22,023 research outputs found
Implication du ppGpp et du régulateur global CodY dans le déclenchement de la compétence chez streptococcus pneumoniae
No full textStreptococcus pneumoniae (le pneumocoque) est une bactérie commensale, présente de façon asymptomatique dans le rhinopharynx de 20 % d'adultes et 50 % d'enfants. Cette bactérie peut devenir un pathogène majeur responsable de pneumonies, de méningites et de septicémies, et cause 1,5 million de morts chaque année dans le monde. Il existe deux méthodes de lutte : l'antibiothérapie et la vaccination. Ces deux stratégies se heurtent à la grande variabilité génétique du pneumocoque, essentiellement due à sa capacité à transformer naturellement. La transformation requiert le développement d'un état physiologique transitoire appelé compétence. Sa régulation met en jeu une boucle autocatalytique conduisant à l'expression des gènes de compétence. Mon travail de thèse a porté sur l'étude des mécanismes moléculaires responsables de l'initiation de la compétence. Des études menées au laboratoire ont montré l'implication indirecte de Ami (transport d'oligopeptides) dans la répression de la compétence. Les acides aminés transportés par Ami pourraient servir de jauge métabolique sentie par RelA (réponse stringente) ou par CodY. Nos résultats montrent que le ppGpp est un activateur de la compétence, mais cette molécule n'est pas le seul signal aboutissant au développement de la compétence, et que CodY pourrait être un répresseur de la compétence. De plus, nous avons montré que codY est essentiel et que son inactivation peut aboutir à la formation de structures mérodiploïdes. De plus, l'absence de CodY peut être compensée par la présence de 2 mutations, fatC et amiC, ou par d'autres mutations qui n'ont pas encore été identifiées.Streptococcus pneumoniae (the pneumococcus) is found in the nasopharynx of 20% of adults and 50% of children. The pneumococcus is a major pathogen, causing pneumonia, otitis media, meningitis and bacteriema. Every year, pneumococcal infections kill 1.5 million people worldwide. The two methods used to fight this pathogen (vaccination and antibiotherapy) can be bypassed by the high genetic variability of the pneumococcus. Natural genetic transformation is responsible for this variability and requires the pneumococcus to enter a transitory physiological state called competence. This state is based on an autocatalytic loop that induces the expression of the genes involved in competence. This thesis focusses on molecular mecanisms that lead to competence initiation in the pneumococcus. Studies carried out in our lab have shown that the Ami transporter is involved in competence regulation. Amino acids (intrenaliszed throught Ami) may be a metabolic gauge for competence regulation. Results show that ppGpp is involved in competence development activation but that other regulatory signals are also involved. The regulator CodY might be a competence repressor. On the other hand, this study has shown that codY is an essential gene and that its inactivation can lead to merodiploid formation. Furthermore, the absence of CodY can be compensated by the presence of two mutations, in the fatC and amiC genes, or by the presence of other mutations not yet characterized
Myosin-cross-reactive antigen (MCRA) protein from Bifidobacterium breve is a FAD-dependent fatty acid hydratase which has a function in stress protection
No full textpeer-reviewedBackground The aim of this study was to determine the catalytic activity and physiological role of myosin-cross-reactive antigen (MCRA) from Bifidobacterium breve NCIMB 702258. MCRA from B. breve NCIMB 702258 was cloned, sequenced and expressed in heterologous hosts (Lactococcus and Corynebacterium) and the recombinant proteins assessed for enzymatic activity against fatty acid substrates. Results MCRA catalysed the conversion of palmitoleic, oleic and linoleic acids to the corresponding 10-hydroxy fatty acids, but shorter chain fatty acids were not used as substrates, while the presence of trans-double bonds and double bonds beyond the position C12 abolished hydratase activity. The hydroxy fatty acids produced were not metabolised further. We also found that heterologous Lactococcus and Corynebacterium expressing MCRA accumulated increasing amounts of 10-HOA and 10-HOE in the culture medium. Furthermore, the heterologous cultures exhibited less sensitivity to heat and solvent stresses compared to corresponding controls. Conclusions MCRA protein in B. breve can be classified as a FAD-containing double bond hydratase, within the carbon-oxygen lyase family, which may be catalysing the first step in conjugated linoleic acid (CLA) production, and this protein has an additional function in bacterial stress protection
Level 1: Ma Grande Famille / My Big Family
No full textTo you young reader we dedicate this book. May he encourage you to read, read and re-read again.
About the Authors:
My name is Cody Barnes. I am nineteen years old. I am a student at Kennesaw State University. I play ultimate frisbee for college.
My name is Moriah Boynton. I am eighteen years old. I am a student at Kennesaw State University too. My main subject at university is psychology.
À toi jeune lecteur nous dédions ce livre. Puisse-t-il t’inciter à lire, lire et relire encore.
À propos des auteurs:
Je m’appelle Cody Barnes. J’ai dix-neuf ans. Je suis étudiant à Kennesaw State University. Je joue au frisbee ultime pour l’université.
Je m’appelle Moriah Boynton. J’ai dix-huit ans. Je suis étudiante à Kennesaw State University aussi. Ma matière principale à l\u27université est la psychologie.https://digitalcommons.kennesaw.edu/globallib/1004/thumbnail.jp
Protecting Animals 36: Author Witi Ihimaera
No full textIn this very special episode of Knowing Animals I am joined by beloved New Zealand author Witi Ihimaera. Witi has written many books featuring nonhuman animals. He offers us a non-colonial lens through which to think about the human/nonhuman relationship
Cody Johnson: capstone
No full text2016 Fall.Colorado State University Art and Art History Department capstone project.Capstone contains the artist's statement, a list of works, and images of works.The artist's statement: The idea of pushing new and innovative concepts to build a lasting impression is more than just an idea to entice a client; it is the foundation for which I create. Over the course of my studies in design, I have been taught to always have a reason behind the design; what message is conveyed with this choice of color? Will this composition convey the ideas I am trying to present? Asking these questions and allowing the work to answer them has been one of the greatest lessons I have learned as an artist. As a designer, my goal is to marry these ideas into work that both captivates and confirms the message it is trying to convey; as an artist, my goal is to take these same ideals and apply them to the way I'd like to see the world. Expose what is ugly, create based on morality, and strive for excellence in all that you do
I Think I Am Philip K. Dick
No full textFor years, noted writer Laurence A. Rickels often found himself compared to novelist Philip K. Dickthough in fact Rickels had never read any of the science fiction writers work. When he finally read his first Philip K. Dick novel, while researching for his recent book The Devil Notebooks , it prompted a prolonged immersion in Dicks writing as well as a recognition of Rickelss own long-documented intellectual pursuits. The result of this engagement is I Think I Am: Philip K. Dick , a profound thought experiment that charts the wide relevance of the pulp sci-fi author and paranoid visionary. I Think I Am: Philip K. Dick explores the science fiction authors meditations on psychic reality and psychosis, Christian mysticism, Eastern religion, and modern spiritualism. Covering all of Dicks science fiction, Rickels corrects the lack of scholarly interest in the legendary Californian author and, ultimately, makes a compelling case for the philosophical and psychoanalytic significance of Philip K. Dicks popular and influential science fiction.Intro -- Contents -- Introjection -- Part I -- Endopsychic Allegories -- Schreber Guardian -- Belief System Surveillance -- Part II -- Deeper Problems -- Veil of Tears -- Go West -- Dick Manfred -- Timing -- Glimmung -- Part III -- Spiritualism Analogy -- Imitating the Dead -- Indexical Layer -- Ilse -- Hammers and Things -- Crucifictions -- Over There -- Martyrology -- Can't Live, Can't Live -- Lola -- Umwelt, Mitwelt, and Eigenwelt -- Outer Race -- The German Introject -- Part IV -- Materialism, Idealism, and Cybernetics -- Startling Stories -- A Couple of Years -- Android Empathy -- Homunculus and Robot -- ALL OF YOU ARE DEAD. I AM ALIVE. -- Go with the Flow -- Part V -- Room for Thought -- Caduceus -- Jump -- Still -- A Wake -- Spätwerk -- Let the Dead Be -- Play Bally -- Das Hund -- Notes -- BibliographyFor years, noted writer Laurence A. Rickels often found himself compared to novelist Philip K. Dickthough in fact Rickels had never read any of the science fiction writers work. When he finally read his first Philip K. Dick novel, while researching for his recent book The Devil Notebooks , it prompted a prolonged immersion in Dicks writing as well as a recognition of Rickelss own long-documented intellectual pursuits. The result of this engagement is I Think I Am: Philip K. Dick , a profound thought experiment that charts the wide relevance of the pulp sci-fi author and paranoid visionary. I Think I Am: Philip K. Dick explores the science fiction authors meditations on psychic reality and psychosis, Christian mysticism, Eastern religion, and modern spiritualism. Covering all of Dicks science fiction, Rickels corrects the lack of scholarly interest in the legendary Californian author and, ultimately, makes a compelling case for the philosophical and psychoanalytic significance of Philip K. Dicks popular and influential science fiction.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
Detail, I am the True Vine from the Laurie Chess-Coumans Memorial Windows
No full textInscription: I AM THE TRUE VINE. Lead Investigator: C. Cody Barteet ([email protected]). Photograph: Katie Oateshttps://ir.lib.uwo.ca/chriswallis_stainedglass_on_arva_stjohnunited/1038/thumbnail.jp
Detail, I am the True Vine from the Laurie Chess-Coumans Memorial Windows, view 2
No full textInscription: I AM THE TRUE VINE. Lead Investigator: C. Cody Barteet ([email protected]). Photograph: Katie Oateshttps://ir.lib.uwo.ca/chriswallis_stainedglass_on_arva_stjohnunited/1039/thumbnail.jp
Replacement of Cakile edentula with Cakile maritima in New South Wales and on Lord Howe Island
No full textTwo species of Cakile (Brassicaceae) have been introduced to Australia and the genus has been a common feature on the beaches of NSW for over 130 years; Cakile edentula has been present for at least 148 years (in NSW since about 1870), while Cakile maritima arrived approximately 114 years ago, (in NSW since about 1969). Collections at CANB and NSW confirm that since around 1970 plants more like Cakile maritima have almost entirely replaced Cakile edentula along the NSW coast. A similar phenomenon is reported for Lord Howe Island
Detail, I am with you always from the Laurie Chess-Coumans Memorial Windows
No full textInscription: I AM WITH YOU ALWAYS. Location: Church Hall. Lead Investigator: C. Cody Barteet ([email protected]). Photograph: Katie Oateshttps://ir.lib.uwo.ca/chriswallis_stainedglass_on_arva_stjohnunited/1040/thumbnail.jp
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