Conférences
- Jean Luis RAMOS (EEZ-CSIC, Grenade, Espagne) le mardi 17
février 2009 à 11 h : « One-component
and two-component regulatory systems promote solvent tolerance and
degradation in Pseudomonas ».
- Patrice LEROUGE (FRE 3090, IFRMP 23, Université de Rouen),
le vendredi 20 février 2009 à 10 h :
« Vers la production dans des plantes transgéniques de
protéines à usage thérapeutique ».
- Ivo GOMPERTS BONECA (Institut Pasteur, Paris), le
vendredi 20 février 2009 à 11 h 30 :
« The role of peptidoglycan in host-microbe interactions
».
Lieu : IBSM (salle de conférences Jacques Senez), Campus
Joseph Aiguier, Bt IM, CNRS, Marseille
- Jean Luis RAMOS (EEZ-CSIC, Grenade, Espagne)
« One-component and two-component regulatory systems promote
solvent tolerance and degradation in Pseudomonas »
Pseudomonas putida DOT-T1E is an extremely solvent- and
drug-resistant bacterium that is able to thrive in the presence of
toluene. Growth on toluene involves the degradation of this
compound via the TOD pathway, whose expression is driven by the
TodS/TodT two-component system. ITC studies have shown that TodS
binds toluene, creating a phosphorylation cascade that ends up with
TodT-P activating transcription from the promoter catabolic gene
operon. Thriving in toluene is energy-consuming and efflux pumps
play a key role in toluene tolerance. Two one-component regulators,
TtgR and TtgV, control the expression of the TtgABC and TtgGHI
efflux pumps. The mechanism of control will be discussed based on
the 3D structure of regulators bound to effectors. These efflux
pumps and regulators respond to antibiotics, dyes and flavonoids in
addition to solvents.
- Patrice LEROUGE (FRE 3090, IFRMP 23, Université de
Rouen)
« Vers la production dans des plantes
transgéniques de protéines à usage
thérapeutique »
Nos travaux portent sur l'étude et l'ingénierie de la
N-glycosylation de protéines thérapeutiques produites
dans des plantes transgéniques. Les différences
fondamentales entre voies de glycosylation humaine et
végétale nous ont contraints à
développer des stratégies d'ingénierie de la
voie de biosynthèse des N-glycannes chez les plantes.
L'objectif de ces stratégies est de permettre la production
de protéines recombinantes compatibles avec une utilisation
en thérapie humaine.
- Ivo GOMPERTS BONECA (Institut Pasteur, Paris)
« The role of peptidoglycan in host-microbe
interactions »
The peptidoglycan (PGN) is an essential, unique and major component
of the bacterial cell wall. The essential nature of PGN has made it
the target of several classes of successful antibiotics such as
ß-lactams and glycopeptides since assembly of this
macromolecule is coordinated with essential processes such as cell
growth, shape and division. PGN synthesis is accomplished
presumably by proteins complexes involving PGN synthetases (or
penicillin-binding proteins) and PGN hydrolases. Hence, bacteria
constantly remodel and shed their PGN layer into their environment.
Released PGN fragments are an excellent trademark of actively
growing bacteria and are exploited by higher eukaryotes to sense
the presence of bacteria. Mammals sense released PGN fragments by
the intracellular innate immune receptors Nod1 and Nod2 to mount an
adequate response to bacteria, particularly on mucosal surfaces. In
fact, Nod2 loss-of-function polymorphisms are a risk factor for
developing chronic inflammatory bow diseases such as Chron's
disease. This presentation will address the role of peptidoglycan
metabolism both in the context of host/pathogens and
host/commensals interactions.