute diabetes characterized by high spikes in blood glucose levels in association with severe hyperglycemia can lead to an increased risk of ischemic stroke in the brain. To better understand high blood glucose levels, hyperglycemia, in the brain we explored its effects on endothelial cells. Endothelial cells line the inner walls of blood vessels and are directly impacted in hyperglycemia. Brain endothelial cells are a major component of the blood brain barrier (BBB) which tightly regulates the brain’s microenvironment. The type of cell death such as apoptosis, caspase dependent, or necroptosis, caspase independent, can exacerbate diabetes associated complications. There is …

Gain-Of-Function Tp53 Mutations Induce Non-Canonical Nf-Κb Transcriptional Targets To Promote Tumor Development, Kelsey A. Yutan

Scripps Senior Theses

Background: Gain-of-function TP53 mutations have previously been shown to induce chromosomal instability (CIN) in cancer cells, triggering the cGAS-STING innate immune response and subsequently activating the non-canonical NF-κB (NC-NF-κB) signaling pathway. This signaling cascade promotes cancer cell metastasis and an immunosuppressive tumor microenvironment (TME), significantly impacting tumor development and progression. However, the precise downstream mechanisms by which the mutp53-CIN-cGAS-STING-NC-NF-κB signaling pathway facilitates tumor development and progression remain poorly understood. Here, our objective was to identify direct downstream targets of mutp53-CIN-cGAS-STING-induced NC-NF-κB signaling that potentially impact the TME to promote the development and progression of oral squamous cell carcinoma.

Methods …

Environmental Pollution And Early-Life Metabolic Programming, Lisa Koshko

Wayne State University Dissertations

Substantial evidence demonstrates that parental pollutant exposures can induce harmful health effects in the offspring, including the predisposition to Type II Diabetes. As rates of Type II Diabetes continue to rise in younger populations, a crucial gap lies in understanding the role of parental influence in the etiology of later-life metabolic disease. Therefore, the central goal of this work was to determine how early life exposure to smoking level benzene, an endocrine-disrupting air pollutant, affects the metabolic health of offspring, and to identify potential developmental mechanisms involved in disease susceptibility. This goal was achieved using two models of early life …

Examining The Effect Of A High Fat Diet On The Expression Of Adipokines In A Murine Model Of Barrett's Esophagus, Saagar A. Shah

Honors Undergraduate Theses

Chronic acid reflux results in injury to the esophagus and the development of Barrett’s Esophagus (BE). BE elevates the lifetime risk for a patient to develop Esophageal Adenocarcinoma (EAC). Clinically, one of the main risk factors for BE and EAC is obesity, which alters the secretion of inflammatory cytokines by adipocytes, also referred to as adipokines. Conflicting reports have been made to the expression of adipokines and their receptors in the progression to esophageal cancer. Utilizing an inflammation-based mouse model for BE, we hypothesize that alterations in the expression of adipokines and their receptors favor an inflammatory environment associated with …

Biomechanics Of The Atherosclerotic Lipidome: (Un)Expected Statin Interactions And Membrane Remodelling, Ethan M. Fong

Pomona Senior Theses

Statins interact with lipid membranes in ways that shape their pharmacokinetics, off-target effects, and pleiotropic actions, yet these interactions' mechanical and biophysical consequences remain poorly understood. This thesis employs a combination of surface plasmon resonance (SPR), quartz crystal microbalance with dissipation monitoring (QCM-D), and rheological modelling to characterize how representative statins intercalate within biomimetic supported lipid bilayers (SLBs) of healthy and diseased composition. SPR reveals that lipophilic statins exhibit higher apparent affinities and slower dissociation kinetics, especially in cholesterol- and anionic lipid-rich membranes. QCM-D analyses demonstrate that statins alter membrane mass, dissipation, and interfacial stiffness in a statin- and membrane-dependent …

Pharmacological Or Genetic Inhibition Of Ltcc Promotes Cardiomyocyte Proliferation Through Inhibition Of Calcineurin Activity, Lynn A. C. Devilée, Abou Bakr M. Salama, Jessica M. Miller, Janice D. Reid, Qinghui Ou, Nourhan M. Baraka, Kamal Abou Farraj, Madiha Jamal, Yibing Nong, Todd K. Rosengart, Douglas A. Andres, Jonathan Satin, Tamer M. A. Mohamed, James E. Hudson, Riham R. E. Abouleisa

Markey Cancer Center Faculty Publications

Cardiomyocytes (CMs) lost during ischemic cardiac injury cannot be replaced due to their limited proliferative capacity. Calcium is an important signal transducer that regulates key cellular processes, but its role in regulating CM proliferation is incompletely understood. Here we show a robust pathway for new calcium signaling-based cardiac regenerative strategies. A drug screen targeting proteins involved in CM calcium cycling in human embryonic stem cell-derived cardiac organoids (hCOs) revealed that only the inhibition of L-Type Calcium Channel (LTCC) induced the CM cell cycle. Furthermore, overexpression of Ras-related associated with Diabetes (RRAD), an endogenous inhibitor of LTCC, induced CM cell cycle …

Mir-27a-3p Regulates Intestinal Cell Proliferation And Differentiation Through Wnt/Β-Catenin Signalling, Chang Li, Yuning Zhou, Yinping Jiang, Zhijie Yin, Heidi L. Weiss, Qingding Wang, B. Mark Evers

Markey Cancer Center Faculty Publications

Intestinal stem cells differentiate into absorptive enterocytes, characterised by increased brush border enzymes such as intestinal alkaline phosphatase (IAP), making up the majority (95%) of the terminally differentiated cells in the villus. Loss of integrity of the intestinal epithelium plays a key role in inflammatory diseases and gastrointestinal infection. Here, we show that the intestinal microRNA (miR)-27a-3p is an important regulator of intestinal epithelial cell proliferation and enterocyte differentiation. Repression of endogenous miR-27a-3p leads to increased enterocyte differentiation and decreased intestinal epithelial cell proliferation in mouse and human small intestinal organoids. Mechanistically, miR-27a-3p regulates intestinal cell differentiation and proliferation at …

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 …

Characterization Of The Overexpression Of Reca Homologs Rad51 And Dmc1 In Tetrahymena Thermophila, Jianna M. Cox

Graduate Theses/Dissertations

RecA homologs, Dmc1 and Rad51, work to repair DNA double-strand breaks (DSBs) within the cell through the recombination of homologous sections of DNA. Dmc1 works to repair programmed DSBs through meiotic recombination, while Rad51 functions to repair both meiotic and non-meiotic DSBs, the latter repaired through the process of homologous recombination repair (HHR). Chemotherapeutics, exogenous agents, work to form DSBs in cancer cells, attempting to inhibit the cell’s growth. A hyper recombinant phenotype is often seen in cancer cells due to the overexpression of RAD51, leading to drug resistance, the persistence of cancers, and an overall poor patient outcome. …

Leukocyte Infiltration Profiles At The Site Of Intradermal Injection Of Silikon-1000 In Scleroderma-Prone Ucd200/206 And Healthy White Leghorn Chickens, Katee L. Johnson, Jossie M. Santamaria, Chrysta N. Beck, Gisela F. Erf

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Intradermal injections of silicone-based fillers for the face and body may cause chronic inflammation and fibrotic reactions in some individuals. Chickens from the UCD 200/206 White Leghorn (WL) line spontaneously develop a fibrotic autoimmune disease known as scleroderma/systemic sclerosis (SSc). Using the SSc-prone UCD and healthy WL chickens, a longitudinal study was conducted to examine the cellular inflammatory responses to intradermal (i.d.) injections of sterile SILIKON-1000. Specifically, the pulp (a skin derivative) of growing feathers (GFs) was i.d. injected with sterile SILIKON-1000 or phosphate-buffered saline (PBS) as injection control (8 and 3 birds/line, respectively; 10 µL/GF; 20 GFs/bird). Two GFs …

Intercellular Mitochondrial Transfer Contributes To Microenvironmental Redirection Of Cancer Cell Fate, Julie Sofie Bjerring, Yara Khodour, Emilee Anne Peterson, Patrick Christian Sachs, Robert David Bruno

School of Medical Diagnostics & Translational Sciences Publications

The mammary microenvironment has been shown to suppress tumor progression by redirecting cancer cells to adopt a normal mammary epithelial progenitor fate in vivo. However, the mechanism(s) by which this alteration occurs has yet to be defined. Here, we test the hypothesis that mitochondrial transfer from normal mammary epithelial cells to breast cancer cells plays a role in this redirection process. We evaluate mitochondrial transfer in 2D and 3D organoids using our unique 3D bioprinting system to produce chimeric organoids containing normal and cancer cells. We demonstrate that breast cancer tumoroid growth is hindered following interaction with mammary epithelial cells …

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 …

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%), …

The Role Of Tgf-Beta Superfamily Members In Immune Homeostasis And Disease, Natalie Eva Nieuwenhuizen, Ioannis Eleftherianos, Piotr Jan Kraj, Maria Semitekolou

Biological Sciences Faculty Publications

[Introduction] The Transforming Growth Factor beta (TGF-beta) superfamily, encompassing molecules such as TGFs, activins, Bone Morphogenetic Proteins (BMPs), Growth/Differentiation Factor (GDFs) and Nodals, represents the largest family of growth and differentiation factors, playing crucial roles in developmental and physiological processes across animal species (1). These molecules are integral to tissue homeostasis and cell fate determination. Among them, TGF-beta is particularly noted for its regulatory influence on immune responses and tissue fibrosis (2, 3). Recent research has expanded our understanding of the immune functions of other superfamily members, including activin A and BMPs (4). These molecules signal through receptor complexes composed …

Repositioning Antimalarial Drugs As Anticancer Agents: Focus On Tafenoquine, Chris Barton

Funded Scholarship

Due to the expensive and lengthy process of drug design and approval, drug repurposing (or repositioning) has become another option for identifying preexisting molecules that may be used for alternative purposes. Recently, some antimalarial compounds have been shown to display efficacy against cancer cell proliferation. In this study, we provide evidence to suggest that multiple preexisting antimalarial drugs can reduce the viability of human cancer cells in culture. Furthermore, we provide the first evidence that one antimalarial, Tafenoquine (LD50 = 9.6 μM in HCT116 cells), is capable of decreasing viability with an efficacy comparable to Etoposide (LD50 = 15.2 μM …

Dengue Virus Modulates Critical Cell Cycle Regulatory Proteins In Human Megakaryocyte Cells, Swarnendu Basak, Shovan Dutta, Supreet Khanal, Girish Neelakanta, Hameeda Sultana

Biological Sciences Faculty Publications

Suppression of human megakaryocytes by dengue virus (DENV) infection significantly reduces the platelet count that eventually leads to thrombocytopenia, severe dengue and death. To understand DENV interactions with megakaryocytes, we investigated the cell cycle in leukemic human megakaryocytic in vitro cell line (MEG-01 cells). Megakaryocytes are known for complex endomitotic cell cycle leading to their polyploidy state. Our study shows that DENV uses these polyploid cells for its replication. Understanding the modulation of DENV-mediated cell cycle regulation in megakaryocytes is therefore highly important. We show that DENV2 (serotype 2) infection significantly modulates cell cycle signaling. Our protein profile microarray data …

Xanthine Oxidoreductase, Uric Acid, And Iron Homeostasis: Discovering A Therapeutic Vulnerability In Breast Cancer, Matthew G. Chapa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Breast cancer remains the most frequently diagnosed malignancy and the leading cause of cancer related deaths in women. This is primarily due to distant metastases, which highlight the necessity to understand factors that contribute to breast cancer progression. Emerging evidence associates decreased tumor xanthine oxidoreductase (XOR) expression with a poorer prognosis, increased recurrence, and a more aggressive phenotype. While healthy liver, intestines, kidneys, and breast tissue have robust XOR expression and activity, there is a tendency for this to be ablated in carcinogenesis. This dissertation investigates XOR's role in breast cancer and identifies its product, uric acid (UA), as possessing …

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 …