|
Type |
Award Lecture in Division |
Area |
Frontiers in Chemical Biology & Protein Chemistry |
Room No. |
Room C311+C312 |
Time |
FRI 10:15-: |
Code |
BIO-4 |
Subject |
Structural studies on protein complexes from bacteriophage, flagellum, and divisome |
Authors |
Hyung Ho Lee Division of Chemistry, Seoul National University, Korea |
Abstract |
Atomic structure on protein complexes is crucial for understanding its molecular mechanism. In this talk, I will present structural and functional studies on three protein complexes. In the first part, the structural and functional studies on repressor-antirepressor complex from bacteriophage will be discussed. We showed an uncharacterized mechanism of non-canonical DNA binding and induction by a repressor (Rep) from the temperate Salmonella phage SPC32H; this mechanism was revealed using the crystal structures of homotetrameric Rep (92-198) and a hetero-octameric complex between the Rep and its antirepressor (Ant). The canonical method of inactivating a repressor is through the competitive binding of the antirepressor to the operator-binding site of the repressor; however, these studies revealed several non-canonical features. In the second part, the structural and functional studies on the FliD-FliT complex from Salmonella will be discussed. Bacterial flagellar biogenesis is controlled by a negative feedback loop. When FliD was secreted at the late step of flagellar assembly, the FliD-FliT complex disassembled and free FliT bound to the FlhDC complex, a master regulator of flagellar biogenesis, subsequently inhibiting the overall expression of flagellar proteins. In this study, we analyzed the role of the FliD C-terminal domain in pentamer formation and interaction with FliT. In the third part, the structural and functional studies on the component proteins of divisome will be discussed. |
E-mail |
hyungholee@snu.ac.kr |
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