DNA phase transitions inside the capsid of a bacterial virus
소속 :
연사 : Dr. Françoise Livolant(Université Paris Sud XI, France)
일시 : 2011-08-25 14:30 ~
장소 : 500동 L305호
일 시 : 2011년 8월 25일, 2:30 PM
장 소 : 500동 L305호
-Abstract-
After introducing the question of DNA condensation and its relevance in biology, we will concentrate on a bacterial virus, the bacteriophage T5. The double stranded DNA bacteriophage genome is densely packed into the capsid until the ejection is triggered in solution upon interaction of the phage with the purified bacterial receptor. We thus handle DNA molecules of various length, each molecule being isolated from the others inside its own container (80nm in diameter). This population of nano-objects let us analyze the behaviour of isolated and confined DNA molecules upon addition of condensing agents, either a multivalent cation (spermine) that diffuses through the capsid or a stressing polymer such as PolyEthylene Glycol (PEG) that does not permeate the capsid. These observations, performed using cryo-electron microscopy to keep unchanged the aqueous and ionic environment of the molecules, let us analyze phase transitions at the molecular scale and raise new questions in physics and biology.
장 소 : 500동 L305호
-Abstract-
After introducing the question of DNA condensation and its relevance in biology, we will concentrate on a bacterial virus, the bacteriophage T5. The double stranded DNA bacteriophage genome is densely packed into the capsid until the ejection is triggered in solution upon interaction of the phage with the purified bacterial receptor. We thus handle DNA molecules of various length, each molecule being isolated from the others inside its own container (80nm in diameter). This population of nano-objects let us analyze the behaviour of isolated and confined DNA molecules upon addition of condensing agents, either a multivalent cation (spermine) that diffuses through the capsid or a stressing polymer such as PolyEthylene Glycol (PEG) that does not permeate the capsid. These observations, performed using cryo-electron microscopy to keep unchanged the aqueous and ionic environment of the molecules, let us analyze phase transitions at the molecular scale and raise new questions in physics and biology.
