Recursos de colección

ETD at Indian Institute of Science (3.354 recursos)

Repository of Theses and Dissertations of Indian Institute of Science, Bangalore, India. The repository has been developed to capture, disseminate and preserve research theses of Indian Institute of Science.

Biochemistry (biochem)

Mostrando recursos 1 - 20 de 97

  1. Adjunct Therapy with Curcumin for the Treatment of Malaria : Studies in a Murine Model

    Dende, Chaitanya
    Malaria accounts for 198 million cases worldwide; with a high mortality rate. 584000 deaths were reported in 2013. Malaria is a re-emerging disease globally due to drug resistance, parasite recrudescence and non-availability of a vaccine. Chloroquine, quinine and antifolates served as frontline antimalarial drugs for decades. Development of resistance to chloroquine and antifolates, and the decreased efficacy of mefloquine, and even quinine, in malaria-endemic regions, has led to artemisinin derivatives evolving as frontline drugs. Artemisinin is a potent antimalarial compound and clears around 104 parasites per cycle. Despite being a potent antimalarial, artemisinin derivatives suffer from poor pharmacokinetic properties and...

  2. Structure Elucidation and Biological Evaluation of a Novel Steroidal Saponin, Cholestanol Glucoside Isolated from Saraca Asoca Enodophytic Fuungus, Lasiodiplodia Theobromae

    Valayil, Jinu Mathew
    Although the molecular mechanisms underlying the onset and progression of cancer has been unraveled to a great extend, cancer continues to remain a leading cause of death around the world. Clinical efficacy of the existing anticancer drugs are largely compromised by the inherent and acquired resistance of cancer cell types and the severe side effects evoked by chemotherapeutic agents. Hence, the search for novel anticancer drugs with minimum side effects remains an active area of cancer research. Although molecular targeted drugs are preferred over the conventional cytotoxic chemotherapy, the screening of natural compounds with cytotoxic potentialities continues as they can serve...

  3. Role of Mycobacterium Tuberculosis RecG Helicase in DNA Repair, Recombination and in Remodelling of Stalled Replication Forks

    Thakur, Roshan Singh
    Tuberculosis, caused by the infection with Mycobacterium tuberculosis remained as a major global health challenge with one third of world population being infected by this pathogen. M. tuberculosis can persist for decades in infected individuals in the latent state as an asymptomatic disease and can emerge to cause active disease at a later stage. Thus, pathways and the mechanisms that are involved in the maintenance of genome integrity appear to be important for M. tuberculosis survival, persistence and pathogenesis. Helicases are ubiquitous enzymes known to play a key role in DNA replication, repair and recombination. However, role of helicases in...

  4. Structural and Biochemical Analysis of DNA Processing Protein A (DprA) from Helicobacter Pylori

    Dwivedi, Gajendradhar R
    H. pylori has a panmictic population structure due to high genetic diversity. The homoplasy index for H. pylori is 0.85 (where 0 represents a completely clonal organism and 1.0 indicates a freely recombining organism) which is much higher than homoplasy index for E. coli (0.26) or naturally competent Neisseria meningitides (0.34). It undergoes both inter as well as intra strain transformation. Intergenomic recombination is subject to strain specific restriction in H. pylori. Hence, a high homoplasy index means that competence predominates over restriction in H. pylori. Annotation of the genomes of H. pylori strains 26695 and J99 show the presence of nearly two...

  5. Understanding the Dynamic Organization of the Presequence-Translocase in Translocation of Preproteins Across Mitochondrial Inner Membrane

    Pareek, Gautam
    Mitochondrion is an endosymbiotic organelle synthesizing ~1% of its proteome, while remaining ~99% of the proteins are encoded by the nuclear genome and translated on the cytosolic ribosome. Therefore active mitochondrial biogenesis requires efficient protein transport destined for the different sub-compartments. Mitochondrion contains specialized translocation machineries in the outer and in the inner membrane known as TOM40 and TIM23-complex respectively. Import of a majority of mitochondrial proteome is mediated by inner membrane presequence translocase (TIM23 complex). However, the structural organization of Tim23-complex and mechanisms of mitochondrial inner membrane protein translocation is still elusive. Therefore, the present thesis addresses above elusive...

  6. Infection of Human Cell Lines by Japanese Encephalitis Virus : Increased Expression and Release of HLA-E, a Non-classical HLA Molecule

    Shwetank, *
    Japanese encephalitis virus (JEV) causes viral encephalitis in new born and young adults that is prevalent in different parts of India and other parts of South East Asia with an estimated 6000 deaths per year. JEV is a single stranded RNA virus that belongs to the Flavivirusgenus of the family Flaviviridae. It is a neurotropic virus which infects the central nervous system (CNS). The virus follows a zoonotic life-cycle involving mosquitoes and vertebrates, chiefly pigs and ardeid birds, as amplifying hosts. Humans are dead end hosts. After entry into the host following a mosquito bite, JEV infection leads to acute...

  7. Unraveling the Intricate Architecture of Human Mitochondrial Presequence Translocase - Insights on its Evolution and Role in Tumourigenesis

    Sinha, Devanjan
    The present thesis focuses on the elucidation of human mitochondrial inner membrane presequence-translocation machinery with implications on cancer cell proliferation. Mitochondria are the endosymbiotic organelles in an eukaryotic cell performing a vast repertoire of functions and require approximately 1500 proteins. However, the mitochondria genome contains only 13 protein-coding genes primarily transcribing the complexes of the electron transport chain. Therefore, it is evident that most of the mitochondrial proteome is encoded by the nucleus and synthesized on cytosolic ribosomes. Chapter 1: Mechanism of mitochondrial inner membrane protein translocation and its oncogenic connection. Mitochondria consist of different routes of directing proteins to...

  8. Studies on Novel Functional Responses of Mouse Peritoneal Macrophages to Interferon-gamma : Roles of Nitric Oxide Synthase 2

    Chandrasekar, Bhagawat S
    Interferons are known cytokines that display antiviral, anti-proliferative and immuno-modulatory functions in the host. Interferon-gamma (Ifnγ) is the only type II family interferon that binds to the heterodimeric receptor consisting of two subunits, IfnγR1 and IfnγR2. This specific interaction between Ifnγ and its receptor triggers the activation of Janus Kinase (Jak) – Signal Transducer and Activator of Transcription (Stat) pathway. This triggers a cascade of events leading to modulation of a wide variety of genes resulting in a plethora of responses including antimicrobial activities, induction of Major Histocompatibility Complex encoded molecules etc. The impact of Ifnγ in regulating host defense...

  9. Implications of Soluble Diacylglycerol Acyltransferases in Triacylglycerol Biosynthesis in Yeast and Plants

    Sapa, Hima Rani
    Lipids are stored in a cell for providing energy. The main advantages of storing lipids over carbohydrates like glycogen is that, lipids yield more energy after oxidation because they represent the highly reduced form of carbon, needs less space and water for storage. Conservation of chemical energy in the form of biologically inert form is by storing molecules like triacylglycerol (TAG) and Steryl esters (SE). Triacylglycerol is the major storage form of energy in all eukaryotic cells. During the periods of nutritional excess and nutritional stress, all organisms like bacteria, yeast, animals, and plants can able to do the critical...

  10. DNA Double-Strand Break Repair : Molecular Characterization of Classical and Alternative Nonhomologous End Joining in Mitochondrial and Cell-free Extracts

    Kumar, Tadi Satish
    Maintenance of genomic integrity and stability is of prime importance for the survival of an organism. Upon exposure to different damaging agents, DNA acquires various lesions such as base modifications, single-strand breaks (SSBs), and double-strand breaks (DSBs). Organisms have evolved specific repair pathways in order to efficiently correct such DNA damages. Among various types of DNA damages, DSBs are the most serious when present inside cells. Unrepaired or misrepaired DSBs account for some of the genetic instabilities that lead to secondary chromosomal rearrangements, such as deletions, inversions, and translocations and consequently to cancer predisposition. Nonhomologous DNA end joining (NHEJ) is...

  11. Role of Grp 75 Chaperone Folding Machinery in the Maintenance of Mitochondrial Protien Quality Control

    Goswami, Arvind Vittal
    My research focuses on understanding the importance of human mitochondrial Hsp70 (Grp75) chaperone machinery for the maintenance of protein quality control inside the mitochondrial matrix. The investigations carried out during this study have been addressed towards gaining better insights into the working of Grp75 chaperone folding machinery in association with its diverse set of co-chaperones residing in human mitochondria. Additionally, the research also focuses on explaining the various modes of Grp75 participation leading to multiple disease conditions. The thesis has been divided into the following sections as follows: Chapter I: An introduction to the mitochondrial import machinery and role of...

  12. Identification of the Minimal Domain of RNA Trihosphastase Activity in the L Protien of Rinderpest Virus and Charecterization of its Enzymatic Activities

    Singh, Piyush Kumar
    Morbilliviruses belong to the family Paramyxoviridae of the Mononegavirale order of viruses. The Mononegavirale order contains viruses which contain negatively-polar, non-segmented and single stranded RNA genomes. This order contains some of most lethal pathogens known to the humankind. Ebola virus and Marburg virus are perhaps the most lethal human pathogens. Rinderpest virus, declared eradicated in 2011, was known to be the most significant cattle killer. Similarly the Canine distemper virus and Rabies virus, two topmost canine pathogens belong to this order. The L protein in the viruses of Morbillivirus genus harbours the viral RNA-dependent RNA polymerase that replicates and transcribes...

  13. Functional Characterization of C4 Protien of Cotton Leaf Curl Kokhran Virus - Dabawali

    Guha, Debojit
    1) Geminiviruses are a group of plant viruses which contain circular single stranded DNA molecules as their genomes and the capsid consists of two icosahedra fused together to form twinned or geminate particles. The largest genus in the family Geminiviridae is that of begomoviruses which are of two kinds; the monopartite begomoviruses which contain only one circular single stranded DNA molecule as their genome and the bipartite begomoviruses which contain two circular single stranded DNA molecules (designated DNA-A and DNA-B) as their genomes. In bipartite viruses, the two DNA molecules are enclosed in separate geminate capsids. 2) In bipartite begomoviruses,...

  14. Structure-Function Relationships of Saccharomyces Cerevisiae Meiosis Specific Hop 1 Protein : Implications for Chromosome Condensation, Pairing and Spore Formation

    Khan, Krishnendu
    Meiosis is a specialized type of cell division essential for the production of four normal haploid gametes. In early prophase I of meiosis, the intimate synapsis between homologous chromosomes, and the formation of chiasmata, is facilitated by a proteinaceous structure known as the synaptonemal complex (SC). Ultrastructural analysis of germ cells of a number of organisms has disclosed that SC is a specialized tripartite structure composed of two lateral elements, one on each homolog, and a central element, which, in turn, are linked by transverse elements. Genetic studies have revealed that defects in meiotic chromosome alignment and/or segregation result in...

  15. Mxr1p is a Global Regulator of Multiple Metabolic Pathways in the Methylotrophic Yeast Pichia Pastoris

    Sahu, Umakant
    The present study is aimed at examining the ability of Pichia pastoris to utilize acetate and amino acids as the sole sources of carbon. We demonstrate that the zinc finger transcription factor Mxr1p, which is a positive regulator of methanol metabolism, is also required for the growth of P. pastoris in media containing acetate or amino acids as the sole source of carbon. We have identified the target genes of Mxr1p in cells cultured in media containing acetate or amino acids as the sole carbon source. We conclude that Mxr1p is a global regulator of multiple metabolic pathways in P....

  16. Effect of Heat Exposure On Allogeneic Cytotoxic T Lymphocyte Responses in Mice

    Sukumaran, M K

  17. Understanding the Heat Shock Response Pathway in Plasmodium Falciparum and Identification of a Novel Exported Heat Shock Protein

    Grover, Manish
    Infections or diseases are not just stressful for the one who encounters it. The pathogens causing the same also have to deal with the hostile environment present in the host. The maintenance of physiological homeostatic balance is must for survival of all organisms. This becomes a challenging task for the protozoan parasites which often alternate between two different hosts during their life cycle and thereby encounter several environmental insults which they need to acclimatize against, in order to establish a productive infection. Since their discovery as proteins up-regulated upon heat shock, heat shock proteins have emerged as main mediators of...

  18. Uncovering the Role of Mitochondrial Co-chaperones and Artificial Antioxidants in Cellular Redox Homeostasis

    Srivastava, Shubhi
    The role of mitochondria is multidimensional and ranges in vast areas, including apoptosis, cellular response towards stress, metabolism, which is regulated by a plethora of proteins, acting together to maintain cellular and organellar homeostasis. In spite of the presence of mitochondrial DNA, most of the mitochondrial proteins are nuclear encoded and translocated inside the organelle through dedicated translocases present on outer and inner membrane of mitochondria. To fulfil the cellular energy demand, mitochondria efficiently generate ATP by oxidative phosphorylation, and thus are considered as "power house of cell." There occurs a transfer of electrons from various oxidizable substrates to oxygen,...

  19. Development of an Immunodiagnostic Kit for Species Identification of Snake Bite and Studies on the Cross-Reacting Venom Antigens

    De, Anindya Kanti

  20. Cytosolic Lysophosphatidic Acid Acyltransferase : Implications in Lipid Biosynthesis in Yeast, Plants and Human

    Ghosh, Ananda Kumar
    Cytosolic LPA acyltransferase in yeast An isooctane tolerant strain of S. cerevisiae KK-12 was reported to have increased saturated fatty acid content (Miura et. al., 2000). Amongst the various genes upregulated on isooctane treatment, ICT1 (Increased Copper Tolerance 1) was found to have maximal expression (Miura et. al., 2000; Matsui et. al., 2006). This gene in S. cerevisiae is encoded by YLR099C annotated as Ict1p. However, the physiological significance of Ict1p was not understood. Here we showed that an increase in the synthesis of phosphatidic acid (PA) is responsible for enhanced phospholipid synthesis, which confers organic solvent tolerance to S. cerevisiae. This increase in the PA...

Aviso de cookies: Usamos cookies propias y de terceros para mejorar nuestros servicios, para análisis estadístico y para mostrarle publicidad. Si continua navegando consideramos que acepta su uso en los términos establecidos en la Política de cookies.