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Articles 1 - 30 of 48
Full-Text Articles in Life Sciences
Evaluating The Role Of Gras And Fadxdeba In Promoting Staphylococcus Aureus Adaptation To Host-Derived Fatty Acids Encountered At Sites Of Colonization And Infection, Robert C. Kuiack
Electronic Thesis and Dissertation Repository
Staphylococcus aureus is an opportunistic pathogen that asymptomatically colonizes 30% of humans, where it is well adapted to survive on the skin in the presence of innate defense mechanisms such as antimicrobial free fatty acids (FFA). While antimicrobial FFA function to inhibit the growth of S. aureus, they also provide a valuable source of lipids for membrane synthesis and energy production. We hypothesized that S. aureus possesses a novel antimicrobial FFA resistance pathway that is activated under conditions found on human skin, and that under these conditions, S. aureus can metabolize exogenous fatty acids to fuel growth and virulence …
Death Of A Bacterium: Exploring The Inhibition Of Staphylococcus Aureus By Burkholderia Cenocepacia., Tiffany Brandt
Death Of A Bacterium: Exploring The Inhibition Of Staphylococcus Aureus By Burkholderia Cenocepacia., Tiffany Brandt
Electronic Theses and Dissertations
Antimicrobial resistance is a phenomenon of increasing concern as antimicrobial overuse and misuse eliminate current therapeutic options, ushering society into a post-antimicrobial era. Antibiotic discovery and synthesis efforts are urgently needed to counter the increasing burden of antimicrobial resistance. Staphylococcus aureus is a causative agent of a variety of clinical manifestations including bacteremia, endocarditis, soft tissue infection, osteomyelitis, and device-related infections. S. aureus infection presents additional treatment challenges due to its capacity for biofilm formation, which is a mode of growth that confers protection from antibiotics and physical elimination, and the emergence of antibiotic resistant strains, including methicillin-resistant S. aureus …
Inhibition Of Staphylococcus Aureus Biofilm By Variovorax Paradoxus, Esther Gomez
Inhibition Of Staphylococcus Aureus Biofilm By Variovorax Paradoxus, Esther Gomez
University of the Pacific Theses and Dissertations
Staphylococcus aureus is one of the leading causes of fatal nosocomial infections. Often, S. aureus can grow as a biofilm which protects the population from the surrounding environment. Strains of S. aureus are resistant to virtually all known antibiotics on the market. Variovorax paradoxus is a soil microbe with many unusual metabolic activities. It has been previously observed that, V. paradoxus can inhibit the growth of S. aureus when in co-culture. In this work we report on inhibition of S. aureus biofilm formation by V. paradoxus due to a suspected inhibitory soluble factor.
A Functional Characterization Of The Omega (Ω) Subunit Of Rna Polymerase In Staphylococcus Aureus, Shrushti B. Patil
A Functional Characterization Of The Omega (Ω) Subunit Of Rna Polymerase In Staphylococcus Aureus, Shrushti B. Patil
USF Tampa Graduate Theses and Dissertations
In bacteria, RNA polymerase (RNAP) is a well-characterized and highly conserved multi-subunit enzyme complex responsible for transcription of DNA into RNA. The ω subunit (rpoZ/RpoZ), one of the smaller accessory subunits of RNAP, is often overlooked and under-studied, however, particularly in Gram-positive species. We have previously shown that deleting ω impacts the integrity of RNA polymerase in S. aureus, especially the β' subunit, and alters preference of the core enzyme for sigma factors, skewing heavily towards σB instead of the housekeeping σ factor. Consequently, this causes deregulation of myriad transcriptional processes, strongly rewiring gene expression circuits, and ultimately impairing the …
The Staphylococcus Aureus Lrgab Operon Encodes A Holin-Like Protein Involved In Pyruvate Transport, Jennifer L. Endres
The Staphylococcus Aureus Lrgab Operon Encodes A Holin-Like Protein Involved In Pyruvate Transport, Jennifer L. Endres
Theses & Dissertations
The Staphylococcus aureus cidABC and lrgAB operons encode a well-conserved family of proteins involved in programmed cell death (PCD) during biofilm development. Based on the structural similarities that CidA and LrgA share with bacteriophage holins, we have hypothesized that these proteins function by forming pores within the cytoplasmic membrane. To test this, we utilized a “lysis cassette” system that demonstrated the abilities of the cidA and lrgA genes to support bacteriophage endolysin-induced cell lysis. In addition, the CidA and LrgA proteins were shown to localize to the surface of membrane vesicles and cause leakage of small molecules, providing direct evidence …
Elucidating The Relationship Between Recombination Frequency And Antibiotic Resistance In Staphylococcus Aureus, Joseph R. Matthews
Elucidating The Relationship Between Recombination Frequency And Antibiotic Resistance In Staphylococcus Aureus, Joseph R. Matthews
Legacy Theses & Dissertations (2009 - 2024)
Staphylococcus aureus is a common commensal and opportunistic pathogen of humans. It causes a variety of diseases, ranging from skin and soft infections to life-threatening invasive diseases. Many strains of S. aureus have developed resistance to a variety of antibiotic classes, including many beta-lactams. The evolution and dissemination of antibiotic resistance in S. aureus lay in large part to its remarkable ability of acquiring DNA from other organisms through horizontal gene transfer and recombination. In this study, I elucidated the relationship between frequencies of recombination events and horizontally acquired antibiotic resistant genes in a population of S. aureus sampled from …
Transcriptomic And Functional Investigation Of Bacterial Biofilm Formation, Brooke R. Nemec
Transcriptomic And Functional Investigation Of Bacterial Biofilm Formation, Brooke R. Nemec
USF Tampa Graduate Theses and Dissertations
Staphylococcus aureus and Acinetobacter baumannii are two highly successful human pathogens, which have adopted very different, but effective survival strategies. The success of S. aureus is attributed to the tight regulation of an arsenal of virulence factors. Conversely, A. baumannii lacks what would be considered traditional virulence factors and, instead, has developed a high tolerance for environmental stress, which allows it to persist in unforgiving environments, including nosocomial settings and the human body. One common characteristic of these two organisms is their proclivity for biofilm formation. Herein, we discuss the diverse mechanisms governing biofilm formation for A. baumannii and S. …
Interregulation Between Msaabcr Operon And Ccpe To Determine Staphylococcal Metabolism And Virulence, Erin R. Cox
Interregulation Between Msaabcr Operon And Ccpe To Determine Staphylococcal Metabolism And Virulence, Erin R. Cox
Honors Theses
Staphylococcus aureus is a complex human pathogen that causes problems in both healthcare and community settings. Staphylococcus aureus is a gram-positive, sphere shaped bacterium that usually colonizes in the nasal cavity of healthy individuals. Staphylococcus aureus infections are a growing health concern due to its ability to produce virulence factors, such as pigmentation, protease production, and capsule formation. Two regulators in S. aureus virulence factors are msaABCR, which is a newly characterized operon, and ccpE. In order to determine the interaction between these two regulators in regulating virulence and metabolism in S. aureus, ccpE and ccpE/ …
Study Of The Role Of The Msaabcr Operon In Tricarboxylic Acid Cycle Activity And Persister Cell Formation In Staphylococcus Aureus, Karsen Motter
Study Of The Role Of The Msaabcr Operon In Tricarboxylic Acid Cycle Activity And Persister Cell Formation In Staphylococcus Aureus, Karsen Motter
Honors Theses
Staphylococcus aureus is an important human pathogen that causes wide arrays of infections ranging from minor skin infections to lethal systemic conditions such as infective endocarditis, osteomyelitis, sepsis and pneumonia. These systemic diseases are often difficult to treat due to the presence of persister cells. Persister cells are a phenotypic variant of the bacterial population that exhibit extreme and transient antibiotic tolerance accompanied by a transient halt in growth. Upon cessation of antibiotic treatment, however, persisters resume growth which results in recurrence of infections. This characteristic of persister cells therefore displays high clinical significance. In this study, we show the …
Elucidating The Role Of The Msaabcr Operon In Persister Cells Formation And Stress Response In Staphylococcus Aureus, Shanti Pandey
Elucidating The Role Of The Msaabcr Operon In Persister Cells Formation And Stress Response In Staphylococcus Aureus, Shanti Pandey
Dissertations
Staphylococcus aureus is a major human pathogen that causes lethal systemic conditions such as infective endocarditis, osteomyelitis, sepsis and pneumonia. Chronic in nature, these diseases are often refractory to the antibiotic treatment. Such recalcitrance is mainly caused due to the presence of persister cells, which are a bacterial subpopulation that exhibits extreme, yet transient antibiotic tolerance accompanied by a transient halt in the growth. However, upon cessation of antibiotic treatment, resumption in growth of persister cells causes recurrence of infections and treatment failure, displaying tremendous clinical significance. In this study, we show the involvement of the msaABCR operon in persister …
Increasing The Frequency Of Periodic Spatial Disturbance Decreases Surface Attachment Protein Expression In Staphylococcus Aureus, Ivana M. Barraza
Increasing The Frequency Of Periodic Spatial Disturbance Decreases Surface Attachment Protein Expression In Staphylococcus Aureus, Ivana M. Barraza
All HCAS Student Capstones, Theses, and Dissertations
Staphylococcus aureus is an opportunistic pathogen that can cause a variety of acute and chronic illnesses. The severity of these illnesses such as sepsis, necrotizing pneumonia, and toxic shock syndrome is measured through the virulence that S. aureus inflicts on its host. Methicillin-resistant S. aureus (MRSA) is commonly associated with secondary infections and is challenging to treat given the limited selection of antibiotics that are effective against it. Accordingly, novel approaches to reduce S. aureus pathogenicity are required. S. aureus regulates pathogenesis through a cell-to-cell communication system referred to as quorum sensing. Effective communication determines the production of two broad …
Investigating The Roles Of Lipids In Staphylococcus Aureus Infection, Xi Chen
Investigating The Roles Of Lipids In Staphylococcus Aureus Infection, Xi Chen
Dissertations
The Gram-positive bacterium Staphylococcus aureus is a major threat to public health and causes a multitude of infections, ranging from mild skin and soft infection, to more severe diseases including sepsis, osteomyelitis and infective endocarditis. As a successful pathogen, S. aureus employs various mechanisms to invade host tissues, evade immune responses, and survive in the host environment. One critical adaptive trait of S. aureus that promotes virulence and survival is the ability to maintain membrane homeostasis via flexible modifications to its lipid composition in response to the surrounding lipid environment. Phospholipids are the major component of the bacterial membrane and …
Staphylococcus Aureus Small Colony Variants Use Heme And Staphyloferrin B For Iron Acquisition, Izabela Z. Batko
Staphylococcus Aureus Small Colony Variants Use Heme And Staphyloferrin B For Iron Acquisition, Izabela Z. Batko
Electronic Thesis and Dissertation Repository
Iron is an essential nutrient for the bacterium Staphylococcus aureus. Wild-type S. aureus utilizes various iron acquisition systems to support growth in iron deplete conditions. S. aureus small colony variants (SCVs) are associated with chronic infections, yet the mechanisms by which these variants acquire iron are unknown. Mutation of hemB, involved in heme biosynthesis, generated a stable SCV that was auxotrophic for hemin and formed small colonies on solid media. To support growth under iron deplete conditions, my data revealed that S. aureus hemB synthesizes the siderophore staphyloferrin B, but not staphyloferrin A, although both siderophores could be …
Investigation Of The Growth And Survival Of Staphylococcus Aureus In Cftr-Deficient Macrophages, Bita Azad
Investigation Of The Growth And Survival Of Staphylococcus Aureus In Cftr-Deficient Macrophages, Bita Azad
Electronic Thesis and Dissertation Repository
Staphylococcus aureus and its small colony variants (SCVs) are commonly isolated from the lungs of cystic fibrosis (CF) patients. Although studies have suggested that cystic fibrosis transmembrane regulator (CFTR)-deficient macrophages are diminished in their ability to kill intracellular pathogens, whether this is true for CFTR-deficient macrophages infected with S. aureus or its SCVs is unknown. I employed gentamicin protection and eFluorÔ-670-based proliferation assays to assess the intracellular replication of S. aureus in CFTR inhibitor treated THP-1 and primary human macrophages, and in primary macrophages derived from CF patient blood. My work shows that the susceptibility of CFTR-deficient macrophages to the …
To Mid-Cell And Beyond: Characterizing The Roles Of Gpsb And Ypsa In Cell Division Regulation In Gram-Positive Bacteria, Robert S. Brzozowski
To Mid-Cell And Beyond: Characterizing The Roles Of Gpsb And Ypsa In Cell Division Regulation In Gram-Positive Bacteria, Robert S. Brzozowski
USF Tampa Graduate Theses and Dissertations
The bacterial cell division protein FtsZ is a tubulin homolog that forms a ring-like structure at the site of cell division in most bacterial species. There it acts as a scaffold, aiding in the recruitment of other divisome proteins to the site of cell division. Furthermore, studies focusing on the role of FtsZ treadmilling and septal peptidoglycan synthesis implicates that FtsZ plays a direct role in the ultimate closure of the division septum. Thus, many studies in the field of bacterial cell division have focused on FtsZ in terms of its spatial and temporal regulation as well as its ability …
Acid Resistance Mechanisms In Staphylococcus Aureus, Chunyi Zhou
Acid Resistance Mechanisms In Staphylococcus Aureus, Chunyi Zhou
Theses & Dissertations
Staphylococcus aureus is a leading cause of opportunistic infections in community and health care settings. To thrive in a great variety of environments, S. aureus has developed the capability of tolerating temporary pH changes, as well as resisting constant acid stress. To evaluate the impact of strong and weak acid stress on S. aureus, growth patterns of JE2 were monitored when cultured in chemically defined media (CDM) at various pH in the presence of hydrochloric acid (HCl), acetic acid, and lactic acid. Our results showed that S. aureus responds to strong and weak acids in different manners. S. aureus …
The Role Of Secreted Proteases In Regulating Disease Progression In Staphylococcus Aureus, Brittney D. Gimza
The Role Of Secreted Proteases In Regulating Disease Progression In Staphylococcus Aureus, Brittney D. Gimza
USF Tampa Graduate Theses and Dissertations
Staphylococcus aureus is a highly successful pathogen capable of producing a wealth of virulence factors in the human host. Of note, ten extracellular proteases are produced alongside these virulence factors and play a multifaceted role during infection. They not only cleave host proteins to promote bacterial invasion, immune evasion and survival, but also control disease progression by modulating the stability of self-derived pathogenic determinants. The importance of the secreted proteases modulating virulence factor stability is evidenced by our groups previous finding that a protease-null strain has a substantially increased infectious capacity in a murine model of sepsis; resulting from the …
Antibiotic Drug Discovery Targeting Bacterial Metabolism, Miranda J. Wallace
Antibiotic Drug Discovery Targeting Bacterial Metabolism, Miranda J. Wallace
Theses and Dissertations (ETD)
Over the last century, the use of antibiotics has enabled many advances in modern medicine, making life as we know it possible. In recent years, however, emerging bacterial resistance to virtually all major antibiotic classes has resulted in a worldwide increase in morbidity, mortality, and financial burden associated with drug resistant infections. The antimicrobial resistance crisis presents an urgent need for new antimicrobials with distinct mechanisms of action from existing drugs. The current pharmaceutical pipeline of new antibiotics is limited due to three obstacles: a lack of understanding of resistance mechanisms, a dearth of novel mechanisms of action among new …
Staphylococcus Aureus Evasion Of The Innate Immune System, James Paul Grayczyk
Staphylococcus Aureus Evasion Of The Innate Immune System, James Paul Grayczyk
Dissertations
Upon entry into the host, pathogens must overcome innate immunity in order to cause disease. The innate immune system represents a fast-acting initial line of defense to prevent infection. In order to withstand innate defenses, bacterial pathogens like the Gram-positive bacterium Staphylococcus aureus, produce a wide array of virulence factors that can inhibit innate immune cell recruitment and antimicrobial activity, or directly target and kill phagocytic leukocytes thereby facilitating pathogenesis. Infection with S. aureus can cause disease in virtually any tissue site and is a significant burden to human health. In this dissertation, we sought to understand how S. aureus …
The Surreptitious Survival Of The Emerging Pathogen Staphylococcus Lugdunensis In Macrophages Enhances S. Aureus Infection, David Watson
The Surreptitious Survival Of The Emerging Pathogen Staphylococcus Lugdunensis In Macrophages Enhances S. Aureus Infection, David Watson
Electronic Thesis and Dissertation Repository
Staphylococcus lugdunensis is an opportunistic pathogen that can cause invasive infections suggesting an ability to circumvent host immunity. S. lugdunensis was shown to resist killing and persist within macrophages and acetylation of its peptidoglycan is important for this survival. This was consistent in vivo, as S. lugdunensis resides inside Kupffer cells for at least 16 hours post-infection in mice. Despite its capability for survival, S. lugdunensis is unable to replicate within phagolysosomes. Inhibiting phagolysosomal effectors allows S. lugdunensis to initiate replication, after which the bacteria escape phagosomal containment. Moreover, intracellular S. lugdunensis augments the growth S. aureus during co-infection. Eight …
The Characterization Of The Transcription Factor Msab And Its Role In Staphylococcal Virulence, Justin Batte
The Characterization Of The Transcription Factor Msab And Its Role In Staphylococcal Virulence, Justin Batte
Dissertations
Staphylococcus aureus is a common human pathogen that is responsible for a wide range of infections, ranging from relative minor skin infections to life-threatening disease such as bacteremia, septicemia, and endocarditis. S. aureus possesses many different virulent factors that aid in its ability to cause this wide array of infections. One major virulence factor includes the production of capsular polysaccharide (CP). The production of CP plays a major role in the virulence response during infection specifically by providing S. aureus an antiphagocytic mechanism that allows the pathogen to evade phagocytosis during an infection. S. aureus has developed complex genetic regulatory …
Hospital And Meat Associated Staphylococcus Aureus And Their Biofilm Characteristics, Trevor Michael Wienclaw
Hospital And Meat Associated Staphylococcus Aureus And Their Biofilm Characteristics, Trevor Michael Wienclaw
Theses and Dissertations
Biofilm phenotypes were studied in 32 Staphylococcus aureus strains isolated from store-bought meats and 22 from diseased patients in hospitals. Of the meat-associated strains, 21 were methicillin-resistant Staphylococcus aureus (MRSA) and 11 were methicillin-susceptible Staphylococcus aureus (MSSA). The hospital-associated strains included 15 MRSAs and 7 MSSAs. We studied the robustness and composition of the biofilms produced by these strains. We found that on average hospital-associated strains form more robust biofilms than meat associated strains. The model often used to describe S. aureus biofilm composition includes two biofilm types defined by the presence or absence of polysaccharide intercellular adhesin (PIA), PIA-dependent …
Iron And Copper Homeostasis In Staphylococcus Aureus, Holly A. Laakso
Iron And Copper Homeostasis In Staphylococcus Aureus, Holly A. Laakso
Electronic Thesis and Dissertation Repository
All microorganisms require transition metals for key metabolic processes, thus during infection microbial access to essential metals is tightly regulated by the host in a process termed nutritional immunity. Iron acquisition is critical to the pathogenesis of the formidable human pathogen, Staphylococcus aureus, which utilizes heme-uptake systems and two high-affinity iron-scavenging siderophores, staphyloferrin A (SA) and staphyloferrin B (SB) for iron acquisition. In this study, I identify sbnI as encoding a transcription factor required for expression of genes in the sbn operon, the biosynthetic operon for SB synthesis. I also show that SbnI is a novel hemoprotein, where binding …
Identification And Characterization Of Farr And Fare As A Regulator And Effector Of Fatty Acid Resistance In Staphylococcus Aureus, Heba Alnaseri
Identification And Characterization Of Farr And Fare As A Regulator And Effector Of Fatty Acid Resistance In Staphylococcus Aureus, Heba Alnaseri
Electronic Thesis and Dissertation Repository
Although Staphylococcus aureus is exposed to antimicrobial fatty acids on the skin, in nasal secretions and in abscesses, specific mechanisms for regulating gene expression and intrinsic resistance in response to these fatty acids have not been reported. Through in vitro selection for increased resistance of S. aureus to linoleic acid, I identified fatty acid resistant clone FAR7, where a single nucleotide polymorphism caused a His121Tyr substitution in an uncharacterized member of the TetR family of transcriptional regulators, which is divergently transcribed from a gene encoding a member of the resistance-nodulation-division superfamily of multi-drug efflux pumps. I named these …
Development Of A Cholera Toxin Cta2/B Based Staphylococcus Aureus Vaccine To Prevent Bovine Mastitis, Neha Misra
Development Of A Cholera Toxin Cta2/B Based Staphylococcus Aureus Vaccine To Prevent Bovine Mastitis, Neha Misra
Boise State University Theses and Dissertations
Staphylococcus aureus is an important pathogen causing chronic and invasive disease worldwide. This bacterium is a leading cause of community and hospital acquired infections in humans, and is also known to infect wild and domestic animals. Bovine mastitis, or inflammation of the udder, is one of the most economically relevant diseases of the dairy industry, with a high incidence worldwide. S. aureus is a major etiological agent causing this disease. S. aureus mastitis is highly contagious and difficult or impossible to treat. Management practices at dairy farms, that include good sanitation and antibiotic use, have been partially successful in reducing …
Anti-Staphylococcal Activity Of Variovorax Paradoxus Eps, Patricia Holt-Torres
Anti-Staphylococcal Activity Of Variovorax Paradoxus Eps, Patricia Holt-Torres
Electronic Theses, Projects, and Dissertations
Variovorax paradoxus EPS is a gram-negative rod isolated from the sunflower rhizosphere at CSUSB. Preliminary research has shown that Variovorax paradoxus EPS has anti-staphylococcal activity in liquid and solid co-culture. Anti-staphylococcal activity of Wild type and V. paradoxus EPS 𝚫4519 on 0.5% YE agar with embedded S. aureus AH1710 supports the idea that a soluble molecule is responsible for this activity, as the agar acted as a physical barrier between V. paradoxus EPS and S. aureus colonies. Preliminary genetic analysis of V. paradoxus EPS identified three loci that suitable candidates for the synthesis of a potential anti-staphylococcal small molecule. …
Examination Of Bcaa Transport And Synthesis In Staphylococcus Aureus, Julienne Kaiser
Examination Of Bcaa Transport And Synthesis In Staphylococcus Aureus, Julienne Kaiser
Electronic Thesis and Dissertation Repository
Staphylococcus aureus is a human pathogen capable of causing infections that range from mild skin and soft tissue infections to severe infections of the bone, muscle, heart, and lung. To survive and thrive in such diverse host environments, S. aureus must maintain sufficient levels of metabolites and cofactors to support virulence determinant production and replication. The branched-chain amino acids (BCAAs; Ile, Leu, Val) represent an important group of nutrients for S. aureus metabolism, as they are required for protein synthesis and synthesis of membrane branched-chain fatty acids (BCFAs), which are important for S. aureus environmental adaptation. Moreover, the BCAAs are …
Redirection Of The Immune Response To Staphylococcus Aureus Biofilm Infection, Anna G. Staudacher
Redirection Of The Immune Response To Staphylococcus Aureus Biofilm Infection, Anna G. Staudacher
Theses & Dissertations
Staphylococcus aureus (S. aureus) is a leading cause of community- and healthcare-associated infections and has a propensity to form biofilms. Biofilm infections are recalcitrant to host immune-mediated clearance as well as antibiotics, making them exceptionally difficult to eradicate. The biofilm environment has been shown to skew the host immune response towards an anti-inflammatory phenotype, characterized by alternatively activated macrophages, recruitment of myeloid-derived suppressor cells (MDSCs), and minimal neutrophil and T cell infiltrates. Our laboratory has attempted to redirect the host immune response towards one that would favor bacterial clearance by employing strategies to augment pro-inflammatory mechanisms. One such …
Molecular Subtyping Of Staphylococcus Aureus Isolates From The U.P. Community For The Presence Of Toxin-Encoding Genes, Carol I. Kessel
Molecular Subtyping Of Staphylococcus Aureus Isolates From The U.P. Community For The Presence Of Toxin-Encoding Genes, Carol I. Kessel
All NMU Master's Theses
Staphylococcus aureus is the most common cause of human bacterial infections; however, humans can also be asymptomatically colonized with S. aureus. Asymptomatic carriers can potentially spread S. aureus infection to others. These infections can range from mild to severe. The pathology of a S. aureus infection is often dependent on which toxins are expressed and the virulence factors with which they are associated. One goal of this study was to isolate S. aureus from healthy, consenting adult volunteers who submitted nasal swabs for culture and qRT-PCR analysis to determine which strains are present in the community. This knowledge could …
Cytokine Expression, Cytoskeleton Organization, And Viability Of Sim-A9 Microglia Exposed To Staphylococcus Aureus-Derived Lipoteichoic Acid And Peptidoglycan, Erin Roberts
Browse all Theses and Dissertations
In these experiments, SIM-A9 microglia were exposed to Staphylococcus aureus cell wall components lipoteichoic acid (LTA) and peptidoglycan (PGN) at a concentration of 5 ug/mL for six, twelve, eighteen, and twenty-four hours and the cytokine expression, cytoskeleton organization, and cell viability of the cells were observed. Following LTA and PGN exposure, TNF-a; secretion increased at each time interval and was highest observed at 24 hours. No significant IL-10 secretion was detected. Over the 24 hour period, cell viability and cytotoxicity of LTA and PGN treatment groups were not significantly different from the control, indicating the observed inflammatory cytokine response was …