Open Access. Powered by Scholars. Published by Universities.®

Biochemistry Commons

Open Access. Powered by Scholars. Published by Universities.®

2018

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 361 - 390 of 399

Full-Text Articles in Biochemistry

Adenosine Has Two Faces: Regionally Dichotomous Adenosine Tone In A Model Of Epilepsy With Comorbid Sleep Disorders, Ted J. Warren, Timothy A. Simeone, D. David Smith, Ryan Grove, Jiri Adamec, Kaeli K. Samson, Harrison M. Roundtree, Deepak Madhavan, Kristina A. Simeone Jan 2018

Adenosine Has Two Faces: Regionally Dichotomous Adenosine Tone In A Model Of Epilepsy With Comorbid Sleep Disorders, Ted J. Warren, Timothy A. Simeone, D. David Smith, Ryan Grove, Jiri Adamec, Kaeli K. Samson, Harrison M. Roundtree, Deepak Madhavan, Kristina A. Simeone

Department of Biochemistry: Faculty Publications

Objective: Adenosine participates in maintaining the excitatory/inhibitory balance in neuronal circuits. Studies indicate that adenosine levels in the cortex and hippocampus increase and exert sleep pressure in sleep-deprived and control animals, whereas in epilepsy reduced adenosine tone promotes hyperexcitability. To date, the role of adenosine in pathological conditions that result in both seizures and sleep disorders is unknown. Here, we determined adenosine tone in sleep and seizure regulating brain regions of Kv1.1 knockout (KO) mice, a model of temporal epilepsy with comorbid sleep disorders.

Methods: 1) Reverse phase-high performance liquid chromatography (RP-HPLC) was performed on brain tissue to determine levels …


การพัฒนาอุปกรณ์วิเคราะห์ฐานกระดาษสำหรับหาปริมาณสารเพรดนิโซโลนและเดกซาเมทาโซนที่ปลอมปนในผลิตภัณฑ์สมุนไพรด้วยวิธีเคมีไฟฟ้า, วิศรุต พริ้มพราย Jan 2018

การพัฒนาอุปกรณ์วิเคราะห์ฐานกระดาษสำหรับหาปริมาณสารเพรดนิโซโลนและเดกซาเมทาโซนที่ปลอมปนในผลิตภัณฑ์สมุนไพรด้วยวิธีเคมีไฟฟ้า, วิศรุต พริ้มพราย

Chulalongkorn University Theses and Dissertations (Chula ETD)

การปลอมปนของสารสเตียรอยด์ชนิดเดกซาเมทาโซนและเพรดนิโซโลนในผลิตภัณฑ์สมุนไพรเป็นปัญหาสำคัญที่ก่อผลเสียร้ายแรงต่อสุขภาพของผู้ใช้ ในหลาย ๆ ประเทศทั่วโลก โดยเฉพาะอย่างยิ่งในประเทศกำลังพัฒนา งานวิจัยนี้ ประสบความสำเร็จในการพัฒนาอุปกรณ์สำหรับแยกและตรวจวัดปริมาณการปลอมปนของสารสเตียรอยด์ดังกล่าว โดยใช้อุปกรณ์ตรวจวิเคราะห์ฐานกระดาษและใช้หลักการทางเคมีไฟฟ้า (electrochemical paper-based analytical device หรือ ePAD) ซึ่งประกอบด้วยกระดาษ Whatman SG81 ตลับพลาสติกจากการพิมพ์สามมิติ และขั้วไฟฟ้าชนิด screen printed electrode โดยกระดาษ Whatman SG81 ใช้สำหรับแยกสารสเตียรอยด์ชนิดเดกซาเมทาโซนและเพรดนิโซโลน โดยใช้วัฏภาคเคลื่อนที่เป็นสารละลาย 60% ethyl acetate ใน cyclohexane ซึ่งผลการศึกษาพบว่าสามารถแยกสารสเตียรอยด์ดังกล่าวออกจากสิ่งเจือปนต่าง ๆ ได้ภายใน 7 นาที สารสเตียรอยด์ที่แยกออกจากกันบนกระดาษ นำมาวัดปริมาณด้วยเทคนิคเคมีไฟฟ้าชนิด differential pulse voltammetry โดยใช้ตลับพลาสติกจากการพิมพ์สามมิติที่ถูกออกแบบทำให้สารละลายอิเล็กโทรไลต์ถูกขังอยู่บนกระดาษ ทำให้สามารถตรวจวัดสัญญาณทางเคมีไฟฟ้าได้คงที่ ซึ่งอุปกรณ์ที่พัฒนาขึ้นสามารถตรวจวัดปริมาณปลอมปนของสารสเตียรอยด์ทั้งชนิดเดกซาเมทาโซนและ เพรดนิโซโลนได้ในช่วงความเข้มข้นระหว่าง 10 ถึง 500 µg/mL โดยมีค่าสัมประสิทธิ์สหสัมพันธ์เท่ากับ 0.988 และ 0.994 ตามลำดับ มีขีดจำกัดในการตรวจวิเคราะห์เชิงคุณภาพเท่ากับ 3.59 µg/mL และ 6.00 µg/mL ตามลำดับ และขีดจำกัดในการตรวจวิเคราะห์เชิงปริมาณมีค่าเท่ากับ 11.98 µg/mL และ 20.02 µg/mL ตามลำดับ การตรวจวัดปริมาณปลอมปนของสารสเตียรอยด์ทั้งสองชนิดในสิ่งตัวอย่างผลิตภัณฑ์สมุนไพรจริงด้วยวิธีที่พัฒนาขึ้นมีค่าสอดคล้องกับผลที่ตรวจด้วยวิธี HPLC และเป็นวิธีที่ใช้งานง่าย มีต้นทุนต่ำ รวดเร็ว และมีศักยภาพนำไปใช้ตรวจหาสิ่งตัวอย่างผลิตภัณฑ์สมุนไพรที่สงสัยว่ามีการปลอมปนของสารสเตียรอยด์ ในระดับภาคสนาม


New Insights Into The "Manna From Heaven" Hypothesis, Clare Laubenthal Jan 2018

New Insights Into The "Manna From Heaven" Hypothesis, Clare Laubenthal

Honors Program Theses

Titan’s atmosphere is unique in that its atmospheric chemistry is thought to be similar to that of the Earth’s atmosphere during the Archean Era, when bacterial life dominated the Earth1. Tholins form as a result of the radiation of organic gases by ultraviolet light. These molecules are considered alike to the prebiotic hazes that formed in the atmosphere of Earth during the Archean Era and which allowed for the eventual development of microbial life2 . This study investigated whether Earth soil bacteria can grow, using laboratory created tholin analogs, or aerosols, as a nutrient source. This study …


Prebiotic Potential Of Aerosols, Emma Rae Shipley Jan 2018

Prebiotic Potential Of Aerosols, Emma Rae Shipley

Honors Program Theses

A triple quadrupole gas chromatograpy mass spectrometer (GC/MS/QQQ) was used to determine prebiotic molecules of interest in plasma and photochemical aerosols. Glycolic acid was further studied using isotopically doped gases. Plasma and photochemical aerosol analogs were shown to have nucleobases and a few amino acids. Each type of aerosol was also the source of glycolic acid, a precursor to glycine. Using 18O doped CO, it was determined that contamination was not a source of oxygen in the samples. Using different combinations of 13C doped gases in 1:1 combinations of CO and CH4, it was determined that …


Quantitation Without Calibration: Response Profile As An Indicator Of Target Amount, Mrittika Debnath Jan 2018

Quantitation Without Calibration: Response Profile As An Indicator Of Target Amount, Mrittika Debnath

Graduate Research Theses & Dissertations

Quantitative assessment of biomarkers is essential in numerous contexts from decision-making in clinical situations to food quality monitoring to the interpretation of life-science research findings. However, appropriate quantitation techniques are not as widely addressed as detection methods. One of the major challenges in biomarker’s quantitation is the need to have a calibration for correlating a measured signal to a target amount. The step complicates the methodologies and makes them less sustainable. In this work, we addressed the issue via a new strategy: relying on the position of response profile rather than absolute signal for assessment of a target nucleic acid’s …


Quantifying The Differences In Binding Affinity Of Reduced Glutathione For Glutathione S-Transferase At Ph 6.5 And 8.5 Using Isothermal Titration Calorimetry, Clay P. Renshaw Jr., Ronald K. Gary Jan 2018

Quantifying The Differences In Binding Affinity Of Reduced Glutathione For Glutathione S-Transferase At Ph 6.5 And 8.5 Using Isothermal Titration Calorimetry, Clay P. Renshaw Jr., Ronald K. Gary

McNair Poster Presentations

The binding affinity between an enzyme and its substrate is often dependent on the pH of the local environment. Knowing the pH at which reduced glutathione (GSH) binds with the highest affinity to the enzyme glutathione S-transferase (GST) is useful for determining the optimal pH for purification of GST-fusion proteins during GST-affinity chromatography. In this study, GST of the species Schistosoma japonicum was purified, quantified, and utilized to study its binding interaction with GSH at pH 6.5 and 8.5 via isothermal titration calorimetry (ITC). After protein expression, extraction, and purification, the GST concentration was quantified using QubitTM fluorometry. …


Synthesis, Characterisation And Dna Intercalation Studies Of Regioisomers Of Ruthenium (Ii) Polypyridyl Complexes, Laura Perdisatt, Samar Moqadasi, Luke O'Neill, Gary Hessman, Alessandra Ghion, Muhammad Qasim Mushtaq Warraich, Alan Casey, Christine O'Connor Jan 2018

Synthesis, Characterisation And Dna Intercalation Studies Of Regioisomers Of Ruthenium (Ii) Polypyridyl Complexes, Laura Perdisatt, Samar Moqadasi, Luke O'Neill, Gary Hessman, Alessandra Ghion, Muhammad Qasim Mushtaq Warraich, Alan Casey, Christine O'Connor

Articles

Regioisomers of the functional group of the main ligand (L) on a series of [Ru(phen)2L]2+and [Ru(bpy)2L]2+ complexes, where phen is 1,10 phenanthroline and bpy is 2,2′-bipyridine, were synthesised to investigate the interaction with deoxyribonucleic acid (DNA) as potential therapeutics. UV–Vis binding titrations, thermal denaturation and circular dichroism were used to evaluate their interaction with DNA. The conclusions indicated the significance of the auxiliary ligand; especially 1,10-phenanthroline has on the binding constants (Kb). The systematic variation of auxiliary ligand(phen or bpy), and polypyridyl ligand (4-(1H-Imidazo[4,5-f][1,10]phenanthrolin-2-yl)benzonitrile (CPIP), 2-(4-formylphenyl)imidazo[4,5-f] [1,10] phenanthroline (FPIP), 2-(4-bromophenyl)imidazo[4,5-f][1,10]phenanthroline (BPIP) and 2-(4-nitrophenyl)imidazo[4,5-f] [1,10] phenanthroline (NPIP), split in terms of …


Quantitative Genetics Of Populus, Roba Bdeir Jan 2018

Quantitative Genetics Of Populus, Roba Bdeir

Dissertations, Master's Theses and Master's Reports

Evidence for bark, stem and stomatal density adaptation to different climates in the model species Populus is seen in both the natural population as well as in the greenhouse, but the genetic basis of these adaptation remains poorly understood. The present thesis investigates bark texture, bark thickness, diameter and stomatal density variations among Populus population using two quantitative genetics methods to attempt understand the genetic system controlling inheritance of these traits and to associate them with respective genes. The first approach aimed at detecting quantitative trait loci (QTL) associated with all phenotypic traits in an interspecific hybrid pedigree (Populus …


Assembly And Trafficking Of The Cystic Fibrosis Transmembrane Conductance Regulator And Associated Proteins, Zhihui Zhang Jan 2018

Assembly And Trafficking Of The Cystic Fibrosis Transmembrane Conductance Regulator And Associated Proteins, Zhihui Zhang

Theses and Dissertations--Chemistry

Cystic Fibrosis (CF) is an autosomal recessive genetic disease that leads to severe malfunction in many organs, but particularly the lungs. The primary cause of this malfunction is the decrease of the airway surface liquid layer on the lung epithelium. The lack of hydration leads to mucus build up on the epithelial lining, leading to blockage of airways. The underlying cause of CF is the dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR), which results from mutations in the protein. Almost 90% of CF patients are caused by the deletion of the phenylalanine at position 508 of CFTR, which …


Evaluation Of Ispe For Inhibitor Design In The Non-Mevalonate Pathway, Kataryzna Barbara Hoerchler Jan 2018

Evaluation Of Ispe For Inhibitor Design In The Non-Mevalonate Pathway, Kataryzna Barbara Hoerchler

Graduate Research Theses & Dissertations

There is an urgent need to discover new antibiotics to combat the emergence of drug resistant Novel antibiotics that target unique pathways different from existing therapies are promising targets. The non-mevalonate pathway (MEP), which was discovered in the 1990’s, is essential for most bacteria, plants and apicomplexan parasites. Inhibition of the non-mevalonate is an attractive pharmaceutical target, since it is not present in mammals. Many compounds have surfaced as potential inhibitors, but none have made it to market. This thesis investigates the fourth step in the MEP pathway involving the enzyme 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase (IspE) from Escherichia coli (Ec), Burkholderia thailandensis …


Understanding Carbohydrate Recognition Mechanisms In Non-Catalytic Proteins Through Molecular Simulations, Abhishek A. Kognole Jan 2018

Understanding Carbohydrate Recognition Mechanisms In Non-Catalytic Proteins Through Molecular Simulations, Abhishek A. Kognole

Theses and Dissertations--Chemical and Materials Engineering

Non-catalytic protein-carbohydrate interactions are an essential element of various biological events. This dissertation presents the work on understanding carbohydrate recognition mechanisms and their physical significance in two groups of non-catalytic proteins, also called lectins, which play key roles in major applications such as cellulosic biofuel production and drug delivery pathways. A computational approach using molecular modeling, molecular dynamic simulations and free energy calculations was used to study molecular-level protein-carbohydrate and protein-protein interactions. Various microorganisms like bacteria and fungi secret multi-modular enzymes to deconstruct cellulosic biomass into fermentable sugars. The carbohydrate binding modules (CBM) are non-catalytic domains of such enzymes that …


Protein Engineering In The Study Of Protein Labeling And Degradation, Xinyi Zhang Jan 2018

Protein Engineering In The Study Of Protein Labeling And Degradation, Xinyi Zhang

Theses and Dissertations--Chemistry

Proteins are large macromolecules that play important roles in nature. With the development of modern molecular biology techniques, protein engineering has emerged as a useful tool and found many applications in areas ranging from food industry, environmental protection, to medical and life science. Biomimetic membrane incorporates biological elements, such as proteins, to form membranes that mimic the high specificity and conductance of natural biological membranes. For any application involving the usage of proteins, the first barrier is always the production of proteins with sufficient stability, and the incorporation of proteins into the artificial matrix. This thesis contains two major parts, …


Protein Suppression Of Flavin Semiquinone As A Mechanistically Important Control Of Reactivity: A Study Comparing Flavoenzymes Which Differ In Redox Properties, Substrates, And Ability To Bifurcate Electrons, John Patrick Hoben Jan 2018

Protein Suppression Of Flavin Semiquinone As A Mechanistically Important Control Of Reactivity: A Study Comparing Flavoenzymes Which Differ In Redox Properties, Substrates, And Ability To Bifurcate Electrons, John Patrick Hoben

Theses and Dissertations--Chemistry

A growing number of flavoprotein systems have been observed to bifurcate pairs of electrons. Flavin-based electron bifurcation (FBEB) results in products with greater reducing power than that of the reactants with less reducing power. Highly reducing electrons at low reduction midpoint potential are required for life processes of both aerobic and anaerobic metabolic processes. For electron bifurcation to function, the semiquinone (SQ) redox intermediate needs to be destabilized in the protein to suppress its ability to trap electrons. This dissertation examines SQ suppression across a number of flavin systems for the purpose of better understanding the nature of SQ suppression …


Study Of The Mechanism Of Action For Ru(Ii) Polypyridyl Complexes As Potential Anticancer Agents, Yang Sun Jan 2018

Study Of The Mechanism Of Action For Ru(Ii) Polypyridyl Complexes As Potential Anticancer Agents, Yang Sun

Theses and Dissertations--Chemistry

Application of chemotherapeutic agents in current cancer treatment has been limited by adverse effects as poor selectivity results in systemic toxicity; most chemotherapy approaches also experience inherited or acquired drug resistance which lead to reduced treatment outcome. Research efforts have focused on the discovery of novel chemotherapies that overcome the limitations mentioned above. Ru(II) polypyridyl complexes with anti-cancer properties have been extensively studied as traditional cytotoxic agents and photodynamic therapy agents due to their photophysical and photochemical characteristics.

Most research has focused on the design of Ru(II) polypyridyl complexes that have affinities to nucleic acids as inspired by the classic …


Adverse Pregnancy Outcomes And Imbalance In Angiogenic Growth Mediators And Oxidative Stress Biomarkers Is Associated With Advanced Maternal Age Births: A Prospective Cohort Study In Ghana, Enoch Odame Anto, William K. Owiredu, Samuel A. Sakyi, Cornelius A. Turpin, Richard K. Ephraim, Linda A. Fondjo, Christian Obirikorang, Eric Adua, Emmanuel Acheampong Jan 2018

Adverse Pregnancy Outcomes And Imbalance In Angiogenic Growth Mediators And Oxidative Stress Biomarkers Is Associated With Advanced Maternal Age Births: A Prospective Cohort Study In Ghana, Enoch Odame Anto, William K. Owiredu, Samuel A. Sakyi, Cornelius A. Turpin, Richard K. Ephraim, Linda A. Fondjo, Christian Obirikorang, Eric Adua, Emmanuel Acheampong

Research outputs 2014 to 2021

Background Advanced maternal age (AMA) has been associated with negative pregnancy outcomes. Oxidative stress (OS) and defective placental dysfunction are contributing factors. This study determined the association between AMA and adverse pregnancy outcomes, OS biomarkers and angiogenic growth mediators (AGMs) in normal pregnancies. Methods This prospective cohort study conducted at the Obstetrics and Gynaecology (O&G) Department of the Komfo Anokye Teaching Hospital (KATH) finally included 175 normal pregnant women comprising, 58 AMA (35–45 years), 55 (30–34 years) and 62 optimal childbearing age (20–29 years). Venous blood samples were collected at 28–32 weeks for soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth …


Bioinformatic Interrogation Of Phosphonate Tailoring Pathways, Monica Papinski Jan 2018

Bioinformatic Interrogation Of Phosphonate Tailoring Pathways, Monica Papinski

Theses and Dissertations (Comprehensive)

Phosphonates represent an underexploited class of natural products despite their tremendous potential for use in medicine and agriculture. Even less characterized are phosphonate-containing macromolecules such as cell wall lipids and glycans, distinguished by a P-C bond known to provide stability towards hydrolysis. Despite some progress made in revealing cell wall phosphonate tailoring (Pnt) pathways, several barriers impede the discovery and characterization of novel phosphonate biosynthetic pathways. Specifically, a large diversity of gene composition and arrangement is evident surrounding key genes established to participate in phosphonate tailoring pathways, which are identified alongside the presence of the ppm gene encoding the P-C …


Initial Functional Characterization Of Bfo 2291 And Bfo 2294 From Tannerella Forsythia; Degraders Of Chondroitin Sulfate A, Rony Eshaque, Rony Eshaque Jan 2018

Initial Functional Characterization Of Bfo 2291 And Bfo 2294 From Tannerella Forsythia; Degraders Of Chondroitin Sulfate A, Rony Eshaque, Rony Eshaque

Theses and Dissertations (Comprehensive)

Periodontitis is characterized by the inflammation of the periodontal tissues in response to bacterial action. The Global Burden of Disease (GBD) 2010 study shows that periodontitis ranks 6thin the global prevalence of oral health conditions and affects 11% of the world population. It is initiated by the formation of biofilms containing different types of bacteria. These biofilms exist as dental plaque and contain three types of bacteria called Tannerella forsythia, Porphyromonasgingivalis, and Treponema denticola. These three types of bacteria are strongly associated with periodontitis and they are termed as the Red complex. The main focus of the …


Crystal Structure Of (2-{[(8-Aminona­Phthalen-1-Yl)Imino]­Meth­Yl}-4,6-Di-Tert-Butyl­Phenolato-Κ3n,N′,O)Bromido­Nickel(Ii), Patrick O’Brien, Matthias Zeller, Wei-Tsung Less Jan 2018

Crystal Structure Of (2-{[(8-Aminona­Phthalen-1-Yl)Imino]­Meth­Yl}-4,6-Di-Tert-Butyl­Phenolato-Κ3n,N′,O)Bromido­Nickel(Ii), Patrick O’Brien, Matthias Zeller, Wei-Tsung Less

Chemistry: Faculty Publications and Other Works

The title compound, [NiBr(C25H29N2O)], contains an NiII atom with a slightly distorted square-planar coordination environment defined by one O and two N atoms from the 2-{[(8-aminonaphthalen-1-yl)imino]methyl}-4,6-di-tert-butylphenolate ligand and a bromide anion. The Ni—O and Ni—N bond lengths are slightly longer than those observed in the phenyl backbone counterpart, which can be attributed to the larger steric hindrance of the naphthyl group in the structure of the title compound. The molecule as a whole is substantially distorted, with both the planar naphthalene-1,8-diamine and imino–methyl– phenolate substitutents rotated against the NiN2OBr plane by 38.92 (7) and 37.22 (8), respectively, giving the molecule …


Identification Of Genes And Metabolites Involved In Durian Durio Zibethinus Fruit Ripening, Pinnapat Pinsorn Jan 2018

Identification Of Genes And Metabolites Involved In Durian Durio Zibethinus Fruit Ripening, Pinnapat Pinsorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Durian (Durio zibethinus M.), a major economic fruit, actively produces infamous sulfur-containing compounds during ripening. However, sulfur metabolism which is important in this fruit is rarely investigated. In this study, the integration of metabolomics using CE-TOF/MS and transcriptomics using de novo RNA-seq assembly was performed to reveal metabolic changes involved in sulfur metabolism and chemical composition related to fruit quality. During ripening, the expression level of genes involved in sulfur metabolism is concurred with the reduced sulfate ion content in placenta and the up-accumulation of sulfur metabolism-related metabolites in pulps. It is noteworthy that durian pulps highly accumulate γ-glutamylcysteine (γ-EC) …


Development Of Simple Devices For Point-Of-Care Screening Of Bacterial Infection And Inflammatory Markers, Julaluk Noiphung Jan 2018

Development Of Simple Devices For Point-Of-Care Screening Of Bacterial Infection And Inflammatory Markers, Julaluk Noiphung

Chulalongkorn University Theses and Dissertations (Chula ETD)

A paper-based analytical devices (PADs) provides a great benefit in medical diagnostics, especially in the developing world. The first part of this dissertation describes the effect of sample viscosity on PADs for the measurement of pH and nitrite concentration in human saliva. Preliminary study found that viscosity had a significant effect on the calibration curve of nitrite and a consistent curve could be generated after added washing buffer. Nitrite measurement in artificial saliva with viscosity 1.87-5.10 mPa-s was tested on the proposed device and also showed a good correlation with the standard spectrophotometry method (p=0.8484, paired sample t-test, n=20). Moreover, …


Polyamine Accumulation And Responses Of Mango Fruit To Postharvest Polyamine Application, Bussarin Wonnabussapawich Jan 2018

Polyamine Accumulation And Responses Of Mango Fruit To Postharvest Polyamine Application, Bussarin Wonnabussapawich

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mango (Mangifera indicia L.) is a popular tropical fruit which has a great value in both domestic and international markets. Mango is a climacteric fruit which ethylene production increases dramatically, thus leading to a quick ripening process and a short postharvest life. Polyamines (PAs) have been reported to be involved in fruit ripening. Changes in endogenous free polyamines accumulation were measured in two mango cultivars; ‘Nam Dok Mai No.4’ and ‘Nam Dok Mai Si Tong’. Mangoes were allowed to ripen at 25±1 ºC after harvest. It was found that ‘Nam Dok Mai No.4’ mango exhibited higher ethylene production, respiration rate, …


Functional Characterization Of Heat Shock Proteins During Stress Response In Pacific White Shrimp Penaeus Vannamei And Brine Shrimp Artemia Franciscana, Wisarut Junprung Jan 2018

Functional Characterization Of Heat Shock Proteins During Stress Response In Pacific White Shrimp Penaeus Vannamei And Brine Shrimp Artemia Franciscana, Wisarut Junprung

Chulalongkorn University Theses and Dissertations (Chula ETD)

Acute hepatopancreatic necrosis disease (AHPND) caused by the bacterium Vibrio parahaemolyticus carrying toxin produced plasmid (VPAHPND), has led to severe mortalities in farmed penaeid shrimp throughout Asia. Our studies demonstrated that a chronic non-lethal heat shock (chronic-NLHS) could enhance resistance of the Pacific white shrimp Penaeus vannamei to VPAHPND infection. Shrimp exposed to chronic-NLHS (28 °C to 38 °C, 5 min for 7 days) had higher survival rate (>50%) than that of the control non-heated shrimp (20%) when they were challenged with VPAHPND. The qRT-PCR analysis revealed that the expression of heat shock proteins, LvHSP70 and LvHSP90, as well …


Production And Purification Of Mannan Oligosaccharide And Its Role In Tight Junction Assembly In Epithelial Cells, Chatchai Nopvichai Jan 2018

Production And Purification Of Mannan Oligosaccharide And Its Role In Tight Junction Assembly In Epithelial Cells, Chatchai Nopvichai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mannan Oligosaccharide (MOS) is well-known as prebiotic supplement that help increasing life quality of livestocks and animals. Many reports revealed that MOS supplement can help improve intestinal morphology, enhancing growth performance, raising body weight, and increasing metabolic and stress response. MOS feeding also affected several biological processes in peripheral blood mononuclear cells in pigs and modulates expression of many immune-related genes that helps to prevent and reduce the severity of viral infection. However, the mechanism of action of MOS is remained unclear and the production, purification, identification of bioactive MOS molecular type is needed. In this study, we developed a …


Drug Resistance Mechanism Of Ns3/4a Protease And Identification Of Potent Compounds Inhibiting Reverse Transcriptase Of Hepatitis Virus, Jirayu Kammarabutr Jan 2018

Drug Resistance Mechanism Of Ns3/4a Protease And Identification Of Potent Compounds Inhibiting Reverse Transcriptase Of Hepatitis Virus, Jirayu Kammarabutr

Chulalongkorn University Theses and Dissertations (Chula ETD)

Viral Hepatitis has become a public health concern which caused 1.34 million deaths in 2015 and 95% of sickness and untimely deaths come from chronic hepatitis B and C virus infections. The epidemic of viral hepatitis B and C affects around 325 million people worldwide and is 10 times more than the global HIV epidemic. Hepatitis C virus (HCV), which is the main cause of hepatitis C, has a high mutation rate due to the lack of proofreading activity of the RNA polymerase enzyme. One of an attractive target for anti-HCV drug design and development is the NS3/4A serine protease. …


Effect Of Feedback-Resistant Arog Overexpression On L-Phenylalanine Production In Escherichia Coli, Maria Ulfah Jan 2018

Effect Of Feedback-Resistant Arog Overexpression On L-Phenylalanine Production In Escherichia Coli, Maria Ulfah

Chulalongkorn University Theses and Dissertations (Chula ETD)

L-Phenylalanine (L-Phe) is one of the most important amino acids in food and pharmaceutical industries. It is widely used as a nutritional supplement and a precursor for the synthesis of food additives. The market of L-Phe has been stimulated by increasing demand for the low-calorie sweetener, aspartame. In Escherichia coli, the key enzyme which catalyzes the first committed step of aromatic amino acid biosynthesis pathway is 3-deoxy-D-arabino-heptulosonate-7- phosphate synthase (DAHP-synthase). The enzyme has 3 isoforms, AroG, AroF and AroH, which are feedback inhibited by L-Phe, L-Tyr and L-Trp, respectively. AroG, encoded by aroG, is the major isoform contributed about 80% …


Functional Characterization Of White Spot Syndrome Virus-Responsive Mir-750 In Black Tiger Shrimp Penaeus Monodon, Nichaphat Kanoksinwuttipong Jan 2018

Functional Characterization Of White Spot Syndrome Virus-Responsive Mir-750 In Black Tiger Shrimp Penaeus Monodon, Nichaphat Kanoksinwuttipong

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the RNA interference (RNAi) process, small RNAs called microRNAs (miRNAs) modulate gene expression post-transcriptionally by acting as guides to direct Argonaute (Ago)-containing RNA-induced silencing complexes (RISCs) to targeted mRNAs. The Penaeus monodon miR-750 was previously reported as the highly upregulated miRNA during white spot syndrome virus (WSSV) infection. In this study, the computational program and 2D gel electrophoresis technique were used to identify miR-750 target genes. Bioinformatic analysis suggested that the predicted target mRNAs of miR-750 were ubiquitin-conjugating enzyme E2 Q1 gene (UbcQ1), Actin1 (Act1) and Sarcoplasmic calcium-binding protein (Scp). Furthermore, the alteration of protein expression in the stomach …


Identification And Functional Characterization Of Genes And Micrornas From Penaeus Vannamei In Response To Pathogens And Heat Stress, Pakpoom Boonchuen Jan 2018

Identification And Functional Characterization Of Genes And Micrornas From Penaeus Vannamei In Response To Pathogens And Heat Stress, Pakpoom Boonchuen

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the present day, high-throughput (HT) sequencing techniques provide in-depth data on how the transcripts are expressed and regulated and in this case shed light on how innate immunity responds to different stimuli. Acute Hepatopancreatic Necrosis Disease (AHPND) caused by Vibrio parahaemolyticusproducing Pir toxin (VPAHPND) is a current severe bacterial disease in shrimp. Suppression subtractive hybridization (SSH) was used to identify differentially expressed genes (DEGs) in hepatopancreas and hemocyte of VPAHPND-challengedPenaeus vannamei. The hemocyaninand Vago5 were found as up-regulated genes in hepatopancreas and hemocyte of VPAHPND-infectedP. vannamei, respectively. Their functions in shrimp immunity against VPAHPNDinfection were then characterized. The native …


Anticancer Activity Of Mansonone G Derivatives Against Human Non-Small Cell Lung Cancer: Computational And Mechanistic Study, Panupong Mahalapbutr Jan 2018

Anticancer Activity Of Mansonone G Derivatives Against Human Non-Small Cell Lung Cancer: Computational And Mechanistic Study, Panupong Mahalapbutr

Chulalongkorn University Theses and Dissertations (Chula ETD)

Epidermal growth factor receptor (EGFR) and DNA topoisomerase II (Topo II) are the key molecular targets for non-small cell lung cancer (NSCLC) due to its major contribution to complex signaling cascades modulating the survival of cancer cells. In the present study, mansonone G (MG), a naturally occurring quinone-containing compound, and its semi-synthetic ether derivatives were subjected to theoretically and experimentally investigate the anticancer effects on EGFR/Topo II-mediated signaling pathways in NSCLC cell lines expressing wild-type EGFR (A549) and mutant EGFR (H1975). In vitro cytotoxicity screening results demonstrated that butoxy MG (MG3) was more susceptible to H1975 mutant cells (IC50 of …


L-Pipecolic Acid Production In Thra Knockout Escherichia Coli, Suttilak Khuanwilai Jan 2018

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, Thassanai Sitthiyotha Jan 2018

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 …