12 décembre 2024: Dr Athanasios Typas
12H30
CMU - AUDITOIRE MÜLLER (A250)
suivi d'un apéritif
Hôtes: Pre Kimberly KLINE & Pre Dominique SOLDATI-FAVRE
iGE3 - Institute of Genetics and Genomics in Geneva &
Département de microbiologie et médecine moléculaire, Faculté de médecine UNIGE
Dr Athanasios TYPAS
Group Leader & Senior Scientist
Head of Molecular Systems Biology Unit,
European Molecular Biology Laboratory (EMBL),
Heidelberg
« Phages counteract bacterial immunity with a myriad of different ways »
The foundations of molecular biology have been established in the mid of the 20th century by studying bacteriophages. Restriction-modification systems and CRISPR, tools that have propelled genetic engineering, are systems that bacteria use to defend against phage attack. Yet, only recently we have started to understand how extensive and diverse are interactions between bacteria and phages. Myriads of bacterial immunity systems are being identified, many being the origins of eukaryotic innate immunity systems. Yet how broad is the phage arsenal in counteracting such defense system, and whether phages possess broad-acting anti-defense systems remain unclear at the moment.
Our work builds on our recent discovery that the enigmatic bacterial retrons, the first prokaryotic elements discovered to encode a reverse transcriptase, serve actually as phage defense systems. First, I will show how a functional metagenomics approach enabled us to discover dozens of small phage proteins that block the toxic activity of a specific retron. Then I will present the first novel phage mechanism that allows for broad counteracting of bacterial innate immunity systems.
Biography
Nassos is a trained biochemist, molecular microbiologist, and systems biologist. He did his undergraduate studies in Chemistry/Biochemistry at the Aristotle University of Thessaloniki, his PhD at the Free University of Berlin with Regine Hengge and his postdoctoral research at University of California at San Francisco with Carol Gross. Since 2011 he has been running his own group at the European Molecular Biology Laboratory (EMBL) at Heidelberg, and since 2024 he is a heading a Unit/Department of Molecular Systems Biology. His lab develops systems-based quantitative approaches and combines it with mechanistic work to study how bacteria interact with the environment, the host and with each other.
9 déc. 2024