Biochemistry Commons^™

Characterization Of Lipids In Tenebrio Molitor Larvae And Pupae Under Various Extraction Methods, Nariman A. Ktil

Graduate Theses, Dissertations, and Problem Reports (ETD)

Tenebrio molitor, or the yellow mealworm is an edible insect widely recognized and consumed for its rich nutritional value. Mealworms are known for their flexible nature of adapting to various environmental conditions and being able to thrive under harsh conditions and low-value wastes. In this paper, our main goal was to investigate the mealworm’s ability to grow and develop while being reared on apple pomace, the biowaste from apple production, and the effect it would have on its nutritional value specifically its lipid profile. Then these reared insects were used for oil extraction and analyzing their fatty acid profiles. …

Investigating The Role Of Tryptophan In The Native Photo-Crosslinking Of A Cys-Containing Transmembrane Helix To A Membrane Lipid Double Bond, Michael Jay Telehany

Undergraduate Honors Theses

Our research group has previously discovered that a Cys residue within a transmembrane (TM) helix can directly photo-crosslink to a membrane lipid via an oxythiolation addition reaction to the double bond within the lipid, with a reaction yield of 10-20%. The pH-low Insertion Peptide (pHLIP) serves as our model TM helix, while the POPC lipid bilayer is our model membrane. We had long believed that the Trp residues within the sequence of pHLIP served as the key chromophore for this reaction, and thus they were essential for the formation of the TM helix-lipid adduct. To test this hypothesis, I synthesized …

Altered Lipid Metabolism In Apc-Driven Colorectal Cancer: The Potential For Therapeutic Intervention, Courtney O. Kelson, Yekaterina Y. Zaytseva

Markey Cancer Center Faculty Publications

Altered lipid metabolism is a well-recognized feature of solid cancers, including colorectal cancer. In colorectal cancer, upregulation of lipid metabolism contributes to initiation, progression, and metastasis; thus, aberrant lipid metabolism contributes to a poor patient outcome. The inactivating mutation of APC, a vital tumor suppressor in the Wnt signaling pathway, is a key event that occurs early in the majority of colorectal cancer cases. The potential crosstalk between lipid metabolism and APC-driven colorectal cancer is poorly understood. This review collectively highlights and summarizes the limited understanding between mutations in APC and the upregulation of Wnt/beta- catenin signaling and lipid metabolism. …

Assessing Lipid Composition Of Cell Membrane In Escherichia Coli Under Aerobic And Anaerobic Conditions, Isabelle Johnson

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Escherichia coli is a highly studied model organism that is tightly tied to the mammalian gastrointestinal system. This microorganism has the capability to be a beneficial gut microbe or a life-threatening pathogen. In this study, the lipid membrane of Escherichia coli was investigated using Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) to observe the change in its composition in aerobic and anaerobic conditions. Evidence of desaturation was discovered in the spectra, though more investigation is needed to understand the metabolic processes and drives that result in this change. Elucidation of these pathways in the future could result in …

Changes In Lipid Profiles Of Epileptic Mouse Model, Alicia Johnson, Ryan A. Grove, Deepak Madhavan, Cory Honsinger Thomas Boone, Camila Pereira Braga, Hannah Kyllo, Kaeli Samson, Timothy Simeone, Tomáš Helikar, Corrine K. Hanson, Jiri Adamec

Department of Biochemistry: Faculty Publications

Introduction—Approximately 1% of the world’s population is impacted by epilepsy, a chronic neurological disorder characterized by seizures. One-third of epileptic patients are resistant to AEDs, or have medically refractory epilepsy (MRE). One non-invasive treatment that exists for MRE includes the ketogenic diet, a high-fat, low-carbohydrate diet. Despite the KD’s success in seizure attenuation, it has a few risks and its mechanisms remain poorly understood. The KD has been shown to improve metabolism and mitochondrial function in epileptic phenotypes. Potassium channels have implications in epileptic conditions as they have dual roles as metabolic sensors and control neuronal excitation.

Objectives—The …

Bilirubin Nanoparticle Treatment In Obese Mice Inhibits Hepatic Ceramide Production And Remodels Liver Fat Content, Zachary A. Kipp, Genesee J. Martinez, Evelyn A. Bates, Agil B. Maharramov, Robert M. Flight, Hunter N. B. Moseley, Andrew J. Morris, David E. Stec, Terry D. Hinds Jr.

Markey Cancer Center Faculty Publications

Studies have indicated that increasing plasma bilirubin levels might be useful for preventing and treating hepatic lipid accumulation that occurs with metabolic diseases such as obesity and diabetes. We have previously demonstrated that mice with hyperbilirubinemia had significantly less lipid accumulation in a diet-induced non-alcoholic fatty liver disease (NAFLD) model. However, bilirubin’s effects on individual lipid species are currently unknown. Therefore, we used liquid chromatography-mass spectroscopy (LC-MS) to determine the hepatic lipid composition of obese mice with NAFLD treated with bilirubin nanoparticles or vehicle control. We placed the mice on a high-fat diet (HFD) for 24 weeks and then treated …

Oligomerization Of Amyloid-Β Peptide In The Presence Of Gangliosides–Implications For Alzheimer Disease, Sydney Boyd

Honors Theses

Alzheimer disease (AD) is a neurodegenerative disorder that leads to memory impairment and cognitive dysfunction in elderly populations worldwide. A key characteristic of AD is the formation of neuritic plaques composed of extracellularly deposited aggregates of amyloid-β (Aβ), an intrinsically disordered protein. Although Aβ fibrils were once thought to be the prime initiators of the disease, research has since been shifted to consider soluble, low molecular weight Aβ oligomers as the driving force behind AD toxicity. Due to its origin as a cleavage product of amyloid precursor protein (APP), an integral membrane protein, Aβ is known to perpetually interact with …

Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang

Dissertations, Theses, and Capstone Projects

Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …

Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky

Open Educational Resources

The goal of this preparatory textbook is to give students a chance to become familiar with some terms and some basic concepts they will find later on in the Anatomy and Physiology course, especially during the first few weeks of the course.

Organization and functioning of the human organism are generally presented starting from the simplest building blocks, and then moving into levels of increasing complexity. This textbook follows the same presentation. It begins introducing the concept of homeostasis, then covers the chemical level, and later on a basic introduction to cellular level, organ level, and organ system level. This …

Changes In Lipid Profiles Of Epileptic Mouse Mode, Alicia Johnson, Ryan A. Grove, Deepak Madhavan, Cory H.T. Boone, Camila Pereira Braga, Hannah Kyllo, Kaeli K. Samson, Kristina A. Simeone, Timothy A. Simeone, Tomáš Helikar, Corrine K. Hanson, Jiri Adamec

Department of Biochemistry: Faculty Publications

Introduction Approximately 1% of the world’s population is impacted by epilepsy, a chronic neurological disorder characterized by seizures. One-third of epileptic patients are resistant to AEDs, or have medically refractory epilepsy (MRE). One non-invasive treatment that exists for MRE includes the ketogenic diet (KD), a high-fat, low-carbohydrate diet. Despite the KD’s success in seizure attenuation, it has a few risks and its mechanisms remain poorly understood. The KD has been shown to improve metabolism and mitochondrial function in epileptic phenotypes. Potassium channels have implications in epileptic conditions as they have dual roles as metabolic sensors and control neuronal excitation.

Objectives …

Investigating Photosynthetic Stability: Relation Between Thylakoid Lipid Content And The Stability Of The Cytochrome B6f Complex, Marina Mehling

The Journal of Purdue Undergraduate Research

The cytochrome b₆f complex is an enzyme found in plants, cyanobacteria, and green algae that catalyzes the transport of electrons in the rate-limiting step of oxygenic photosynthesis. This dimeric complex has an extensive lipid architecture that is primarily composed of five distinct lipid classes: monogalactosyl diacylglycerol (MGDG), digalactosyl diacylglycerol (DGDG), phosphatidyl glycerol (PG), monoglucosyl diacylglycerol (GlcDG), and sulfoquinovosyl diacylglycerol (SQDG). While these lipid classes have been identified, their precise role in the function of the cytochrome complex are only beginning to be understood. Mechanisms describing the relation between thylakoid lipid content on the stability of the b_{6 …}

Size-Dependent Interactions Of Lipid-Coated Gold Nanoparticles: Developing A Better Mechanistic Understanding Through Model Cell Membranes And In Vivo Toxicity, Arek M. Engstrom, Ryan A. Faase, Joe E. Baio, Marilyn R. Mackiewicz, Stacey L. Harper

Chemistry Faculty Publications and Presentations

Introduction: Humans are intentionally exposed to gold nanoparticles (AuNPs) where they are used in variety of biomedical applications as imaging and drug delivery agents as well as diagnostic and therapeutic agents currently in clinic and in a variety of upcoming clinical trials. Consequently, it is critical that we gain a better understanding of how physiochemical properties such as size, shape, and surface chemistry drive cellular uptake and AuNP toxicity in vivo. Understanding and being able to manipulate these physiochemical properties will allow for the production of safer and more efficacious use of AuNPs in biomedical applications.
Methods and Materials: Here, …

Role Of Dyslipidemia On Lipid Metabolism In Maintenance Hemodialysis Patients, Eno Latifi

Wayne State University Dissertations

Maintenance hemodialysis (MHD) patients experience various abnormalities such as systemic inflammation (SI), oxidative stress (OS), and dyslipidemia (D). Defined as an imbalance of plasma lipids, lipoproteins, and lipid metabolism enzymes, D has been associated with a rise in morbidity and mortality within ESRD patients due to cardiovascular disease (CVD). However, the contribution of each of these parameters to D is poorly understood; moreover, the impact of the following parameters on dyslipidemia in different ethnicities is unknown. Hence, the objective of this study was to characterize D in a multi-ethnic cohort of ESRD patients. We hypothesized that the degree of dyslipidemia …

An Arabidopsis Protoplast Isolation Method Reduces Cytosolic Acidification And Activation Of The Chloroplast Stress Sensor Sensitive To Freezing 2, Allison C. Barnes, Christian G. Elowsky, Rebecca Roston

Department of Biochemistry: Faculty Publications

Chloroplasts adapt to freezing and other abiotic stresses in part by modifying their membranes. One key-remodeling enzyme is SENSITIVE TO FREEZING2 (SFR2). SFR2 is unusual because it does not respond to initial cold stress or cold acclimation, instead it responds during freezing conditions in Arabidopsis. This response has been shown to be sensitive to cytosolic acidification. The unique lipid products of SFR2 have also been detected in response to non-freezing stresses, but what causes SFR2 to respond in these stresses is unknown. Here, we investigate protoplast isolation as a representative of wounding stress. We show that SFR2 oligogalactolipid products accumulate …

Temperature And Polyunsaturated Fatty Acid’S Effect On Daphnia Magna Reproduction, Mark Albright

Electronic Theses and Dissertations

Organisms adapt to their environments by adjusting their biochemistry and physiology; such adaptation is limited by resource availability and physiological constraints. The freshwater crustacean Daphnia magna inhabits a wide range of environments and must survive and reproduce within a range of temperatures. One limit to low-temperature adaptation is thought to be the availability of unsaturated fatty acids necessary to maintain proper fluidity of cellular membranes. D. magna maintained at 10 ºC on a diet poor in unsaturated fatty acids have been observed to produce clutches that fail to develop. However, this has not been observed on a diet rich in …

Decreasing Phosphatidylcholine On The Surface Of The Lipid Droplet Correlates With Altered Protein Binding And Steatosis, Laura Listenberger, Elizabeth Townsend, Cassandra Rickertsen, Anastasia Hains, Elizabeth Brown, Emily G. Inwards, Angela K. Stoeckman

Chemistry Faculty Publications

Alcoholic fatty liver disease (AFLD) is characterized by an abnormal accumulation of lipid droplets (LDs) in the liver. Here, we explore the composition of hepatic LDs in a rat model of AFLD. Five to seven weeks of alcohol consumption led to significant increases in hepatic triglyceride mass, along with increases in LD number and size. Additionally, hepatic LDs from rats with early alcoholic liver injury show a decreased ratio of surface phosphatidylcholine (PC) to phosphatidylethanolamine (PE). This occurred in parallel with an increase in the LD association of perilipin 2, a prominent LD protein. To determine if changes to the …

Lipid Transport Required To Make Lipids Of Photosynthetic Membranes, Evan Labrant, Allison C. Barnes, Rebecca Roston

Department of Biochemistry: Faculty Publications

Photosynthetic membranes provide much of the usable energy for life on earth. To produce photosynthetic membrane lipids, multiple transport steps are required, including fatty acid export from the chloroplast stroma to the endoplasmic reticulum, and lipid transport from the endoplasmic reticulum to the chloroplast envelope membranes. Transport of hydrophobic molecules through aqueous space is energetically unfavorable and must be catalyzed by dedicated enzymes, frequently on specialized membrane structures. Here, we review photosynthetic membrane lipid transport to the chloroplast in the context of photosynthetic membrane lipid synthesis. We independently consider the identity of transported lipids, the proteinaceous transport components, and membrane …

Nanoscale Organization Of The Small Gtpase Rac1, Kelsey Maxwell

Dissertations and Theses (Open Access)

Rac1 is a small, guanine-nucleotide binding protein that cycles between an inactive GDP-bound and active GTP-bound state to regulate actin-mediated motility, migration, and adhesion. Plasma membrane (PM) localization is essential for its biological activity. Rac1 PM targeting is directed by a C-terminal membrane anchor that encompasses a geranylgeranyl-cysteine-methyl-ester, palmitoyl, and a polybasic domain (PBD) of contiguous lysine and arginine residues. Using high-resolution imaging combined with spatial mapping analysis, I found that Rac1 forms nanoclusters on the PM. Cycling between the GTP- and GDP-bound states, Rac1 forms nanoclusters that are non-overlapping, consequently undergoing guanine nucleotide-dependent spatial segregation. I further found that …

Harmonizing Lipidomics: Nist Interlaboratory Comparison Exercise For Lipidomics Using Srm 1950-Metabolites In Frozen Human Plasma, J Bowden, C Ulmer, C Jones, J Koelmel, L Abdullah, Houli Jiang, Michal Schwartzman, Amaury Cazenave-Gassiot, Antonio Checa, Michelle Cinel, Romain Colas, Serge Cremers, Edward Dennis, James Evans, Alexander Fauland, Jun Han, Houli Jiang, Michal Schwartzman

NYMC Faculty Publications

As the lipidomics field continues to advance, self-evaluation within the community is critical. Here, we performed an interlaboratory comparison exercise for lipidomics using Standard Reference Material (SRM) 1950-Metabolites in Frozen Human Plasma, a commercially available reference material. The interlaboratory study comprised 31 diverse laboratories, with each laboratory using a different lipidomics workflow. A total of 1,527 unique lipids were measured across all laboratories and consensus location estimates and associated uncertainties were determined for 339 of these lipids measured at the sum composition level by five or more participating laboratories. These evaluated lipids detected in SRM 1950 serve as community-wide benchmarks …

Therapeutic Exploitation Of Metabolic Checkpoints In Cancer Cells, Deven S. Patel

Dissertations, Theses, and Capstone Projects

During the G1 phase of the cell cycle, normal cells respond to growth factors and nutrients prior to entering S-phase to replicate its genome. We previously reported that the growth factor-mediated restriction point is distinguishable from a series of late G1 metabolic checkpoints mediated by essential amino acids (EAAs), the conditionally essential amino acid glutamine (Gln), and mTOR – the mammalian target of rapamycin. Mutations in genes encoding proteins that regulate G1 cell cycle progression are observed in virtually all cancers. We observed that cancer cells with K-Ras mutations bypass the late G1 Gln checkpoint when deprived of Gln and …

The Role Of N-Myc Downstream Regulated Gene 1 In Breast Cancer Lipid Metabolism, Christopher James Sevinsky

Legacy Theses & Dissertations (2009 - 2024)

Altered carbohydrate and lipid metabolism are increasingly well characterized hallmarks of aggressive breast cancers. While aerobic glycolysis, or “the Warburg effect”, is a well-established metabolic adaptation exploited by tumor cells, the understanding of unique aspects of cancer lipid metabolism lags behind. This is especially true regarding the coordination of complex lipid synthesis and trafficking pathways, which remains poorly understood. N-Myc Downstream Regulated Gene1 (NDRG1) is overexpressed in many solid tumors, but its function is unclear. The importance of NDRG1 is best exemplified by the effect of null mutations on human physiology: inactivating mutations give rise to the severe autosomal recessive …

Synthesis And Characterization Of Amide Linked Triazolyl Glycolipids As Molecular Hydrogelators And Organogelators, Guijun Wang, Anji Chen, Hari P. R. Mangunuru, Jayasudhan Reddy Yerabolu

Chemistry & Biochemistry Faculty Publications

Carbohydrate based small molecular gelators are important classes of compounds which can form useful soft materials with many practical applications. Although many different types of effective gelators have been reported, the rational design of a molecular hydrogelator is still challenging. In this research, we combined the structural features of two classes of monosaccharide based molecular gelators and obtained a new class of glycolipids that can function as molecular gelators. These new compounds were synthesized by introducing a triazole functional group to a protected 2-glucosamine through Cu(i) catalyzed azide/alkyne cycloaddition reaction (CuAAC). A series of eighteen new glycolipids containing 4,6-O …

Role Of Microrna-21 In Atherogenesis., Rihab Hamed-Berair

Electronic Theses and Dissertations

MicroRNA-21 (miR-21) is an evolutionarily conserved microRNA, abundant in most cardiovascular tissues. It has been implicated in the pathogenesis of several cardiovascular diseases including restenosis, myocardial infarction, and heart failure. However, little is known about the contribution of miR-21 in atherosclerosis. My data show that expression of miR-21 is increased by >1.5-fold in murine atherosclerotic lesions and by 1.5-2.0-fold in the macrophages of Western diet (WD)-fed LDLR-KO mice (for 12-20 weeks). In vitro, LDL, oxidized LDL, acetylated LDL and LPS induced miR-21 by 2-4-fold and down-regulated its target protein, PDCD4, in bone marrow-derived macrophages. Basally, macrophages isolated from miR-21-KO …

Placental ‘€˜Omics’€™ Study To Understand The Pathogenesis Of Preeclampsia, Komal Kedia

Theses and Dissertations

Preeclampsia (PE) is a potentially fatal complication of pregnancy characterized by an increase in blood pressure (>140/90 mmHg) and proteinuria (>300 mg/24 hrs), often accompanied by edema. Symptoms of PE start after 20 weeks of gestation. If PE remains untreated, it can lead to eclampsia, grand-mal seizures responsible for most fatalities. PE is believed to affect 2-10% of pregnancies worldwide, and claims the lives of over 75,000 mothers and 500,000 newborns yearly. No therapeutic agents have been developed to prevent or cure PE. Part of the reason for this is the absence of a complete understanding of the …

Bacterial Forensics: Revolutionizing Biochemical Analysis, Caitlin Cain

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Eva Childrey is a junior forensic science and chemistry double major working in Dr. Eh- rhardt’s research laboratory at VCU. The main goal of the research conducted in this laboratory is to explore the lipid profiles of different bacterial species.

Fatty Acid Recovery And Identification In Mars Analogue Soil Samples, Kimberly E. Lykens

STAR Program Research Presentations

A primary goal of NASA’s Mars 2020 mission is to gather and store samples of Mars soil that could possibly be returned to Earth in a future mission for investigations into past or present life. In years leading up to a potential sample return mission on Mars and potentially other worlds, samples taken from Chile’s Atacama Desert, the most arid, biologically limited desert in the world, are valuable in developing a capacity for biosignature detection, specifically when exploring fatty acid abundance. Eighteen samples were collected from two sites in the Atacama characterized by biological soil crusts (BSC). BSCs are areas …

Validating A Method For Measuring Protein Domain And Lipid Binding Interactions Using Luciferase Fusion Proteins, Dezaray E. Thoen

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Expression And Functional Analysis Of Lipids And Glycolipids From The Mammal-Dwelling Stages Of Trypanosoma Cruzi, Felipe Gazos Lopes

Open Access Theses & Dissertations

Trypanosoma cruzi is the causative agent of the life-threatening Chagas disease, in which increased platelet aggregation related to myocarditis is observed. Platelet-activating factor (PAF) is a potent intercellular lipid mediator and second messenger that exerts its activity through a PAF-specific receptor (PAFR). Previous data from our group suggested that T. cruzi synthesizes a phospholipid with PAF-like activity. The structure of T. cruzi PAF-like molecule, however, remains elusive. Here, we have purified and structurally characterized the putative T. cruzi PAF-like molecule by electrospray ionization-tandem mass spectrometry (ESI-MS/MS). Our ESI-MS/MS data demonstrated that the T. cruzi PAF-like molecule is actually a lysophosphatidylcholine …

Lipid Dependence In Ras-Driven Tumors, Darin Salloum

Dissertations, Theses, and Capstone Projects

Over past decade, metabolic alterations in cancer cells have received a substantial amount of interest. It had been established that cancer cells undergo a significant amount of metabolic alterations, and some of these alterations are similar to those in normal highly proliferative cells. However, it is becoming more apparent that many of the metabolic alterations are specific to particular oncogenic signaling pathways. Although altered metabolic machinery makes cancer cells more efficient at promoting growth when nutrients are supplied at the sufficient amounts, the dependency of cancer cells on particular metabolic reprogramming deems cancer cells susceptible to disruptions within metabolic network. …

Raman Spectroscopic Analysis Of Human Skin Tissue Sections Ex-Vivo: Evaluation Of The Effects Of Tissue Processing And Dewaxing, Syed Mehmood Ali, Franck Bonnier, Ali Tfayli, Helen Lambkin, Kathleen Flynn, Vincent Mcdonagh, Claragh Healy, Thomas Lee, Fiona Lyng, Hugh Byrne

Articles

Raman spectroscopy coupled with K-means clustering analysis (KMCA) is employed to elucidate the biochemical structure of human skin tissue sections, and the effects of tissue processing. Both hand and thigh sections of human cadavers were analysed in their unprocessed and formalin fixed paraffin processed (FFPP) and subsequently dewaxed forms. In unprocessed sections, KMCA reveals clear differentiation of the stratum corneum, intermediate underlying epithelium and dermal layers for sections from both anatomical sites. The stratum corneum is seen to be relatively rich in lipidic content; the spectrum of the subjacent layers is strongly influenced by the presence of melanin, while that …