Humboldt Universität zu Berlin

Department of Microbiology and Immunology, McGill Life Sciences Complex
Montreal, Canada

Head, Section on Molecular Signal Transduction Program for Developmental Neuroscience, NICHD, National Institutes of Health
Bldg 49, Rm 5A22
49 Convent Drive
Bethesda, MD 20892-4480

Séminaire du Département de Biologie Cellulaire et Infection

Summary of research:

Centre For Rheumatology Research - University College London

Institut de Biologie du Développement de Marseille-Luminy, Université Aix-Marseille II, CNRS, UMR 6216, Campus de Luminy case 907,
Marseille cedex 09, France

Publications :
Rauzi M, Verant P, Lecuit T, Lenne PF. Nature and anisotropy of cortical forces orienting Drosophila tissue morphogenesis. Nat Cell Biol. 2008 Dec;10(12):1401-10. Lecuit T, Lenne PF. Cell surface mechanics and the control of cell shape, tissue patterns and morphogenesis. Nat Rev Mol Cell Biol. 2007 Aug;8(8):633-44.

Department of Biological Chemistry
The Weizmann Institute of Science Rehovot, 76100, Israel

Director, Institute of Pharmacology, Medical School of Hannover

Dept. of Molecular Microbiology & Biotechnology, Tel Aviv University, Israel.

SÉMINAIRE DU DÉPARTEMENT GÉNOMES ET GÉNÉTIQUE

Immunology Center - National Heart, Lung and Blood Institute, NIH - Bethesda

The Weizmann Institute of Science
Rehovot, 76100, Israel

Séminaire du Département de Biologie Cellulaire et Infection Co-Invité par le Conseil Pasteur-Weizmann

Summary of research:

Post-translational modifications (PTMs) are ubiquitous in the cell and well acknowledged as a means to regulate the function of proteins and provide a mechanism for increasing the diversity of protein structures. It is often believed that PTMs regulate protein activity by changing the protein surface and introducing new functional groups that act as a signaling tag for binding to other molecules. We propose that PTMs may also control a protein function by modulating the protein biophysical characteristics. PTMs, therefore, can enrich the repertoire of protein characteristics beyond that dictated by their sequence and can be viewed as an economical way to introduce larger diversity to the proteins encoded in the genome. In our research, we focus on the effect of glycosylation [1, 2] and ubiquitination [3] on the biophysical properties of proteins. It is likely that PTMs affect the protein energy landscapes (by affecting the enthalpy or entropy of the folded or the unfolded states) in a way that supports their bioactivity. Using computational and theoretical approaches we show that PTM may modulate the protein characteristics such as thermodynamic stability, kinetics, local dynamics, and structure and some of these new characteristics are likely to be coupled with the function associated with that particular PTM. Understanding the cross-talks between the protein and the conjugates at the molecular level may assist in tailoring the biophysical properties of proteins in general and modulating their cellular function.

Publications:
1. Dalit Shental-Bechor and Yaakov Levy, “The effect of glycosylation on protein folding: A close look at thermodynamic stabilization” Proc. Natl. Acad. Sci. USA., 105, 8526-8261, (2008).

2. Dalit Shental and Yaakov Levy, Folding of glycoproteins: toward understanding the biophysics of the glycosylation code, Current Opinion Structural Biology, 19, 524-533, (2009).

The Weizmann Institute of Science
Rehovot, 76100,
Israël

Nosocomial or hospital-acquired infections are increasingly recognized as a major threat in the complex environment of modern hospitals. In spite of efforts aimed at rationalizing the construction of care-delivery structures, implementing demanding hygiene standards among medical personnel, and achieving controlled use of antibiotics, a significant percentage of hospitalized patients still remain concerned by nosocomial infections. Due to the frequent severity of the cases, these infections collectively represent a huge burden on the health system. The complexity of hospital infrastructures, in particular the air and water delivery systems, the invasive medical and surgical procedures, the increasing number of immunosuppressed patients and the aging of the populations are just some of the factors that contribute to the infectious risk in hospitals.

The 8th Louis Pasteur Conference (CLP8) will overview the major features of nosocomial infections, such as the mechanisms of microbial transmission, the establishment of infections, the antibiotic resistance capacities of microbe communities, the unbalance between pathogenic and commensal microorganisms upon immunosuppression, and the occurrence of infectious catastrophes such as septic shock. The goal of the Conference is to integrate, in a multidisciplinary approach, the most recent epidemiological concepts with up to date molecular and cellular analysis of the pathogenesis of nosocomial microbes.