L-Pipecolic Acid Production In Thra Knockout Escherichia Coli,
2018
Faculty of Sciences
L-Pipecolic Acid Production In Thra Knockout Escherichia Coli, Suttilak Khuanwilai
Chulalongkorn University Theses and Dissertations (Chula ETD)
L-pipecolic acid (L-PA) is a non-proteinogenic amino acid, however, it is an important precursor and a key ingredient of many pharmaceutically compound syntheses such as immunosuppressants and anesthetics. The production of amino acids via fermentation of microorganisms are getting attention, one of the widely used is an engineered E. coli. L-PA production in the engineered E. coli uses L-lysine in its cell as a substrate. This research aimed to increase L-PA production by thrA knockout. The thrA encodes homoserine dehydrogenase I, the enzyme which draws the intermediate in L-lysine biosynthesis pathway to synthesize L-threonine. The group II intron insertion was …
Effects Of Mutations Of Levansucrase From Bacillus Licheniformis Rn-01 On Levan Oligosaccharides Binding,
2018
Faculty of Science
Effects Of Mutations Of Levansucrase From Bacillus Licheniformis Rn-01 On Levan Oligosaccharides Binding, Thassanai Sitthiyotha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Produced by levansucrase that uses sucrose as a substrate, levan and levan oligosaccharides (GFn) have potential applications in food and pharmaceutical industries such as prebiotics, anti-obesity and anti-tumor agents. Previous study reported that N251A and N251Y mutants of levansucrase from Bacillus licheniformis RN-01 could effectively produce short-chain oligosaccharides upto GF3, instead of long-chain levan synthesis. This study hypothesized that these mutations probably reduced GF3 binding affinity in the active site of levansucrase that contains fructosyl-Asp93 intermediate and caused GF3 to be in an unfavorable orientation for transfructosylation; therefore, levansucrase could not effectively extend GF3 to GF4. However, these mutations probably …
Transcriptome Of Rice Oryza Sativa L. Over-Expressing Oscam1-1 Gene And Characterization Of Salt Stress-Responsive Isocitrate Lyase Gene,
2018
Faculty of Science
Transcriptome Of Rice Oryza Sativa L. Over-Expressing Oscam1-1 Gene And Characterization Of Salt Stress-Responsive Isocitrate Lyase Gene, Worawat Yuenyong
Chulalongkorn University Theses and Dissertations (Chula ETD)
The previous study of OsCam1-1 showed that the transgenic KDML105 rice over-expressing OsCam1-1 was more tolerant to salt stress than the wild type, so to investigate the role of calmodulin encoded by OsCam1-1 in the salt-responsive mechanism, the transcriptome approach using RNA-seq technique was applied. Transcriptome profile of the transgenic KDML105 rice over-expressing OsCam1-1 under 4 hr of salt stresss (150 mM NaCl) revealed that several cell processes were affected; signaling, hormone-mediated regulation, transcription, secondary metabolism, stress responses, lipid metabolism, glycolysis, TCA cycle, glyoxylate cycle, photosynthesis, and carbohydrate metabolism. Photosynthesis rate and stomatal conductance at day 3 and 5 of …
Functional Characterization Of Inhibitor Of Kappa B Kinase In Black Tiger Shrimp Penaeus Monodon Antiviral Signaling Pathway,
2018
Faculty of Science
Functional Characterization Of Inhibitor Of Kappa B Kinase In Black Tiger Shrimp Penaeus Monodon Antiviral Signaling Pathway, Zittipong Nhnhkorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
The IKK-NF-κB signaling cascade is one of the crucial responsive mechanisms in inflammatory and immune responses. The key kinase proteins called inhibitor of kappa B kinases (IKKs) serve as the core elements involved in cascade activation. Here, the complete open reading frames of IKK homologs including PmIKKβ, PmIKKε1 and PmIKKε2, from the black tiger shrimp Penaeus monodon were identified and characterized for their functions in shrimp antiviral responses. The PmIKK transcripts were widely expressed in various examined tissues and the PmIKKε protein was detected in all three types of shrimp hemocytes. Only the PmIKKε1 and PmIKKε2 were responsive to white …
The Effect Of Nac And Carnosine On AlzheimerS Disease-Related In Vitro Model Through Rage-Age Signaling Pathway,
2018
Faculty of Allied Health Sciences
The Effect Of Nac And Carnosine On AlzheimerS Disease-Related In Vitro Model Through Rage-Age Signaling Pathway, Suphasarang Sirirattanakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Alzheimer’s disease (AD) is the most common dementia which found increasing with age. It involves neurodegeneration which leads to various abnormalities especially memory loss, inability to learn new things, lack of creativity, lack of decision making ability, lack of critical thinking, calculation inability, inability to live normal daily life, inability to recognize person, time and place, emotional disturbance, and difficulty to use language. Since AD has severe impact in various aspects on both the patients and their families, so we are interested to study the neurodegenerative mechanism when neuronal cells are under oxidative stress which will induce neuroinflammation through the …
Study Of Hiv-1 Reverse Transcriptase And Protease Inhibition By Mushroom Extracts,
2018
Faculty of Allied Health Sciences
Study Of Hiv-1 Reverse Transcriptase And Protease Inhibition By Mushroom Extracts, Chanin Sillapachaiyaporn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Human immunodeficiency virus type-1 (HIV-1) can cause acquired immunodeficiency syndrome (AIDS), a world serious public health problem. HIV-1 protease (HIV-1 PR) and reverse transcriptase (HIV-1 RT) are necessary target enzymes which have been used for antiretroviral drugs development. Herein, Lignosus rhinocerus (LR), Auricularia polytricha (AP) and Astraeus spp. (AH) crude extracts were screened for inhibitory activities on both enzymes. Crude hexane extract of AP (APH) exhibited significant inhibition on both HIV-1 PR and RT activities not only in an in vitro non-cell based but also cell based assays. In HIV-1 infected MOLT-4 cell model, APH significantly reduced capsid protein (p24) …
การพัฒนาแบบจำลองเซลล์ลำไส้ของมนุษย์บนกระดาษที่มีการดัดแปรพื้นผิวและต้นแบบไบโอเซนเซอร์ไร้สายสำหรับตรวจวัดการเจริญของจุลชีพก่อโรค,
2018
คณะสหเวชศาสตร์
การพัฒนาแบบจำลองเซลล์ลำไส้ของมนุษย์บนกระดาษที่มีการดัดแปรพื้นผิวและต้นแบบไบโอเซนเซอร์ไร้สายสำหรับตรวจวัดการเจริญของจุลชีพก่อโรค, ปัณณวิชญ์ ถิรบวรกิจพิธาน
Chulalongkorn University Theses and Dissertations (Chula ETD)
วิทยานิพนธ์นี้เป็นการนำเสนองานวิจัย การพัฒนาวิธีการใหม่เพื่อควบคุมและเฝ้าระวังโรคติดเชื้อ โดยประกอบด้วยเนื้อหาสำคัญสองส่วน ได้แก่ (i) การพัฒนาแบบจำลองเซลล์ลำไส้ของมนุษย์ที่เพาะเลี้ยงบนกระดาษที่มีการดัดแปรพื้นผิว เพื่อใช้ประโยชน์ในการศึกษากลไกการบุกรุกของเชื้อจุลชีพก่อโรคในระบบทางเดินอาหาร และ (ii) การพัฒนาต้นแบบไบโอเซนเซอร์แบบไร้สายเพื่อการตรวจติดตามการเจริญของเชื้อจุลชีพก่อโรค โดยในส่วนแรก เซลล์ลำไส้ของมนุษย์ HT-29 จำนวน 200,000 เซลล์ ถูกเพาะเลี้ยงในบริเวณชอบน้ำของกระดาษกรอง Whatman No.1 โดยกระดาษถูกดัดแปรพื้นผิวด้วยสารแมทริกซ์นอกเซลล์ (Extracellular matrix: ECM) ชนิดต่าง ๆ ได้แก่ Matrigel, Collagen-1 และ Laminin พื้นที่เพาะเลี้ยงเซลล์มีขนาด 12.56 ตารางมิลลิเมตร ภายใต้สภาวะที่เหมาะสม เซลล์ HT-29 ที่ถูกเพาะเลี้ยงบนกระดาษ มีชีวิตรอดได้ถึง 28 วัน และแสดงลักษณะของเซลล์ที่เจริญเต็มที่ โดยมีการแสดงออกของวิลไล (villi) ที่ผิวเซลล์ด้านบน (apical) และมีการแสดงออกของโปรตีน ZO-1 ซึ่งแสดงถึงเซลล์มีการสร้างไทต์จังก์ชันเกิดขึ้น จากการใช้สารเชื่อมพันธะสำหรับเชื่อมพันธะ ECM แต่ละชนิด พบว่าเมื่อใช้สารเจนิพินในการเชื่อมพันธะ เซลล์มีชีวิตรอดทั้งหมด (100 -112.8%) ในขณะที่มีเพียง 1.1 - 67.3 % ของเซลล์รอดชีวิต หากใช้สารกลูตารัลดีไฮด์ในการเชื่อมพันธะ แต่การใช้สารเชื่อมพันธะทั้งสองชนิด ทำให้เซลล์ไม่สามารถแบ่งตัวมีรูปร่างแบบสามมิติได้ เมื่อสังเกตด้วย SEM เซลล์มีลักษณะแบน การดัดแปรพื้นผิวกระดาษด้วยสาร ECM ชนิด Matrigel ส่งผลให้เซลล์มีชีวิตรอดมากที่สุดและสาร ECM ชนิด Laminin ทำให้เซลล์เกิดการแปรสภาพ (cell differentiation) ได้ดีที่สุด งานวิจัยส่วนที่ 2 เป็นการพัฒนาไบโอเซนเซอร์ไร้สายสำหรับติดตามการเจริญของเชื้อจุลชีพก่อโรค ได้แก่ เชื้อ Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus gordonii และ Candida albicans พบว่าเชื้อดังกล่าวสามารถสร้างไบโอฟิล์มบนผิวของขั้วไฟฟ้าคาร์บอนอสัณฐาน (glassy carbon electrode) และสามารถให้ค่าศักย์ไฟฟ้าที่เป็นลบได้ …
Influence Of The Estrous Cycle And Female Sex Hormones On Ghb Toxicokinetics,
2018
University of the Pacific
Influence Of The Estrous Cycle And Female Sex Hormones On Ghb Toxicokinetics, Hao Wei
University of the Pacific Theses and Dissertations
Gamma-Hydroxybutyrate (GHB) is an endogenous short-chain fatty acid formed from Gamma-aminobutyric acid (GABA). Clinically, GHB is marketed in the United States as Xyrem to treat narcolepsy with cataplexy and in Europe for the treatment of alcohol withdrawal and narcolepsy. However, the illicit use and abuse of GHB occurs due to its sedative/hypnotic and euphoric effects. Monocarboxylate transporters (MCTs and SMCTs) are integral membrane proteins that control the bidirectional transport of endogenous substrates including lactate, acetate and pyruvate. They have also been found to transport and mediate the clearance and distribution of GHB. MCTs demonstrate a wide tissue distribution, including brain, …
In Vitro Genetic Code Expansion And Selected Applications,
2018
Virginia Commonwealth University
In Vitro Genetic Code Expansion And Selected Applications, Emil S. Iqbal
Theses and Dissertations
The ability of incorporation non-canonical amino acids (ncAAs) using translation offers researchers the ability of extend the functionality of proteins and peptides for many applications including synthetic biology, biophysical and structural studies, and discovery of novel ligands. Here we describe the three projects where the addition of ncAAs to in vitro translation systems creates useful chemical biology techniques. In the first, a fluorinated histidine derivative is used to create a novel affinity tag that allows for the selective purification of peptides from a complex mixture of proteins. In the second, the high promiscuity of an editing-deficient valine-tRNA synthetase (ValRS T222P) …
The Interaction Between Ceramide-1-Phosphate And Group Iva Cytosolic Phospholipase A2 And Its Role In Wound Healing,
2018
Virginia Commonwealth University
The Interaction Between Ceramide-1-Phosphate And Group Iva Cytosolic Phospholipase A2 And Its Role In Wound Healing, Patrick Macknight
Theses and Dissertations
The sphingolipid, ceramide-1-phosphate (C1P), directly binds and activates Group IVA cytosolic phospholipase A2 (cPLA2a) to generate eicosanoids. Due to the role of eicosanoids in wound healing, we choose to use our novel genetic mouse model expressing cPLA2a with an ablated C1P interaction site (KI) to examine the cPLA2a/C1P interaction in wound healing. Wound closure rate was not affected, but wound maturation was dramatically enhanced by loss of the C1P/cPLA2α interaction based on the following findings. Wounds in KI mice displayed: i) increased infiltration of dermal fibroblasts into the wound environment; ii …
Signaling Through Homomeric And Heteromeric Cannabinoid Cb1 Receptors,
2018
Virginia Commonwealth University
Signaling Through Homomeric And Heteromeric Cannabinoid Cb1 Receptors, Guoqing Xiang
Theses and Dissertations
Cannabis (Marijuana) has multiple effects on the human body, such as analgesia, euphoria and memory impairment. Delta-9 tetrahydrocannabinol (D9-THC), the active ingredient in cannabis, binds to cannabinoid receptors, seven-transmembrane G protein-coupled receptors (GPCRs) that mediate a variety of physiological functions. GPCRs were believed to function only in homomeric forms, however, recent findings show that different GPCRs can also form heteromeric complexes that may expand their signaling properties. In this study, we focused on Cannabinoid CB1 receptor (CB1R) heteromers with the mu-opioid receptor (MOR) and the Dopamine type 2 receptor (D2R), respectively. We utilized a variety of techniques, such as the …
Decoding The Signaling Of The D2r-2ar Heteromer: Relevance To Schizophrenia,
2018
Virginia Commonwealth University
Decoding The Signaling Of The D2r-2ar Heteromer: Relevance To Schizophrenia, Miao Huang
Theses and Dissertations
Schizophrenia is a severe mental disorder affecting ~1% of world population. Two G protein coupled receptors (GPCRs): Gi-coupled dopamine D2 receptor (D2R), and Gq-coupled serotonin 2A receptor (2AR), are targeted by the typical and atypical antipsychotic drugs to treat schizophrenia. These two receptors have been shown to co-localize in brain regions relevant to schizophrenia, including the ventral tegmental area (VTA), striatum, and prefrontal cortex (PFC). Studies in our lab characterized the integrated signaling of the D2R-2AR heteromer and found that both the Gi activity of D2R and the Gq activity of 2AR were potentiated …
Nicotinic Acetylcholine Receptor Dependent Effects Of Nicotine On Hek293t And Hbo Cells,
2018
Virginia Commonwealth University
Nicotinic Acetylcholine Receptor Dependent Effects Of Nicotine On Hek293t And Hbo Cells, James D. Larsen
Theses and Dissertations
T2R receptors are the classical bitter taste receptors which detect and transduce bitter taste in a subset of taste receptor cells (TRCs). The TRPM5-dependent T2Rs are G-protein coupled receptors (GPCRs) and are linked to G protein, gustducin to initiate an intracellular signaling cascade for the transduction of bitter tastants. Nicotine is bitter. However, at present the transduction mechanisms for the detection of nicotine in are poorly understood. Previous studies from our laboratory using TRPM5 knockout (KO) mice demonstrated that the T2R pathway is insufficient in explaining the taste perception of nicotine. TRPM5 KO mice elicited chorda tympani (CT) taste nerve …
Processing Of 3′-Blocked Dna Double-Strand Breaks By Tyrosyl-Dna Phosphodiesterase 1, Artemis And Polynucleotide Kinase/ Phosphatase,
2018
Virginia Commonwealth University
Processing Of 3′-Blocked Dna Double-Strand Breaks By Tyrosyl-Dna Phosphodiesterase 1, Artemis And Polynucleotide Kinase/ Phosphatase, Ajinkya S. Kawale
Theses and Dissertations
DNA double-strand breaks (DSBs) containing unligatable termini are potent cytotoxic lesions leading to growth arrest or cell death. The Artemis nuclease and tyrosyl-DNA phosphodiesterase (TDP1) are each capable of resolving protruding 3′-phosphoglycolate (PG) termini of DNA double-strand breaks (DSBs). Consequently, a knockout of Artemis and a knockout/knockdown of TDP1 rendered cells sensitive to the radiomimetic agent neocarzinostatin (NCS), which induces 3′-PG-terminated DSBs. Unexpectedly, however, a knockdown or knockout of TDP1 in Artemis-null cells did not confer any greater sensitivity than either deficiency alone, indicating a strict epistasis between TDP1 and Artemis. Moreover, a deficiency in Artemis, but not TDP1, resulted …
Cellular Inhibitor Of Apoptosis Protein2 – A Critical Regulator Of Neuroinflammation,
2018
Virginia Commonwealth University
Cellular Inhibitor Of Apoptosis Protein2 – A Critical Regulator Of Neuroinflammation, Debolina Dipankar Biswas
Theses and Dissertations
Inhibitors of apoptosis (IAPs) modulate cell death and play critical role in signal transduction that promotes inflammation. Recently, Smac mimetics, which are IAP antagonists, have attracted attention as novel cancer therapeutics. Cellular Inhibitor of Apoptosis 2 (cIAP2), a member of IAP family, positively affects both NF-κB and MAPK activation in response to many inflammatory stimuli. We observed that the lack of cIAP2 ablates LPS-induced neuroinflammation. Also, cIAP2-/- macrophages demonstrated diminished antigen presentation potential that could contribute to ablated immunity. In addition to these functions, we have previously reported that cIAP2 also regulates the activation of Interferon Regulatory Factor 1 …
Chronic Clozapine Treatment Impairs Functional Activation Of Metabotropic Glutamate Receptor 2 Via An Hdac2-Depedent Mechanism,
2018
Virginia Commonwealth University
Chronic Clozapine Treatment Impairs Functional Activation Of Metabotropic Glutamate Receptor 2 Via An Hdac2-Depedent Mechanism, Travis M. Cuddy
Theses and Dissertations
Schizophrenia is a chronic mental disorder affecting millions worldwide. It has no known cure. Current pharmaceutical treatments have shown efficacy in only one of the three symptom clusters of schizophrenia, providing little or no benefit in the other two. Furthermore, the current standard-of-care drugs, known as atypical antipsychotics, carry risks of severe side effects affecting multiple body systems. Most patients opt to discontinue drug therapy within two years of initiation due to lack of efficacy and/or preponderance of adverse effects. Previous findings have shown that chronic usage of atypical antipsychotics causes a 5-HT2A-dependent upregulation of histone deacetylase 2 …
Morphological, Genetic And Biochemical Characterization Of The Anti-Malarial Herb, Artemisia Annua Germplasm Collection At West Virginia University,
2018
West Virginia University
Morphological, Genetic And Biochemical Characterization Of The Anti-Malarial Herb, Artemisia Annua Germplasm Collection At West Virginia University, Delini K. Samarasinghe
Graduate Theses, Dissertations, and Problem Reports (ETD)
Malaria is one of the deadliest diseases in human history. Nearly half of the world’s population, is at the risk in 106 countries. Only in 2016, this disease killed about 445,000 people, 72% of them being children under age five. It also accounts for US $12 billion dollars of direct costs in Africa alone. Five different species of Plasmodium cause malaria but P. falciparum is the most detrimental one, causing 50% of all malaria cases and is considered as the deadliest parasite in humans. Artemisinin (ART), a 15 C sesquiterpenoid is currently the only precursor to the most effective anti-malarial …
The Effects Of Oxidative Stress On P75ntr Signaling In Dopaminergic Neurons,
2018
Eastern Kentucky University
The Effects Of Oxidative Stress On P75ntr Signaling In Dopaminergic Neurons, Cassandra Marie Escobedo
Online Theses and Dissertations
The p75 neurotrophin receptor (p75NTR) is responsible for implementing cellular death during embryonic development and in response to cellular injury. The receptor has been recognized as a contributor of neurodegeneration in numerous pathological conditions. Cleavage of p75NTR by Tumor Necrosis Factor converting enzyme (TACE) and γ-secretase has been observed to be associated with an increase in neurodegeneration. In a previous study, p75NTR was discovered to become activated in sympathetic neurons in response to oxidative stress induced by 4-hydroxynonenal (HNE) in a ligand-independent mechanism. Furthermore, cleavage of the receptor was demonstrated to contribute to the death of sympathetic neurons following oxidative …
Structure Of The Picornavirus Replication Platform: A Potential Drug Target For Inhibiting Virus Replication,
2018
Old Dominion University
Structure Of The Picornavirus Replication Platform: A Potential Drug Target For Inhibiting Virus Replication, Meghan Suzanne Warden
Chemistry & Biochemistry Theses & Dissertations
Picornaviruses are small, positive-stranded RNA viruses, divided into twelve different genera. Members of the Picornaviridae family cause a wide range of human and animal diseases including the common cold, poliomyelitis, foot and mouth disease, and dilated cardiomyopathy. The picornavirus genome is replicated via a highly conserved mechanism involving a presumed cloverleaf structure located at the 5’ noncoding region of the virus genome. The 5’ cloverleaf consists of three stem loops (B, C, and D) and one stem (A), which interact with a variety of virus and host cell proteins during replication. In this dissertation, human rhinovirus serotype 14 (HRV-14) SLB …
Wild-Type P53 Enhances Endothelial Barrier Function By Mediating Rac1 Signalling And Rhoa Inhibition,
2018
Old Dominion University
Wild-Type P53 Enhances Endothelial Barrier Function By Mediating Rac1 Signalling And Rhoa Inhibition, Nektarios Barabutis, Christiana Dimitropoulou, Betsy Gregory, John D. Catravas
Bioelectrics Publications
Inflammation is the major cause of endothelial barrier hyper-permeability, associated with acute lung injury and acute respiratory distress syndrome. This study reports that p53 "orchestrates" the defence of vascular endothelium against LPS, by mediating the opposing actions of Rac1 and RhoA in pulmonary tissues. Human lung microvascular endothelial cells treated with HSP90 inhibitors activated both Rac1- and P21-activated kinase, which is an essential element of vascular barrier function. 17AAG increased the phosphorylation of both LIMK and cofilin, in contrast to LPS which counteracted those effects. Mouse lung microvascular endothelial cells exposed to LPS exhibited decreased expression of phospho-cofilin. 17AAG treatment …
